Chagas disease, also called American trypanosomiasis, is a potentially life-threatening illness caused by a parasite that is spread by "kissing bugs", mainly in continental Latin America. It can cause serious heart and gastrointestinal problems, and there are approximately 10,000 deaths every year. Learn about the signs and symptoms of Chagas disease.
“Kissing Bug”
Image by CDC/ CDC Connects; Photo credit: James Gathany
What Is
Chagas Bug
Image by CDC
Chagas Bug
Image by CDC
What Is Chagas Disease?
Left and Right: Various species of triatomine bugs, which if infected can transmit T. cruzi. Center: T. cruzi trypomastigote in a thin blood smear stained with Giemsa. Credit: DPDx
Chagas disease is named after the Brazilian physician Carlos Chagas, who discovered the disease in 1909. It is caused by the parasite Trypanosoma cruzi, which is transmitted to animals and people by insect vectors and is found only in the Americas (mainly, in rural areas of Latin America where poverty is widespread). Chagas disease (T. cruzi infection) is also referred to as American trypanosomiasis.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (13)
Chagas Disease
This is a dorsal view of the kissing bug, Triatoma infestans, a vector for Chagas disease, also known as American trypanosomiasis. These blood-sucking bugs are primarily found in Central and South America, and Mexico. Triatomine, sometimes also referred to as reduviid bugs, become infected after biting an animal or person, who is already infected with the parasite.
Image by CDC/ Donated By the World Health Organization, Geneva, Switzerland
Revealing the Neglect: Chagas Disease
Video by Drugs for Neglected Diseases initiative/YouTube
KILLER DISEASES | Treating Chagas
Video by Médecins Sans Frontières/Doctors Without Borders/YouTube
KILLER DISEASES | Chagas in the Future
Video by Médecins Sans Frontières/Doctors Without Borders/YouTube
Imagen en vista dorsal de un individuo adunto de la especie Triatoma infestans. Tomada del Catálogo de triatominos argentinos 2023.
Image by Fuente/Source: Centro Nacional de Diagnóstico e Investigación en Endemoepidemias. Centro de Estudios Parasitológicos y de Vectores (2023). Catálogo de triatominos argentinos. 1era edición. Ciudad Autónoma de Buenos Aires. Administración Nacional de Laboratorios e Institutos de Salud (ANLIS) Dr. C. Malbrán. CeNDIE-Centro Nacional de Diagnóstico e Investigación en Endemoepidemias. ISBN 978-987-48850-1-2 Diseño e ilustraciones, Ruth Paola Oño. Autores: GeoVin (Marti, Gerardo A.; Ceccarelli, Soledad; Balsalobre, Agustín; Cochero, Joaquín; Dibene, Bárbara y Vicente, María Eugenia). CeNDIE (Manteca Acosta, Mariana; Carbajal de la Fuente, Ana Laura; Lobbia, Patricia A.; Remón, Carolina)/Wikimedia
Chagas Disease
CDC/ Donated By the World Health Organization, Geneva, Switzerland
2:17
Revealing the Neglect: Chagas Disease
Drugs for Neglected Diseases initiative/YouTube
3:24
KILLER DISEASES | Treating Chagas
Médecins Sans Frontières/Doctors Without Borders/YouTube
2:28
KILLER DISEASES | Chagas in the Future
Médecins Sans Frontières/Doctors Without Borders/YouTube
Fuente/Source: Centro Nacional de Diagnóstico e Investigación en Endemoepidemias. Centro de Estudios Parasitológicos y de Vectores (2023). Catálogo de triatominos argentinos. 1era edición. Ciudad Autónoma de Buenos Aires. Administración Nacional de Laboratorios e Institutos de Salud (ANLIS) Dr. C. Malbrán. CeNDIE-Centro Nacional de Diagnóstico e Investigación en Endemoepidemias. ISBN 978-987-48850-1-2 Diseño e ilustraciones, Ruth Paola Oño. Autores: GeoVin (Marti, Gerardo A.; Ceccarelli, Soledad; Balsalobre, Agustín; Cochero, Joaquín; Dibene, Bárbara y Vicente, María Eugenia). CeNDIE (Manteca Acosta, Mariana; Carbajal de la Fuente, Ana Laura; Lobbia, Patricia A.; Remón, Carolina)/Wikimedia
Transmission
Trypanosoma cruzi LifeCycle
Image by DPD CDC/Wikimedia
Trypanosoma cruzi LifeCycle
Trypanosomiasis, American [Trypanosoma cruzi]
An infected triatomine insect vector (or “kissing” bug) takes a blood meal and releases trypomastigotes in its feces near the site of the bite wound. Trypomastigotes enter the host through the wound or through intact mucosal membranes, such as the conjunctiva . Common triatomine vector species for trypanosomiasis belong to the genera Triatoma, Rhodinius, and Panstrongylus. Inside the host, the trypomastigotes invade cells, where they differentiate into intracellular amastigotes . The amastigotes multiply by binary fission and differentiate into trypomastigotes, and then are released into the circulation as bloodstream trypomastigotes . Trypomastigotes infect cells from a variety of tissues and transform into intracellular amastigotes in new infection sites. Clinical manifestations can result from this infective cycle. The bloodstream trypomastigotes do not replicate (different from the African trypanosomes). Replication resumes only when the parasites enter another cell or are ingested by another vector. The “kissing” bug becomes infected by feeding on human or animal blood that contains circulating parasites . The ingested trypomastigotes transform into epimastigotes in the vector’s midgut . The parasites multiply and differentiate in the midgut and differentiate into infective metacyclic trypomastigotes in the hindgut .
Trypanosoma cruzi can also be transmitted through blood transfusions, organ transplantation, transplacentally, and in laboratory accidents.
Image by DPD CDC/Wikimedia
Chagas Disease - Epidemiology & Risk Factors
Chagas disease, or American trypanosomiasis, is caused by the parasite Trypanosoma cruzi. Infection is most commonly spread through contact with the poop of an infected triatomine bug (or “kissing bug”), a blood-sucking insect that feeds on humans and animals.
Infection can also occur from:
Mother-to-baby (congenital),
Contaminated blood products (transfusions),
An organ transplanted from an infected donor,
Laboratory accident (rare), or
Contaminated food or drink (rare).
Chagas disease is common in parts of Mexico, Central America, and South America where an estimated 8 million people are infected. The triatomine bug thrives in poor housing conditions (for example, mud walls, thatched roofs), and in countries where the bug is present, people living in rural areas are at greatest risk for getting infected. Efforts by the public health community to prevent transmission of T. cruzi have resulted in a decrease in the number of new T. cruzi infections and, in some areas, have completely stopped transmission of the parasite by triatomine bugs. Many countries where Chagas disease is common have also started screening donated blood for this disease. However, new cases of Chagas disease transmitted through infected organs, or by mother-to-child (congenital) transmission can still occur.
CDC estimates that more than 300,000 persons with Trypanosoma cruzi infection live in the United States. Most people with Chagas disease in the United States were infected in the parts of Latin America where Chagas disease is found. Although there are triatomine bugs in the United States, only a few cases of Chagas disease from contact with the bugs have been documented in this country.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (1)
3 Deadly Diseases You've Probably Never Heard Of
Video by SciShow/YouTube
5:20
3 Deadly Diseases You've Probably Never Heard Of
SciShow/YouTube
Causal Agents
T. cruzi trypomastigotes in peripheral blood smear
Image by CDC/Wikimedia
T. cruzi trypomastigotes in peripheral blood smear
Under a magnification of 1200X, this photomicrograph of a blood sample specimen, revealed the presence of four flagellated, Trypanosoma cruzi parasites, referred to as trypomastigotes. The two parasites at left are considered the large type, while the two at right were of the small type.
Image by CDC/Wikimedia
Chagas Disease - Biology
Causal Agent:
The protozoan parasite, Trypanosoma cruzi, causes Chagas disease, a zoonotic disease that can be transmitted to humans by blood-sucking triatomine bugs.
Life Cycle:
An infected triatomine insect vector (or “kissing bug”) takes a blood meal and releases trypomastigotes in its feces near the site of the bite wound. Trypomastigotes enter the host through the wound or through intact mucosal membranes, such as the conjunctiva (1). Common triatomine vector species for trypanosomiasis belong to the genera Triatoma, Rhodnius, and Panstrongylus. Inside the host, the trypomastigotes invade cells near the site of inoculation, where they differentiate into intracellular amastigotes (2). The amastigotes multiply by binary fission (3) and differentiate into trypomastigotes, and then are released into the circulation as bloodstream trypomastigotes (4). Trypomastigotes infect cells from a variety of tissues and transform into intracellular amastigotes in new infection sites. Clinical manifestations can result from this infective cycle. The bloodstream trypomastigotes do not replicate (different from the African trypanosomes). Replication resumes only when the parasites enter another cell or are ingested by another vector. The “kissing bug” becomes infected by feeding on human or animal blood that contains circulating parasites (5). The ingested trypomastigotes transform into epimastigotes in the vector’s midgut (6). The parasites multiply and differentiate in the midgut (7) and differentiate into infective metacyclic trypomastigotes in the hindgut (8).
Trypanosoma cruzi can also be transmitted through blood transfusions, organ transplantation, transplacentally (from mother to unborn baby), and in laboratory accidents.
Life cycle image and information courtesy of DPDx.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (2)
Disease Vectors
This illustration depicts a dorsal view of the kissing bug, Triatoma rubida. Some of its key morphologic characteristics included: a pale margin around the outer edge of the abdomen, and though not visible here, inferiorly, a longitudinally flattened abdomen; its first antennal segment that reached, or surpassed the tip of its head; its mouthparts bore long hairs at their tips; though not apparent here, an overall coloration that was light reddish brown, to dark brown; a pronotum that was dark with light areas on its sides. T. rubida and other kissing bugs are vectors for Chagas disease, which is transmitted during human contact with the feces of an infected Triatomine sp. vector. Chagas is caused by the parasite Trypanosoma cruzi, and is incurable. Note that the inset described the distribution of Triatoma rubida in the Southwestern United States.
Image by CDC/ Dr. H. Scott
KILLER DISEASES | A History of Chagas
Video by Médecins Sans Frontières/Doctors Without Borders/YouTube
Disease Vectors
CDC/ Dr. H. Scott
2:59
KILLER DISEASES | A History of Chagas
Médecins Sans Frontières/Doctors Without Borders/YouTube
Congenital Chagas Disease
How your Breast adapt to feeding
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How your Breast adapt to feeding
When you breastfeed, your baby’s sucking stimulates nerves in your nipple. These nerves carry a message to your brain, and a hormone, called oxytocin, is released. Oxytocin flows through your bloodstream to your breast, where it causes tiny muscle cells around milk glands to squeeze milk out of the glands into the milk ducts. A well-functioning let-down reflex helps ensure your baby gets milk easily and your breast are emptied. Even if you don’t feel the letdown, you will notice that your baby’s sucking slows down and swallowing increases to keep up with the flow of your milk.
Image by TheVisualMD
Congenital Chagas Disease
In the United States, an estimated 40,000 women of childbearing age are infected with Trypanosoma cruzi, the parasite that causes Chagas disease. The risk of transmission from mother-to-child is thought to be low, with an estimated 1-5% of infants born in the United States to mothers with Chagas disease infected with T. cruzi. This translates to between 63 to 315 infected infants born every year.
Identification and testing of infants at risk of infection is critical to prevent Chagas disease in the United States.
Most babies born with congenital Chagas disease have mild or no signs of illness. However, infection will persist for life and these infants are at risk for developing clinical manifestations of chronic Chagas disease later in life, unless treated.
Infants born with signs of Chagas disease may present with the following:
Low birth weight
Prematurity
Low Apgar scores
Hepatosplenomegaly
Anemia
Thrombocytopenia
Severe disease—such as meningoencephalitis, pneumonitis, or anasarca—and even death can occur in infected infants but is rare.
Women at risk for Chagas disease should be screened for infection before or during pregnancy. Women who have lived in Mexico, Central America, and South America are at greatest risk for Chagas disease.
Although the triatomine insects that transmit Trypanosoma cruzi are present in the southern half of the United States, few cases have been documented as a result of exposure to these insects in the United States and the risk is likely low. Routine testing of pregnant women is not indicated unless there is concern for exposure to triatomines.
For women with Chagas disease, treatment with benznidazole or nifurtimox is typically delayed until after pregnancy and breastfeeding because of concerns about drug safety. Benznidazole is approved by FDA for use in children 2–12 years of age and is commercially available at http://www.benznidazoletablets.com/en/. Nifurtimox is not currently FDA approved and is available under an investigational protocol from CDC.
An infant should be evaluated for congenital Chagas disease if:
The mother has been diagnosed with Chagas disease;
The infant has signs suggestive of Chagas disease; or
The mother has not been screened but is from an endemic area where she may have acquired the infection.
Infant diagnosis relies on detection of the parasite after birth by microscopic examination of blood smears and/or PCR testing for Trypanosoma cruzi DNA in blood. Because the infected mother’s antibody to T. cruzi can persist in her infant for up to 9–12 months, serologic testing is not useful for detecting congenital infection in newborn infants. Over time, the mother’s antibody will disappear and children who are uninfected should be antibody negative by 9–12 months of age.
Treatment is recommended for all cases of congenital Chagas disease. The cure rate is >90% when treatment is given in the first year of infection. Nifurtimox and benznidazole are both effective for treatment of congenital Chagas disease.
Siblings of an infant with congenital Chagas disease should be evaluated for Chagas disease.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (1)
Toxoplasmosis | Acquired vs Congenital | Signs, Symptoms, Diagnosis and Treatment
Video by JJ Medicine/YouTube
10:18
Toxoplasmosis | Acquired vs Congenital | Signs, Symptoms, Diagnosis and Treatment
JJ Medicine/YouTube
Symptoms
Chagas disease
Image by Extracted from the article: "Louis-Alexandre Romaña has granted permission for the reuse of the photographs that he owns and that he has provided (Figs 1 and 3) and for his letter. Written permission is included as Supporting information.Dr. Faustino TORRICO has granted permission for the reuse of the photograph that he owns and that he has provided (Fig 2)."The article has three authors, Beucler N, Torrico F and Hibbert DBeucler N, Torrico F, Hibbert D (2020) A tribute to Cecilio Romaña: Romaña’s sign in Chagas disease. PLoS Negl Trop Dis 14(11): e0008836. https://doi.org/10.1371/journal.pntd.0008836/Wikimedia
Chagas disease
Foto de una niña con signo de Romaña, tomada en los jardines de la Universidad Mayor de San Simón, Bolivia alrededor del año 1980. La imagen fue modificada para mantener el anonimato de la persona fotografiada.
Image by Extracted from the article: "Louis-Alexandre Romaña has granted permission for the reuse of the photographs that he owns and that he has provided (Figs 1 and 3) and for his letter. Written permission is included as Supporting information.Dr. Faustino TORRICO has granted permission for the reuse of the photograph that he owns and that he has provided (Fig 2)."The article has three authors, Beucler N, Torrico F and Hibbert DBeucler N, Torrico F, Hibbert D (2020) A tribute to Cecilio Romaña: Romaña’s sign in Chagas disease. PLoS Negl Trop Dis 14(11): e0008836. https://doi.org/10.1371/journal.pntd.0008836/Wikimedia
Chagas Disease - Disease
Chagas disease has an acute and a chronic phase. If untreated, infection is lifelong.
Acute Chagas disease occurs immediately after infection, and can last up to a few weeks or months. During the acute phase, parasites may be found in the circulating blood. This phase of infection is usually mild or asymptomatic. There may be fever or swelling around the site of inoculation (where the parasite entered into the skin or mucous membrane). Rarely, acute infection may result in severe inflammation of the heart muscle or the brain and lining around the brain.
Following the acute phase, most infected people enter into a prolonged asymptomatic form of disease (called “chronic indeterminate”) during which few or no parasites are found in the blood. During this time, most people are unaware of their infection. Many people may remain asymptomatic for life and never develop Chagas-related symptoms. However, an estimated 20–30% of infected people will develop severe and sometimes life-threatening medical problems over the course of their lives.
Complications of chronic Chagas disease may include
Heart rhythm abnormalities that can cause sudden death;
A dilated heart that doesn’t pump blood well; and
A dilated esophagus or colon, leading to difficulties with eating or passing stool.
In people who have suppressed immune systems (for example, due to AIDS or chemotherapy), Chagas disease can reactivate with parasites found in the circulating blood. Reactivation can potentially cause severe disease.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (3)
Child suffering from Chagas disease
This Panamanian child had been suffering from Chagas disease, which manifested as an acute infection, with swelling of his right eye, otherwise known as Romaña's sign. Chagas Disease is caused by the parasitic protozoan, Trypanosoma cruzi, and is transmitted, when the insect vector from the family, Reduviidae, subfamily Triatominae, is blood-feeding on its human host.
Image by CDC/ Dr. Mae Melvin
Chagas disease
Heart pathology Chagas disease : Large scale anatomy of a heart that has been damaged by chronic Chagas disease
Image by CDC
KILLER DISEASES | How the Body Reacts to Chagas
Video by Médecins Sans Frontières/Doctors Without Borders/YouTube
Child suffering from Chagas disease
CDC/ Dr. Mae Melvin
Chagas disease
CDC
3:21
KILLER DISEASES | How the Body Reacts to Chagas
Médecins Sans Frontières/Doctors Without Borders/YouTube
Diagnosis
Trypanosoma cruzi in a blood smear
Image by Dr Graham Beards/Wikimedia
Trypanosoma cruzi in a blood smear
Trypanosoma cruzi in blood Giemsa stain
Image by Dr Graham Beards/Wikimedia
Chagas Disease - Diagnosis
During the acute phase of infection, parasites may be seen circulating in the blood. The diagnosis of Chagas disease can be made by observation of the parasite in a blood smear by microscopic examination. A thick and thin blood smear are made and stained for visualization of parasites.
Diagnosis of chronic Chagas disease is made after consideration of the patient’s clinical findings, as well as by the likelihood of being infected, such as having lived in a country where Chagas disease is common. Diagnosis is generally made by testing for parasite specific antibodies.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (3)
Blood Smear Showing Normal Red Blood Cell Count
Individual blood cells were first detected and described in the 17th century. Later, red blood cells were counted manually from a blood smear, a thin film of blood prepared on a glass slide and examined under a microscope. Blood analysis is now automated, though blood smears are still used to detect visible abnormalities and to check or confirm the results of other tests. There are normally between 4.2-5.8 million red blood cells per microliter (about a drop), which means there are 20-30 trillion red blood cells circulating through the body of an adult.
Image by TheVisualMD
Chagas Disease - An overview
Video by Let's Learn About Bugs/YouTube
Animal Diseases
This photomicrograph of a bladder tissue sample, revealed the presence of numerous, parasitic, Trypanosoma cruzi protozoa, which had entered the intracellular, amastigote phase of their lifecycle.
A blood smear examines the size, shape, and number of blood cells in a sample of your blood. A blood smear can also detect parasites in your blood. A blood smear may be used to help diagnose and monitor many conditions.
A blood smear examines the size, shape, and number of blood cells in a sample of your blood. A blood smear can also detect parasites in your blood. A blood smear may be used to help diagnose and monitor many conditions.
A blood smear is a sample of blood that's spread on a glass slide which is treated with a special stain. In the past, all blood smears were examined under a microscope by laboratory professionals. Now automated digital systems may be used to help examine blood smears.
The purpose of examining a blood smear is to check the size, shape, and number of three types of blood cells:
Red blood cells, which carry oxygen from your lungs to the rest of your body
A blood smear is used to help diagnose and monitor many conditions, such as blood disorders, sudden kidney failure, and treatment for certain cancers.
You may need a blood smear if you have abnormal results on a complete blood count (CBC). A CBC is a routine test that measures many different parts of your blood.
Your health care provider may order a blood smear if you have symptoms of a blood disorder, such as:
Fatigue
Jaundice, a condition that causes your skin and eyes to turn yellow
Unusual bleeding, including nosebleeds
Fever that lasts, or comes and goes
Bone pain
Anemia
Easy bruising
A spleen that's larger than normal
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
You don't need any special preparation for a blood smear. If your provider has ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test. Your provider will let you know if there are any special instructions to follow.
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
The results of a blood smear alone usually can't diagnose a medical condition. Your provider will use your results combined with your medical history, symptoms, and other test results to make a diagnosis.
Your blood smear results usually describe the appearance and number of your red blood cells, white blood cells, and platelets. Your results will describe anything unusual about your blood.
Red blood cell results that aren't normal, it may be a sign of:
Anemia
Sickle cell anemia
Hemolytic anemia, a type of anemia in which the body destroys red blood cells faster than they are replaced
Thalassemia
Bone marrow disorders
Liver disease
Cancer that has spread to the bone
White blood cell results that aren't normal may be a sign of:
Infection or inflammation
Allergies
Leukemia
Bone marrow disorders
Platelet results that aren't normal may be a sign of:
Thrombocytopenia, a condition in which your blood doesn't have enough platelets, which increases the risk of bleeding
Inherited platelet disorders (uncommon), such as Bernard-Soulier syndrome
If you have been very ill or stressed, or you have had a blood transfusion, the shape and number of your blood cells may be different than usual. So, a blood smear may not provide enough information for your provider to make a diagnosis. If any of your blood smear results are not normal, your provider will likely order more tests. Talk with your provider to learn more about your results.
A blood smear may be used to help find certain types of parasites in your blood which cause diseases, such as:
Malaria, spread by bites from infected mosquitos
Babesiosis, spread mainly by bites from infected ticks
Chagas disease, spread mainly by bites from "kissing bugs" (triatomine)
Your provider may order the test if you live in or travel to areas where you might have been infected, and you have symptoms. Symptoms depend on the type of parasite. Common symptoms may include fever, fatigue, body aches, rash, and problems with digestion.
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Additional Materials (9)
Red Blood Cells, Blood Smear
Individual blood cells were first detected and described in 17th century. Later, red blood cells were counted manually from a blood smear, a thin film of blood prepared on a glass slide and examined under a microscope. Blood analysis is now automated, though blood smears are still used to detect visible abnormalities. There are normally between 4.2-5.8 million red blood cells per microliter (about a drop), which means there are 20-30 trillion red blood cells circulating through the body of an adult.
Image by TheVisualMD
Blood smear (stained and unstained)
Two peripheral blood smears suitable for characterization of cellular elements. Left smear is unstained, right smear is stained with Wright-Giemsa stain.
Image by Coinmac/Wikimedia
Document by Office on Women's Health, U.S. Department of Health and Human Services
How Blood Clots Form
Video by Vascular Cures/YouTube
Platelet Activation and Factors for Clot Formation
Video by Thrombosis Adviser/YouTube
How dangerous are blood clots?
Video by CNN/YouTube
Immune System - Natural Killer Cell
Video by Kyle Thornthwaite/YouTube
Why do blood types matter? - Natalie S. Hodge
Video by TED-Ed/YouTube
Sickle cell anaemia | NHS
Video by NHS/YouTube
Red Blood Cells, Blood Smear
TheVisualMD
Blood smear (stained and unstained)
Coinmac/Wikimedia
Office on Women's Health, U.S. Department of Health and Human Services
3:56
How Blood Clots Form
Vascular Cures/YouTube
2:08
Platelet Activation and Factors for Clot Formation
Thrombosis Adviser/YouTube
1:27
How dangerous are blood clots?
CNN/YouTube
3:02
Immune System - Natural Killer Cell
Kyle Thornthwaite/YouTube
4:42
Why do blood types matter? - Natalie S. Hodge
TED-Ed/YouTube
4:40
Sickle cell anaemia | NHS
NHS/YouTube
White Blood Count (WBC)
White Blood Count (WBC)
Also called: WBC, WBC Blood Test, White Blood Count, White Blood Cell Count, Leukocyte Count, Leukopenia Test, Leukocytosis Test
A white blood count measures the number of white cells in your blood. White blood cells are part of the immune system. A count that is too high or too low can indicate an infection, immune system disorder, or another health problem.
White Blood Count (WBC)
Also called: WBC, WBC Blood Test, White Blood Count, White Blood Cell Count, Leukocyte Count, Leukopenia Test, Leukocytosis Test
A white blood count measures the number of white cells in your blood. White blood cells are part of the immune system. A count that is too high or too low can indicate an infection, immune system disorder, or another health problem.
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Use the slider below to see how your results affect your
health.
WBC/µL
4500
11000
Your result is Normal.
Normally, people produce about 100 billion white blood cells (WBCs) a day. The total white blood cell count normally ranges between 4,500 and 11,000 WBCs per microliter.
Related conditions
A white blood count measures the number of white cells in your blood. White blood cells are part of the immune system. They help your body fight off infections and other diseases.
When you get sick, your body makes more white blood cells to fight the bacteria, viruses, or other foreign substances causing your illness. This increases your white blood count.
Other diseases can cause your body to make fewer white blood cells than you need. This lowers your white blood count. Diseases that can lower your white blood count include some types of cancer and HIV/AIDS, a viral disease that attacks white blood cells. Certain medicines, including chemotherapy, may also lower the number of your white blood cells.
There are five major types of white blood cells:
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
A white blood count measures the total number of these cells in your blood. Another test, called a blood differential, measures the amount of each type of white blood cell.
Other names: WBC count, white cell count, white blood cell count
A white blood count is most often used to help diagnose disorders related to having a high white blood cell count or low white blood cell count.
Disorders related to having a high white blood count include:
Autoimmune and inflammatory diseases, conditions that cause the immune system to attack healthy tissues
Bacterial or viral infections
Cancers such as leukemia and Hodgkin disease
Allergic reactions
Disorders related to having a low white blood count include:
Diseases of the immune system, such as HIV/AIDS
Lymphoma, a cancer of the bone marrow
Diseases of the liver or spleen
A white blood count can show if the number of your white blood cells is too high or too low, but it can't confirm a diagnosis. So it is usually done along with other tests, such as a complete blood count, blood differential, blood smear, and/or bone marrow test.
You may need this test if you have signs of an infection, inflammation, or autoimmune disease. Symptoms of infection include:
Fever
Chills
Body aches
Headache
Symptoms of inflammation and autoimmune diseases will be different, depending on the area of inflammation and type of disease.
You may also need this test if you have a disease that weakens your immune system or are taking medicine that lowers your immune response. If the test shows your white blood count is getting too low, your provider may be able to adjust your treatment.
Your newborn or older child may also be tested as part of a routine screening, or if they have symptoms of a white blood cell disorder.
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out.
To test children, a health care provider will take a sample from the heel (newborns and young babies) or the fingertip (older babies and children). The provider will clean the heel or fingertip with alcohol and poke the site with a small needle. The provider will collect a few drops of blood and put a bandage on the site.
You don't need any special preparations for a white blood count.
After a blood test, you may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
There is very little risk to your baby or child with a needle stick test. Your child may feel a little pinch when the site is poked, and a small bruise may form at the site. This should go away quickly.
A high white blood count may mean you have one of the following conditions:
A bacterial or viral infection
An inflammatory disease such as rheumatoid arthritis
An allergy
Leukemia or Hodgkin disease
Tissue damage from a burn injury or surgery
A low white blood count may mean you have one of the following conditions:
Bone marrow damage. This may be caused by infection, disease, or treatments such as chemotherapy.
Cancers that affect the bone marrow
An autoimmune disorder, such as lupus (or SLE)
HIV/AIDS
If you are already being treated for a white blood cell disorder, your results may show if your treatment is working or whether your condition has improved.
If you have questions about your results, talk to your health care provider.
White blood count results are often compared with results of other blood tests, including a blood differential. A blood differential test shows the amount of each type of white blood cell, such as neutrophils or lymphocytes. Neutrophils mostly target bacterial infections. Lymphocytes mostly target viral infections.
A higher than normal amount of neutrophils is known as neutrophilia.
A lower than normal amount is known as neutropenia.
A higher than normal amount of lymphocytes is known as lymphocytosis.
A lower normal amount is known as lymphopenia.
White Blood Count (WBC): MedlinePlus Medical Test [accessed on Jan 20, 2024]
WBC count: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
White Blood Cell Count (WBC Blood Test) - Testing.com. Sep 28, 2022 [accessed on Jan 20, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (37)
White Blood Cell Count: Bone Marrow
Disease or damage to the bone marrow, caused by infection, cancer, radiation treatment, or chemotherapy can lower white blood cell count by impairing the marrow's ability to produce new white blood cells.
Image by TheVisualMD
White Blood Cells, Bone Marrow
Bone marrow is constantly producing blood cells, including white blood cells and red blood cells as well platelets, which are cell fragments important for blood clotting. Disease and disorders of the bone marrow can, in turn, affect the production of blood cells. Both cancer and cancer treatment (chemotherapy and radiation) can also have an impact on the bone marrow's ability to produce blood cells.
Image by TheVisualMD
This browser does not support the video element.
Complete Blood Count, and Baselining Your Health
Video Topics : Our lifeblood consists of many components and a complete blood count (CBC) includes measurements of the fundamental elements. The largest categories are red and white blood cells (RBCs and WBCs) and cell fragments called platelets, which play roles in blood clotting. There are 20-30 trillion red blood cells in the body of an adult, each with a lifespan of about 100 days (RBCs contain an iron-containing protein called hemoglobin that enables them to carry oxygen to tissues throughout the body and then return carbon dioxide to the lungs). WBCs are in the front lines in the body's ongoing fight against harmful viruses, bacteria and even fungus; when a pathogen enters the body, WBCs mobilize in a coordinated defense response to eliminate, neutralize or mark the invader for destruction. The liquid portion of blood is called plasma and it carries nutrients, electrolytes, waste products, and hormones.
Video by TheVisualMD
The Immune System Explained I – Bacteria Infection
Video by Kurzgesagt – In a Nutshell/YouTube
Immune Response to Bacteria
Video by NIAID/YouTube
Immunology - Adaptive Immune System
Video by Armando Hasudungan/YouTube
Immune System - Natural Killer Cell
Video by Kyle Thornthwaite/YouTube
Your Immune System: Natural Born Killer - Crash Course Biology #32
Video by CrashCourse/YouTube
White Blood Cell and Red Blood Cell
Medical visualization of blood cells. Depicted are numerous red blood cells and a single white blood cell.
Image by TheVisualMD
White Blood Cell and Red Blood Cell
Medical visualization of blood cells. Depicted are numerous red blood cells and a single white blood cell.
Image by TheVisualMD
Red Blood Cell and White Blood Cell
Visualization of red blood cells and a white blood cell
Image by TheVisualMD
Sensitive content
This media may include sensitive content
Blood cells (from left to right: erythrocyte, thrombocyte, leukocyte)
A single drop of blood contains millions of red blood cells, white blood cells, and platelets. One of each type is shown here, isolated from a scanning electron micrograph.
Image by Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)
Bone structure
Anatomy of the bone. The bone is made up of compact bone, spongy bone, and bone marrow. Compact bone makes up the outer layer of the bone. Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Image by Smart Servier website
Blood Cells
Formed Elements of Blood
Image by Blausen.com staff (2014). \"Medical gallery of Blausen Medical 2014\"
Phagocytosis - C-reactive protein (CRP) is a substance made by the liver that is released into the bloodstream by inflammation and infection as part of the body's immune response.
C-reactive protein (CRP) is a substance made by the liver that is released into the bloodstream by inflammation and infection as part of the body's immune response. White blood cells are also mobilized by the immune system and CRP is believed to enhance the activity of the white blood cells called macrophages. Each type of white blood cell has its own specialized immune functions; macrophages, for example, basically engulf and \"eat\" foreign invaders such as bacteria, viruses and fungi. Macrophages in the spleen and the liver weed out old and defective red blood cells and break them into recyclables (iron, heme, and some globin) and wastes (such as bilirubin). The bilirubin is then used by the liver to produce bile, which is stored in the gallbladder and released into the small intestine to aid digestion.
Image by TheVisualMD
White blood cells
Immune cells surrounding hair follicles in mouse skin. These hair follicles are home to a diverse array of commensal bacteria.
Image by NIAID
Neutrophil
Neutrophil function, relationship to disease, and location in the human body. Credit: NIAID
Image by NIAID
Innate immune system
Image by US Gov
Macrophage Capturing Foreign Antigen
Cell-mediated immunity is an immune response that does not involve antibodies or complement but rather involves the activation of macrophages, natural killer cells (NK), antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. Macrophages are white blood cells that engulf and digest cellular debris and pathogens
Image by TheVisualMD
Mast Cell
Mast cells produce histamine. Histamine is known for its role in inflammation. It affects a variety of behavior patterns including the sleep-wake cycle and food intake. Antihistamines may work at odds with inflammation and depression.
Image by TheVisualMD
Leukocytes
Image by OpenStax College
Innate immune system
Illustration of the Innate Immune System responding to injury.
Image by OpenStax College
Eosinophilia
Drawing of an eosinophil white blood cell
Image by Iceclanl
Two neutrophils among many red blood cells. Neutrophils are one type of cell affected by chronic granulomatous disease.
Image by Uploaded by Mgiganteus
Eosinophils
Eosinophil function, relationship to disease, and location in the human body.
Image by NIAID
Sensitive content
This media may include sensitive content
Blood Cells
This is a scanning electron microscope image from normal circulating human blood. One can see red blood cells, several white blood cells including lymphocytes, amonocyte, a neutrophil, and many small disc-shaped platelets. Red cells are nonnucleated and contain hemoglobin, an important protein that contains iron and allows the cell to carry oxygen to other parts of the body. They also carry carbon dioxide away from peripheral tissue to the lungs where it can be exhaled. The infection-fighting white blood cells are classified in two main groups: granular and agranular. All blood cells are formed in the bone marrow. There are two types of agranulocytes: lymphocytes, which fight disease by producing antibodies and thus destroying foreign material, and monocytes. Platelets are tiny cells formed in bone marrow and are necessary for blood clotting.
Image by Bruce Wetzel (photographer). Harry Schaefer (photographer), National Cancer Institute
Immune System and Autoimmune Diseases
Normally, an individual's immune system learns to identify and ignore all of the distinctive little structures found on that individual's own cells. Sometimes, however, it will make a mistake and identify its own body as foreign. If that happens, the immune system produces antibodies that attempt to destroy the body's own cells in the same way it would try to destroy a foreign invader.
Image by TheVisualMD
Eosinophils
Drawing of an eosinophil white blood cell
Image by BruceBlaus
Eosinophils
On the left there is a segmented polymorphonuclear neutrophil, on the right and below is one eosinophil leucocyte. For comparison the red blood cell have a diameter of 7-8 micrometers. The picture was taken with a Nikon Eclipse 600 microscope, magnification was 1000x.
Image by Davidcsaba Dr. David Csaba L.
Neutrophil action - Inflammation
Neutrophil granulocyte migrates from the blood vessel to the matrix, secreting proteolytic enzymes, in order to dissolve intercellular connections (for improvement of its mobility) and envelop bacteria through Phagocytosis.
Image by Uwe Thormann/Wikimedia
Neutrophil
Image by BruceBlaus
White Blood Cells
A type of immune cell. Most white blood cells are made in the bone marrow and are found in the blood and lymph tissue. White blood cells help the body fight infections and other diseases. Granulocytes, monocytes, and lymphocytes are white blood cells.
Image by Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014"
high white blood cell count Video
Video by itbestshop/YouTube
What Are White Blood Cells | Health | Biology | FuseSchool
Video by FuseSchool - Global Education/YouTube
Learning to Decode Your Blood Test Results for Chronic Lymphocytic Leukemia (CLL)
Video by CLL Society/YouTube
WellnessFX: White Blood Cells And Differential with Bryan Walsh
Video by WellnessFX/YouTube
White Blood Count
White Blood Count
Image by TheVisualMD
White Blood Cell Count: Bone Marrow
TheVisualMD
White Blood Cells, Bone Marrow
TheVisualMD
2:12
Complete Blood Count, and Baselining Your Health
TheVisualMD
6:49
The Immune System Explained I – Bacteria Infection
Kurzgesagt – In a Nutshell/YouTube
1:47
Immune Response to Bacteria
NIAID/YouTube
14:59
Immunology - Adaptive Immune System
Armando Hasudungan/YouTube
3:02
Immune System - Natural Killer Cell
Kyle Thornthwaite/YouTube
15:02
Your Immune System: Natural Born Killer - Crash Course Biology #32
CrashCourse/YouTube
White Blood Cell and Red Blood Cell
TheVisualMD
White Blood Cell and Red Blood Cell
TheVisualMD
Red Blood Cell and White Blood Cell
TheVisualMD
Sensitive content
This media may include sensitive content
Blood cells (from left to right: erythrocyte, thrombocyte, leukocyte)
Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)
Bone structure
Smart Servier website
Blood Cells
Blausen.com staff (2014). \"Medical gallery of Blausen Medical 2014\"
Phagocytosis - C-reactive protein (CRP) is a substance made by the liver that is released into the bloodstream by inflammation and infection as part of the body's immune response.
TheVisualMD
White blood cells
NIAID
Neutrophil
NIAID
Innate immune system
US Gov
Macrophage Capturing Foreign Antigen
TheVisualMD
Mast Cell
TheVisualMD
Leukocytes
OpenStax College
Innate immune system
OpenStax College
Eosinophilia
Iceclanl
Two neutrophils among many red blood cells. Neutrophils are one type of cell affected by chronic granulomatous disease.
Uploaded by Mgiganteus
Eosinophils
NIAID
Sensitive content
This media may include sensitive content
Blood Cells
Bruce Wetzel (photographer). Harry Schaefer (photographer), National Cancer Institute
Immune System and Autoimmune Diseases
TheVisualMD
Eosinophils
BruceBlaus
Eosinophils
Davidcsaba Dr. David Csaba L.
Neutrophil action - Inflammation
Uwe Thormann/Wikimedia
Neutrophil
BruceBlaus
White Blood Cells
Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014"
8:22
high white blood cell count Video
itbestshop/YouTube
3:12
What Are White Blood Cells | Health | Biology | FuseSchool
FuseSchool - Global Education/YouTube
1:17:17
Learning to Decode Your Blood Test Results for Chronic Lymphocytic Leukemia (CLL)
CLL Society/YouTube
16:52
WellnessFX: White Blood Cells And Differential with Bryan Walsh
WellnessFX/YouTube
White Blood Count
TheVisualMD
Blood Differential Test
Blood Differential Test
Also called: White Blood Cell Differential, WBC Differential, Leukocyte Differential Count, Differential Blood Count
A blood differential test measures the different types of white blood cells in a sample of your blood: neutrophils, lymphocytes, monocytes, eosinophils, and basophils. The test helps diagnose infections, inflammation, immune diseases, cancer and other disorders.
Blood Differential Test
Also called: White Blood Cell Differential, WBC Differential, Leukocyte Differential Count, Differential Blood Count
A blood differential test measures the different types of white blood cells in a sample of your blood: neutrophils, lymphocytes, monocytes, eosinophils, and basophils. The test helps diagnose infections, inflammation, immune diseases, cancer and other disorders.
A blood differential test measures the amount of each type of white blood cell (WBC) that you have in your body. White blood cells (leukocytes) are part of your immune system, a network of cells, tissues, and organs that work together to protect you from infection. There are five different types of white blood cells:
Neutrophils are the most common type of white blood cell. They are your body's main defense against infection when bacteria, viruses, or other germs enter your body.
Lymphocytes include two main types of white blood cells: B cells and T cells. B cells fight off invading viruses, bacteria, or toxins. Certain T cells can target and destroy your body's own cells, such as cancer cells and cells that have been infected by viruses.
Monocytes kill bacteria, viruses, and other germs that may make you sick. They also boost your body's immune response and clear away dead cells.
Eosinophils defend against parasites and infections. They are also involved in allergies and help control inflammation (swelling and redness).
Basophils release enzymes during allergic reactions and asthma attacks.
However, your test results may have more than five numbers. For example, the lab may list the results as counts as well as percentages.
Other names for a blood differential test: Complete blood count (CBC) with differential, Differential, White blood cell differential count, Leukocyte differential count
A blood differential test is often part of a general physical exam. Because the five types of white blood cell do different jobs, measuring them separately can give your health care provider important information about your health.
The test can also help diagnose a variety of medical conditions, such as:
Infections
Autoimmune diseases
Inflammatory diseases
Leukemia and other types of cancer
A blood differential test is used for many reasons. Your provider may have ordered the test to:
Monitor your overall health or as part of a routine checkup.
Diagnose a medical condition when you have symptoms. For example, if you are feeling unusually tired or weak, or have unexplained bruising or other symptoms, this test may help uncover the cause.
Keep track of an existing blood disorder or related condition.
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
No special preparation is necessary.
There is very little risk to having a blood test. After the test, some people experience mild pain, dizziness, or bruising. These symptoms usually go away quickly.
There are many reasons your blood differential test results may be higher or lower than normal. For example, a high white blood cell count may mean you have an infection, an immune disorder, leukemia, or an allergic reaction. A low count may be caused by bone marrow problems, reactions to medicines, or cancer.
But abnormal results don't always mean you have a condition that needs medical treatment. Factors such as exercise, diet, alcohol level, medicines, and even a woman's menstrual period can affect the results.
If your results seem abnormal, your provider may order more specific tests to help figure out the cause. To learn what your results mean, talk with your provider.
Use of certain steroids may increase your white blood cell count, which can lead to an abnormal result in your blood differential test.
Blood Differential: MedlinePlus Medical Test [accessed on Jan 20, 2024]
Blood differential test: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
Additional Materials (1)
White blood cells
White blood cells (also called leukocytes) are in the front lines in the fight against harmful viruses, bacteria, and fungi. The white blood cell (WBC) count measures the total number of white blood cells per microliter (about a drop); a WBC count also indicates the relative numbers of each type of white blood cell present. There are many specific types of WBCs, grouped into five main categories: neutrophils (normally the most abundant), eosinophils, basophils, lymphocytes and monocytes (which give rise to macrophages, which can ingest foreign particles, including pathogens, in a process called phagocytosis).
Image by TheVisualMD
White blood cells
TheVisualMD
Neutrophils
Neutrophil Count
Also called: Neutrophils (Complete Blood Count), Neutrophils, Neutropenia Test, Neutrophilia Test
This test measures the amount of neutrophils in a sample of your blood. Neutrophils are the most common type of white blood cell. They are your body's main defense against infection when bacteria, viruses, or other germs enter your body. An abnormal level of neutrophils circulating in the blood could indicate a number of health issues.
Neutrophil Count
Also called: Neutrophils (Complete Blood Count), Neutrophils, Neutropenia Test, Neutrophilia Test
This test measures the amount of neutrophils in a sample of your blood. Neutrophils are the most common type of white blood cell. They are your body's main defense against infection when bacteria, viruses, or other germs enter your body. An abnormal level of neutrophils circulating in the blood could indicate a number of health issues.
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Use the slider below to see how your results affect your
health.
%
40
60
Your result is Normal.
About 40 to 60 percent of all white blood cells are neutrophils.
Related conditions
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Use the slider below to see how your results affect your
health.
10³/μL
1.8
7.8
Your result is Normal.
About 40 to 60 percent of all white blood cells are neutrophils. A normal neutrophil count for adults usually is between 1,800 and 7,800 neutrophils per microliter of blood.
Related conditions
A neutrophil is a type of immune cell that is one of the first cell types to travel to the site of an infection. Neutrophils help fight infection by ingesting microorganisms and releasing enzymes that kill the microorganisms. A neutrophil is a type of white blood cell, a type of granulocyte, and a type of phagocyte.
Neutrophils are the most abundant white blood cells, accounting for about 40% to 60% of all white blood cells circulating in the blood. Neutrophils are historically defined as "soldiers of our innate immune system." They are the first line of cells recruited at the site of infection and attack, ingest, and digest invading microorganisms, including fungi and bacteria. Failure to carry out this role leads to immunodeficiency, which is mainly characterized by the presence of recurrent infections.
Normally, most of the neutrophils circulating in the bloodstream are in a mature form, with the nucleus of the cell being divided or segmented. Because of the segmented appearance of the nucleus, neutrophils are sometimes referred to as "segs." The nucleus of less mature neutrophils is not segmented, but has a band or rod-like shape. Therefore, less mature neutrophils are known as band-form neutrophils or "bands".
The number of neutrophils in your blood is measured as part of a blood differential test.
A blood differential test is often part of a general physical exam. Because the different types of white blood cell do different jobs, measuring them separately can give your health care provider important information about your health.
The test can also help diagnose a variety of medical conditions, such as:
Infections
Autoimmune diseases
Inflammatory diseases
Leukemia and other types of cancer
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
No special preparation is necessary.
There is very little risk to having a blood test. After the test, some people experience mild pain, dizziness, or bruising. These symptoms usually go away quickly.
The results can be expressed as a percentage (of the total number of all white blood cells) or as an absolute value.
An increased neutrophil number in your blood, a condition called neutrophilia or neutrophilic leukocytosis, is usually the result of:
Acute infections, primarily by bacteria, less frequently by viruses or fungi.
Tissue inflammation, such as in inflammatory bowel disease or rheumatoid arthritis.
Tissue death (necrosis), caused either by trauma, heart attack, burns, or major surgery.
Blood cancer (leukemia).
Pregnancy, temporary during the last trimester or labor.
Severe stress.
Strenuous physical exercise.
A low neutrophil count in your blood, a condition called neutropenia, may be a consequence of:
Chemotherapy during cancer treatment.
Overwhelming infection (sepsis).
Negative reaction to some drugs.
Aplastic anemia (a condition where the body stops producing enough new blood cells).
Myelodysplastic syndrome (the bone marrow produce poorly formed blood cells or cells that don't work properly).
A small percentage of band-form neutrophils is normal in the blood. However, an increased count of these cells (bandemia) is referred to as “left shift” and can be caused by acute infection (sepsis) or inflammation (acute appendicitis or cholecystitis).
Blood Differential: MedlinePlus Medical Test [accessed on Jan 22, 2024]
Blood differential test: MedlinePlus Medical Encyclopedia [accessed on Jan 22, 2024]
White Blood Cell (WBC) Differential - Testing.com. Aug 7, 2022 [accessed on Jan 22, 2024]
DALE.DAVID. Neutropenia - Blood Disorders - MSD Manual Consumer Version [accessed on Jan 22, 2024]
DALE.DAVID. Neutrophilic Leukocytosis - Blood Disorders - MSD Manual Consumer Version [accessed on Jan 22, 2024]
Patrick M. Zito. Neutropenia. StatPearls Publishing. Aug 25, 2022 [accessed on Jan 22, 2024]
Farah Zahra. Neutrophilia. StatPearls Publishing. Apr 27, 2023 [accessed on Jan 22, 2024]
Complete Blood count with Differential [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (20)
Neutrophil granulocyte
Neutrophil granulocytes (also known as neutrophils) : Neutrophils with a segmented nuclei surrounded byerythrocytes, the intra-cellular granules are visible in the cytoplasm
Neutrophil
Neutrophil function, relationship to disease, and location in the human body. Credit: NIAID
Image by NIAID
Klebsiella pneumoniae Bacteria
Produced by the National Institute of Allergy and Infectious Diseases (NIAID), this digitally colorized scanning electron microscopic (SEM) image, depicts a blue-colored, human white blood cell, (WBC) known specifically as a neutrophil, interacting with two pink-colored, rod shaped, multidrug-resistant (MDR), Klebsiella pneumoniae bacteria, which are known to cause severe hospital acquired, nosocomial infections.
Image by David Dorward; Ph.D.; National Institute of Allergy and Infectious Diseases (NIAID)
White Blood Cell and Red Blood Cell
Medical visualization of blood cells. Depicted are numerous red blood cells and a single white blood cell.
Image by TheVisualMD
Hematopoeisis Diagram
Many cells can result from one stem cell. Because division can occur at different stages of the cell's development, a single cell has the potential to become eight to 32 RBCs.
Image by TheVisualMD
Neutrophil
The most abundant type of white blood cells. They are normally found in the blood stream however during the acute phase of inflammation, neutraphils leave the vasculature and migrate toward the site of inflammation in a process called chemotaxis.
Image by TheVisualMD
Anthrax - How People Are Infected?
Neutrophil engulfing anthrax bacteria : Neutrophil (yellow) engulfing anthrax bacteria (orange), taken with a Leo 1550 scanning electron microscope. Scale bar is 5 micrometers.
Image by Volker Brinkmann
Splenic infarction
Blood smear from an adult female with a myelodysplastic syndrome related to radiotherapy and chemotherapy for Hodgkin disease. A hypogranular neutrophil with a pseudo-Pelger-Huet nucleus is shown. The red blood cells show marked poikilocytosis, in part related to post-splenectomy status. (Wright-Giemsa stain).
Image by The Armed Forces Institute of Pathology (AFIP)
Inflammation
Illustration of the Inflammatory Process
Image by OpenStax College
Bone structure
Anatomy of the bone. The bone is made up of compact bone, spongy bone, and bone marrow. Compact bone makes up the outer layer of the bone. Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Image by Smart Servier website
Neutrophil
Image by BruceBlaus
Cell line plasma cells
Diagram showing the cell line plasma cells
Image by Cancer Research UK uploader
Neutrophils and How White Blood Cells Work
Video by TheCancer Immunity/YouTube
Extravasation of Neutrophils
Video by Katie Bergdale/YouTube
high white blood cell count Video
Video by itbestshop/YouTube
Learning to Decode Your Blood Test Results for Chronic Lymphocytic Leukemia (CLL)
Video by CLL Society/YouTube
Immune- Documentary - Part 4 - Neutrophils
Video by Rajesh kumar/YouTube
Neutrophils and Platelets: Why Are They Monitored So Closely?
Video by Patient Power - a Cancer Community/YouTube
Neutropenia - Mayo Clinic
Video by Mayo Clinic/YouTube
Neutropenia
Blood film with a striking absence of neutrophils, leaving only red blood cells and platelets
Image by Roberto J. Galindo
Neutrophil granulocyte
Neutrophil
NIAID
Klebsiella pneumoniae Bacteria
David Dorward; Ph.D.; National Institute of Allergy and Infectious Diseases (NIAID)
White Blood Cell and Red Blood Cell
TheVisualMD
Hematopoeisis Diagram
TheVisualMD
Neutrophil
TheVisualMD
Anthrax - How People Are Infected?
Volker Brinkmann
Splenic infarction
The Armed Forces Institute of Pathology (AFIP)
Inflammation
OpenStax College
Bone structure
Smart Servier website
Neutrophil
BruceBlaus
Cell line plasma cells
Cancer Research UK uploader
2:15
Neutrophils and How White Blood Cells Work
TheCancer Immunity/YouTube
2:27
Extravasation of Neutrophils
Katie Bergdale/YouTube
8:22
high white blood cell count Video
itbestshop/YouTube
1:17:17
Learning to Decode Your Blood Test Results for Chronic Lymphocytic Leukemia (CLL)
CLL Society/YouTube
1:58
Immune- Documentary - Part 4 - Neutrophils
Rajesh kumar/YouTube
3:37
Neutrophils and Platelets: Why Are They Monitored So Closely?
Patient Power - a Cancer Community/YouTube
6:37
Neutropenia - Mayo Clinic
Mayo Clinic/YouTube
Neutropenia
Roberto J. Galindo
Lymphocytes
Lymphocyte Count
Also called: Lymphocytes (Complete Blood Count), Lymphocytes, Lymphs, Lymphocytosis Test, Lymphocytopenia Test
This test measures the amount of lymphocytes in a sample of your blood. A lymphocyte is a type of white blood cell that is part of the immune system. It defends the body against infection, disease, and altered (mutated) cells. An abnormal level of lymphocytes circulating in the blood could indicate a number of health issues.
Lymphocyte Count
Also called: Lymphocytes (Complete Blood Count), Lymphocytes, Lymphs, Lymphocytosis Test, Lymphocytopenia Test
This test measures the amount of lymphocytes in a sample of your blood. A lymphocyte is a type of white blood cell that is part of the immune system. It defends the body against infection, disease, and altered (mutated) cells. An abnormal level of lymphocytes circulating in the blood could indicate a number of health issues.
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Use the slider below to see how your results affect your
health.
%{WBCs}
20
40
Your result is Normal.
About 20 to 40 percent of all white blood cells are lymphocytes.
Related conditions
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Use the slider below to see how your results affect your
health.
10³/μL
1
4.8
Your result is Normal.
About 20 to 40 percent of all white blood cells are lymphocytes. A normal lymphocyte count for adults usually is between 1,000 and 4,800 lymphocytes per microliter of blood.
Related conditions
A lymphocyte is a type of white blood cell that is part of the immune system. There are three types of lymphocytes. All lymphocytes help protect you from infection, but they have different functions.
B lymphocytes are made in the bone marrow. These cells make antibodies to help you get better when you are sick (humoral immunity). They also may protect you from future illness.
T lymphocytes develop in the thymus gland, an organ in the chest that is part of the lymphatic system. T cells can kill virus-infected cells or cancer cells and signal other cells to help destroy viruses (cellular immunity). T cells also help B cells form antibodies.
Natural killer cells, which develop in the bone marrow, thymus, and liver, are immune cells that contain enzymes to kill cancer cells or cells infected with a virus.
Lymphocytes account for about 20% to 40% of all white blood cells in the blood. Lymphocytes are responsible for the astonishing specificity of adaptive immune responses — they usually respond to foreign antigens only if the innate immune system is first activated. The innate immune system is the body's first line of defense against germs entering the body.
The number of lymphocytes in your blood is measured as part of a blood differential test.
A blood differential test is often part of a general physical exam. Because the different types of white blood cell do different jobs, measuring them separately can give your health care provider important information about your health.
The test can also help diagnose a variety of medical conditions, such as:
Infections
Autoimmune diseases
Inflammatory diseases
Leukemia and other types of cancer
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
No special preparation is necessary.
There is very little risk to having a blood test. After the test, some people experience mild pain, dizziness, or bruising. These symptoms usually go away quickly.
The results can be expressed as a percentage (of the total number of all white blood cells) or as an absolute value.
An increased number of lymphocytes in your blood, a condition called lymphocytosis or lymphocytic leukocytosis, can be the result of:
Chemotherapy
Infections, such as mononucleosis
Cancers, such as lymphoma or leukemia
Autoimmune disorders, such as Graves disease or Crohn disease
Radiation therapy or exposure
Severe sepsis
Steroid use
A decreased number of lymphocytes in your blood, a condition called lymphocytopenia, can be the result of:
Infections,such as HIV, viral hepatitis, influenza, COVID-19, tuberculosis, pneumonia, sepsis, or malaria
Autoimmune disorders, such as lupus or rheumatoid arthritis
Blood cancer and other blood diseases, such as Hodgkin's disease and aplastic anemia
Some medical treatments like blood and bone marrow transplant, cancer treatment, steroid therapy, or major surgery
Drinking too much alcohol or poor nutrition (having a diet without enough protein or other nutrients)
Certain inherited conditions, such as ataxia telangiectasia or SCID
If you have an abnormal lymphocytes count, your doctor may order a flow cytometry test. Flow cytometry can measure the levels of the different types of lymphocytes — T cells, B cells, and natural killer cells.
Blood Differential: MedlinePlus Medical Test [accessed on Jan 22, 2024]
Lymphopenia - What Is Lymphopenia? | NHLBI, NIH. May 31, 2022 [accessed on Jan 22, 2024]
Blood differential test: MedlinePlus Medical Encyclopedia [accessed on Jan 22, 2024]
White Blood Cell (WBC) Differential - Testing.com. Aug 7, 2022 [accessed on Jan 22, 2024]
Peter Walter. Lymphocytes and the Cellular Basis of Adaptive Immunity. Garland Science. Jan 22, 2024 [accessed on Jan 22, 2024]
DALE.DAVID. Lymphocytic Leukocytosis - Blood Disorders - MSD Manual Consumer Version [accessed on Jan 22, 2024]
DALE.DAVID. Lymphocytopenia - Blood Disorders - MSD Manual Consumer Version [accessed on Jan 22, 2024]
The innate and adaptive immune systems. Institute for Quality and Efficiency in Health Care (IQWiG). Jul 30, 2020 [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (12)
Lymphocyte migration.
Video by Immunology Toronto/YouTube
Lymphopaenia – What is a safe lymphocyte count? | Prof Gavin Giovannoni, MS Academy #MSCovid19
Video by Neurology Academy/YouTube
Pathway of stem cell differentiation
Pathway of stem cell differentiationFunding from the NIH Office of Research and Structured Programs (ORIP) to the Wisconsin National Primate Research Center to explore stem cell related solutions for Parkinson's disease."
Image by US Gov
Hematopoiesis
Diagram showing the development of different blood cells from haematopoietic stem cell to mature cells
Image by A. Rad
Human B Lymphocyte
B cell function, relationship to disease, and location in the human body.
Image by NIAID
Human B Lymphocyte
Transmission electron micrograph of a B cell from a human donor.
Image by NIAID
Healthy Human T Cell
Scanning electron micrograph of a human T lymphocyte (also called a T cell) from the immune system of a healthy donor.
Image by NIAID
Human B Lymphocyte
Colorized scanning electron micrograph of a B cell from a human donor.
Image by NIAID
T cell
T cell function, relationship to disease, and location in the human body. Credit: NIAID
Image by NIAID
3D illustration of a lymphocyte B cell
Image by Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436.
Lymphocyte
Electron microscopic image of a single human lymphocyte.
Image by Dr. Triche National Cancer Institute
Lymphatic System
Illustration of the Lymphatic System
Image by OpenStax College
2:32
Lymphocyte migration.
Immunology Toronto/YouTube
1:01:39
Lymphopaenia – What is a safe lymphocyte count? | Prof Gavin Giovannoni, MS Academy #MSCovid19
Neurology Academy/YouTube
Pathway of stem cell differentiation
US Gov
Hematopoiesis
A. Rad
Human B Lymphocyte
NIAID
Human B Lymphocyte
NIAID
Healthy Human T Cell
NIAID
Human B Lymphocyte
NIAID
T cell
NIAID
3D illustration of a lymphocyte B cell
Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436.
Lymphocyte
Dr. Triche National Cancer Institute
Lymphatic System
OpenStax College
Monocytes
Monocyte Count
Also called: Monocytes (Complete Blood Count), Monocytes, Monocytosis Test, Monocytopenia Test
This test measures the amount of monocytes in a sample of your blood. Monocytes are a type of white blood cell. They help fight off infections and play a role in your body's immune response. An abnormal level of monocytes in the blood could indicate a number of issues, including infection, autoimmune disorder, or certain type of cancer.
Monocyte Count
Also called: Monocytes (Complete Blood Count), Monocytes, Monocytosis Test, Monocytopenia Test
This test measures the amount of monocytes in a sample of your blood. Monocytes are a type of white blood cell. They help fight off infections and play a role in your body's immune response. An abnormal level of monocytes in the blood could indicate a number of issues, including infection, autoimmune disorder, or certain type of cancer.
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Use the slider below to see how your results affect your
health.
%{WBCs}
2
8
Your result is Normal.
About 2 to 8 percent of all white blood cells are monocytes.
Related conditions
{"label":"Monocytes (absolute count) reference range","scale":"lin","step":0.01,"hideunits":false,"items":[{"flag":"abnormal","label":{"short":"Low","long":"Low","orientation":"horizontal"},"values":{"min":0,"max":0.1},"text":"A decreased number of monocytes in your blood (monocytopenia) can occur due to several disorders or diseases. Talk to your doctor to know what your results mean in your specific case.","conditions":["Sepsis","Infections","Bone marrow disorders","Chemotherapy drugs"]},{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":0.1,"max":0.9},"text":"About 2 to 8 percent of all white blood cells are monocytes. A normal monocyte count for adults usually is between 100 and 900 monocytes per microliter of blood.","conditions":[]},{"flag":"abnormal","label":{"short":"High","long":"High","orientation":"horizontal"},"values":{"min":0.9,"max":2},"text":"An increased number of monocytes in your blood (monocytosis) can be caused by parasitic infections or other chronic conditions.","conditions":["Chronic inflammatory disease","Leukemia","Parasitic infection","Tuberculosis","Viral infection (for example, infectious mononucleosis, mumps, measles)"]}],"units":[{"printSymbol":"10\u00b3\/\u03bcL","code":"10*3\/uL","name":"thousand per microliter"}],"value":0.5}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your
health.
10³/μL
0.1
0.9
Your result is Normal.
About 2 to 8 percent of all white blood cells are monocytes. A normal monocyte count for adults usually is between 100 and 900 monocytes per microliter of blood.
Related conditions
A monocyte is a type of immune cell that is made in the bone marrow and travels through the blood to tissues in the body where it becomes a macrophage. Macrophages surround and kill microorganisms, ingest foreign material, remove dead cells, and boost immune responses. A monocyte is a type of white blood cell and a type of phagocyte.
Monocytes are the largest white blood cell, measuring between 12 to 20 µm in diameter, approximately twice the size of red blood cells. They account for approximately 2% to 8% of circulating white blood cells in normal adult blood.
The number of monocytes in your blood is measured as part of a blood differential test.
A blood differential test is often part of a general physical exam. Because the different types of white blood cell do different jobs, measuring them separately can give your health care provider important information about your health.
The test can also help diagnose a variety of medical conditions, such as:
Infections
Autoimmune diseases
Inflammatory diseases
Leukemia and other types of cancer
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
No special preparation is necessary.
There is very little risk to having a blood test. After the test, some people experience mild pain, dizziness, or bruising. These symptoms usually go away quickly.
The results can be expressed as a percentage (of the total number of all white blood cells) or as an absolute value.
An increased number of monocytes in your blood, a condition called monocytosis, may be due to:
Chronic inflammatory disease
Leukemia
Parasitic infection
Tuberculosis
Viral infection (for example, infectious mononucleosis, mumps, or measles)
A decreased number of monocytes in your blood, a condition called monocytopenia, can occur due to severe blood infections (sepsis), bone marrow disorders, or chemotherapy treatment. In some cases, people with human papillomavirus (HPV) infection of the genitals, and people with certain skin infections can also have a low number of monocytes.
After a few hours in the bloodstream, monocytes travel to some organs such as lungs, liver, spleen and bone marrow tissue, where they convert into macrophages. Macrophages are considered to be the main “hunter” cell of the immune system.
Rare cases have been described where people have a complete absence of monocytes, this is known as MonoMAC syndrome. The cause is usually a genetic bone marrow disorder, and its manifestations may vary. The affected person can contract skin infections by organisms that in healthy people does not normally cause infections, they can develop some forms of cancer, and without treatment the result if fatal. Treatment is by performing a bone marrow transplant.
Blood Differential: MedlinePlus Medical Test [accessed on Jan 22, 2024]
Blood differential test: MedlinePlus Medical Encyclopedia [accessed on Jan 22, 2024]
White Blood Cell (WBC) Differential - Testing.com. Aug 7, 2022 [accessed on Jan 22, 2024]
DALE.DAVID. Monocyte Disorders - Blood Disorders - MSD Manual Consumer Version [accessed on Jan 22, 2024]
Prabhu D. Emmady. Histology, Monocytes. StatPearls Publishing. Apr 24, 2023 [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (17)
White Blood Cells Rotation
This rotational interactive features five white blood cells. At the top left is a neutrophil (purple nucleus); center is a Monocyte-macrophage (orange nucleus); top right is a Lymphocyte (red nucleus); bottom left a Basophil (green nucleus); and bottom right an Eosinophil (yellow nucleus). These molecules are all part of a white blood cell count test. A white blood cell count is an important measure of this key component of the immune system; when the body is under attack, more WBCs are produced. White blood cells (also called leukocytes or WBCs) are in the front lines in the fight against harmful viruses, bacteria and even fungus. A white blood cell count is an important measure of this key component of the immune system; when the body is under attack, more WBCs are produced. Other factors, however, may also affect WBC counts, including allergies, chemotherapy, and other drugs, as well as leukemia.
Image by TheVisualMD
White Blood Cells, Bone Marrow
Bone marrow is constantly producing blood cells, including white blood cells and red blood cells as well platelets, which are cell fragments important for blood clotting. Disease and disorders of the bone marrow can, in turn, affect the production of blood cells. Both cancer and cancer treatment (chemotherapy and radiation) can also have an impact on the bone marrow's ability to produce blood cells.
Image by TheVisualMD
This browser does not support the video element.
Complete Blood Count, and Baselining Your Health
Video Topics : Our lifeblood consists of many components and a complete blood count (CBC) includes measurements of the fundamental elements. The largest categories are red and white blood cells (RBCs and WBCs) and cell fragments called platelets, which play roles in blood clotting. There are 20-30 trillion red blood cells in the body of an adult, each with a lifespan of about 100 days (RBCs contain an iron-containing protein called hemoglobin that enables them to carry oxygen to tissues throughout the body and then return carbon dioxide to the lungs). WBCs are in the front lines in the body's ongoing fight against harmful viruses, bacteria and even fungus; when a pathogen enters the body, WBCs mobilize in a coordinated defense response to eliminate, neutralize or mark the invader for destruction. The liquid portion of blood is called plasma and it carries nutrients, electrolytes, waste products, and hormones.
Video by TheVisualMD
What Does My White Blood Cell Count Tell My Healthcare Team?
Video by Diverse Health Hub/YouTube
The Immune System Explained I – Bacteria Infection
Video by Kurzgesagt – In a Nutshell/YouTube
White Blood Cells
A type of immune cell. Most white blood cells are made in the bone marrow and are found in the blood and lymph tissue. White blood cells help the body fight infections and other diseases. Granulocytes, monocytes, and lymphocytes are white blood cells.
Image by Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014"
Macrophage
Macrophages are mature forms of monocytes. Similar to the monocyte, it protects the body against blood-borne pathogens. They continue to destroy pathogens and cellular debris by ingesting them.
Image by TheVisualMD
Innate immune system
Image by US Gov
Skin After Injury
Basophils, mast cells, and red blood cells are joined within one hour of the injuring by bacteria-eating cells called phagocytes, which include neutrophils and monocytes.
Image by TheVisualMD
Subsiding Inflammation in blood vessels
Monocytes, having matured into macrophages continue to destroy pathogens and cellular debris by ingesting them, while the inflammation process begins to subside.
Image by TheVisualMD
White blood cells
Immune cells surrounding hair follicles in mouse skin. These hair follicles are home to a diverse array of commensal bacteria.
Image by NIAID
White Blood Cells
Immune cells surrounding hair follicles in mouse skin. These hair follicles are home to a diverse array of commensal bacteria.
Image by NIAID
Innate immune system
Illustration of the Innate Immune System responding to injury.
Image by OpenStax College
Bone structure
Anatomy of the bone. The bone is made up of compact bone, spongy bone, and bone marrow. Compact bone makes up the outer layer of the bone. Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Image by Smart Servier website
White Blood Cells
Title Normal Plasma Blood Cells. Description A normal plasma cell, a type of white blood cell, that helps to protect the body from germs and other harmful substances.
Image by Lydia Kibiuk (Illustrator) / National Cancer Institute
Monocytes
A monocyte is a leukocyte. It protects the body against blood-borne pathogens and moves quickly to sites of infection in the tissues. They are responsible for phagocytosis (ingestion) of foreign substances in the body.
Image by BruceBlaus
Sensitive content
This media may include sensitive content
Blood cells (from left to right: erythrocyte, thrombocyte, leukocyte)
A single drop of blood contains millions of red blood cells, white blood cells, and platelets. One of each type is shown here, isolated from a scanning electron micrograph.
Image by Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)
White Blood Cells Rotation
TheVisualMD
White Blood Cells, Bone Marrow
TheVisualMD
2:12
Complete Blood Count, and Baselining Your Health
TheVisualMD
5:01
What Does My White Blood Cell Count Tell My Healthcare Team?
Diverse Health Hub/YouTube
6:49
The Immune System Explained I – Bacteria Infection
Kurzgesagt – In a Nutshell/YouTube
White Blood Cells
Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014"
Macrophage
TheVisualMD
Innate immune system
US Gov
Skin After Injury
TheVisualMD
Subsiding Inflammation in blood vessels
TheVisualMD
White blood cells
NIAID
White Blood Cells
NIAID
Innate immune system
OpenStax College
Bone structure
Smart Servier website
White Blood Cells
Lydia Kibiuk (Illustrator) / National Cancer Institute
Monocytes
BruceBlaus
Sensitive content
This media may include sensitive content
Blood cells (from left to right: erythrocyte, thrombocyte, leukocyte)
Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)
Eosinophils
Eosinophil Count
Also called: Eosinophils (Complete Blood Count), Eosinophils, Eosins, Eos, Eosinopenia Test, Eosinophilia Test
This test measures the amount of eosinophils in a sample of your blood. Eosinophils are a type of white blood cell. They help fight off infections and play a role in your body's immune response. An abnormal level of eosinophils in the blood could indicate a number of issues, including infection, allergic reaction, and asthma.
Eosinophil Count
Also called: Eosinophils (Complete Blood Count), Eosinophils, Eosins, Eos, Eosinopenia Test, Eosinophilia Test
This test measures the amount of eosinophils in a sample of your blood. Eosinophils are a type of white blood cell. They help fight off infections and play a role in your body's immune response. An abnormal level of eosinophils in the blood could indicate a number of issues, including infection, allergic reaction, and asthma.
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Use the slider below to see how your results affect your
health.
%{WBCs}
1
4
Your result is Normal.
Normally your blood doesn't have a large number of eosinophils, accounting for 1% to 4% of the total circulating white blood cells.
Related conditions
{"label":"Eosinophils (absolute count) reference range","scale":"lin","step":0.01,"hideunits":false,"items":[{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":0,"max":0.45},"text":"About 1 to 4 percent of all white blood cells are eosinophils. A normal eosinophil count for adults usually is less than 450 eosinophils per microliter of blood.","conditions":[]},{"flag":"abnormal","label":{"short":" High","long":" High","orientation":"horizontal"},"values":{"min":0.45,"max":1.5},"text":"A high eosinophil count, known as eosinophilia, may indicate an allergic condition or an infection.","conditions":["Addison disease","Allergic reaction","Cancer","Chronic myelogenous leukemia","Collagen vascular disease","Hypereosinophilic syndromes","Parasitic infection"]},{"flag":"abnormal","label":{"short":"Very high","long":"Very high","orientation":"horizontal"},"values":{"min":1.5,"max":10},"text":"A high eosinophil count, known as eosinophilia, may indicate an allergic condition or an infection.","conditions":["Addison disease","Allergic reaction","Cancer","Chronic myelogenous leukemia","Collagen vascular disease","Hypereosinophilic syndromes","Parasitic infection"]}],"units":[{"printSymbol":"10\u00b3\/\u03bcL","code":"10*3\/uL","name":"thousand per microliter"}],"value":0.22}[{"normal":0},{"abnormal":0},{"abnormal":1}]
Use the slider below to see how your results affect your
health.
10³/μL
0.45
1.5
Your result is Normal.
About 1 to 4 percent of all white blood cells are eosinophils. A normal eosinophil count for adults usually is less than 450 eosinophils per microliter of blood.
Related conditions
An eosinophil is a type of immune cell that has granules (small particles) with enzymes that are released during infections, allergic reactions, and asthma. They can also build up and cause inflammation. An eosinophil is a type of white blood cell and a type of granulocyte.
Normally your blood doesn't have a large number of eosinophils, accounting for 1% to 4% of the total circulating white blood cells. Eosinophils become active when you have certain allergic diseases, infections, and other medical conditions. In some conditions, the eosinophils can move outside the bloodstream and build up in organs and tissues. This can happen in many different parts of the body, including the esophagus, heart, lungs, blood, and intestines.
The number of eosinophil in your blood is measured as part of a blood differential test.
A blood differential test is often part of a general physical exam. Because the different types of white blood cell do different jobs, measuring them separately can give your health care provider important information about your health.
The test can also help diagnose a variety of medical conditions, such as:
Infections
Autoimmune diseases
Inflammatory diseases
Leukemia and other types of cancer
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
No special preparation is necessary.
There is very little risk to having a blood test. After the test, some people experience mild pain, dizziness, or bruising. These symptoms usually go away quickly.
The results can be expressed as a percentage (of the total number of all white blood cells) or as an absolute value.
A higher than normal eosinophil count, known as eosinophilia, is usually due to:
Addison disease
Allergies (such as allergic rhinitis, eczema, or atopic dermatitis)
Asthma
Parasitic infestation
Fungus infection
Leukemia or other blood disorders
Hypereosinophilic syndrome
A lower than normal eosinophil count, known as eosinopenia, is less frequent and may be the consequence of:
Alcohol intoxication
Severe infections (e.g., sepsis)
Hormone-secreting tumors
Treatment with drugs known as corticosteroids
Your symptoms may vary depending on the affected organs:
Skin: you may have a rash.
Throat: pain or itchiness.
Eyes: redness, itchiness.
Lungs: shortness of breath, cough, and wheezing.
Stomach: pain.
Intestines: diarrhea.
Nevertheless, a slightly elevated or low eosinophils count does not usually cause any symptoms, and this is an accidental finding when a complete blood count test is done for any other reason.
Idiopathic hypereosinophilic syndrome is an uncommon condition in which the eosinophil count is very high, reaching levels of 1500 cells per microliter, for more than 6 months without a doctor being able to find a cause for it.
The increased number of eosinophils inflame tissues and can even cause organ damage to the lungs, heart, liver, nervous system, or skin. A small percentage of people can improve without any medical intervention; but without treatment, it can be fatal in up to 80% of people.
Blood Differential: MedlinePlus Medical Test [accessed on Jan 22, 2024]
Eosinophilic Disorders | Eosinophilia | MedlinePlus. National Library of Medicine. Mar 29, 2017 [accessed on Jan 22, 2024]
Blood differential test: MedlinePlus Medical Encyclopedia [accessed on Jan 22, 2024]
Differential Blood Count: Reference Range, Interpretation, Collection and Panels. Oct 24, 2023 [accessed on Jan 22, 2024]
White Blood Cell (WBC) Differential - Testing.com. Aug 7, 2022 [accessed on Jan 22, 2024]
DALE.DAVID. Eosinophilic Disorders - Blood Disorders - Merck Manuals Consumer Version [accessed on Jan 22, 2024]
Eosinophil count - absolute: MedlinePlus Medical Encyclopedia [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (9)
Eosinophilic Disorders... Made simple
Video by MadBlasta/YouTube
Blood Cell Bakery--Eosinophils
Video by sciencegoddess1/YouTube
What Does My White Blood Cell Count Tell My Healthcare Team?
Video by Diverse Health Hub/YouTube
Granulocytes
Diagram showing the cell line plasma cells come from
Image by Cancer Research UK uploader
Granulocytes
Granulocytes can be distinguished by the number of lobes in their nuclei and the staining properties of their granules. (credit “neutrophil” micrograph: modification of work by Ed Uthman)
Image by CNX/OpenStax
Eosinophils
Histological blood smear of an Eosinophil surrounded by Red Blood Cells and Platelets
Image by Iceclanl
Eosinophils
On the left there is a segmented polymorphonuclear neutrophil, on the right and below is one eosinophil leucocyte. For comparison the red blood cell have a diameter of 7-8 micrometers. The picture was taken with a Nikon Eclipse 600 microscope, magnification was 1000x.
Image by Davidcsaba Dr. David Csaba L.
Eosinophils
Eosinophil function, relationship to disease, and location in the human body.
Image by NIAID
Eosinophil
Visualization of a eosinophil. A type of white blood cell responsible for combating infection. They make up 2% of all white blood cells.
Image by TheVisualMD
2:14
Eosinophilic Disorders... Made simple
MadBlasta/YouTube
1:08
Blood Cell Bakery--Eosinophils
sciencegoddess1/YouTube
5:01
What Does My White Blood Cell Count Tell My Healthcare Team?
Diverse Health Hub/YouTube
Granulocytes
Cancer Research UK uploader
Granulocytes
CNX/OpenStax
Eosinophils
Iceclanl
Eosinophils
Davidcsaba Dr. David Csaba L.
Eosinophils
NIAID
Eosinophil
TheVisualMD
Basophils
Basophil Count
Also called: Basophils (Complete Blood Count), Basophils, Basos, Basopenia Test, Basoophilia Test
This test measures the amount of basophils in a sample of your blood. Basophils, a type of white blood cell, release enzymes during allergic reactions and asthma attacks. An abnormal level of basophils circulating in the blood could indicate a number of health issues.
Basophil Count
Also called: Basophils (Complete Blood Count), Basophils, Basos, Basopenia Test, Basoophilia Test
This test measures the amount of basophils in a sample of your blood. Basophils, a type of white blood cell, release enzymes during allergic reactions and asthma attacks. An abnormal level of basophils circulating in the blood could indicate a number of health issues.
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Use the slider below to see how your results affect your
health.
%{WBCs}
0.1
1
Your result is Normal.
Less than 1 percent of all white blood cells are basophils.
Related conditions
{"label":"Basophils (absolute count) reference range","scale":"lin","step":0.01,"hideunits":false,"items":[{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":0,"max":0.2},"text":"Less than 1 percent of all white blood cells are basophils. A normal basophil count for adults usually is less than 200 basophils per microliter of blood.","conditions":[]},{"flag":"abnormal","label":{"short":"High","long":"High","orientation":"horizontal"},"values":{"min":0.2,"max":0.5},"text":"A higher-than-normal basophil count is known as basophilia. Basophilia can be caused by a wide variety of conditions, such as allergic reactions, asthma, and rheumatoid arthritis, among others.","conditions":["After splenectomy","Allergic reaction","Chronic myelogenous leukemia (a type of bone marrow cancer)","Collagen vascular disease","Myeloproliferative diseases (group of bone marrow diseases)","Chickenpox"]}],"units":[{"printSymbol":"10\u00b3\/\u03bcL","code":"10*3\/uL","name":"thousand per microliter"}],"value":0.1}[{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your
health.
10³/μL
0.2
Your result is Normal.
Less than 1 percent of all white blood cells are basophils. A normal basophil count for adults usually is less than 200 basophils per microliter of blood.
Related conditions
A basophil is a type of immune cell that has granules (small particles) with enzymes that are released during allergic reactions and asthma. A basophil is a type of white blood cell and a type of granulocyte.
Basophils are the least abundant white blood cells primarily found in the circulation. Normally, they comprise only a small percentage (0.5% to 1%) of the total circulating white blood cells, but rapidly expand in the bone marrow in response to inflammatory signals and are mobilized to the blood, spleen, lung and liver.
The number of basophils in your blood is measured as part of a blood differential test.
A blood differential test is often part of a general physical exam. Because the different types of white blood cell do different jobs, measuring them separately can give your health care provider important information about your health.
The test can also help diagnose a variety of medical conditions, such as:
Infections
Autoimmune diseases
Inflammatory diseases
Leukemia and other types of cancer
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
No special preparation is necessary.
There is very little risk to having a blood test. After the test, some people experience mild pain, dizziness, or bruising. These symptoms usually go away quickly.
The results can be expressed as a percentage (of the total number of all white blood cells) or as an absolute value.
An increased number of basophils in your blood, known as basophilia, may be due to:
After splenectomy
Allergic reaction
Chronic myelogenous leukemia
Collagen vascular disease
Myeloproliferative diseases (such as polycythemia vera and myelofibrosis)
Chickenpox
A decreased number of basophils in your blood, known as basopenia, may be due to:
Acute infection
Cancer
Severe injury
Blood Differential: MedlinePlus Medical Test [accessed on Jan 22, 2024]
Blood differential test: MedlinePlus Medical Encyclopedia [accessed on Jan 22, 2024]
Basophil (close-up): MedlinePlus Medical Encyclopedia Image [accessed on Jan 22, 2024]
DALE.DAVID. Basophilic Disorders - Blood Disorders - MSD Manual Consumer Version [accessed on Jan 22, 2024]
Graham LeGros. Understanding the roles of basophils: breaking dawn. Immunology. Mar 1, 2012. doi:10.1111/j.1365-2567.2011.03530.x [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (12)
White Blood Cells Rotation
This rotational interactive features five white blood cells. At the top left is a neutrophil (purple nucleus); center is a Monocyte-macrophage (orange nucleus); top right is a Lymphocyte (red nucleus); bottom left a Basophil (green nucleus); and bottom right an Eosinophil (yellow nucleus). These molecules are all part of a white blood cell count test. A white blood cell count is an important measure of this key component of the immune system; when the body is under attack, more WBCs are produced. White blood cells (also called leukocytes or WBCs) are in the front lines in the fight against harmful viruses, bacteria and even fungus. A white blood cell count is an important measure of this key component of the immune system; when the body is under attack, more WBCs are produced. Other factors, however, may also affect WBC counts, including allergies, chemotherapy, and other drugs, as well as leukemia.
Image by TheVisualMD
White Blood Cells, Bone Marrow
Bone marrow is constantly producing blood cells, including white blood cells and red blood cells as well platelets, which are cell fragments important for blood clotting. Disease and disorders of the bone marrow can, in turn, affect the production of blood cells. Both cancer and cancer treatment (chemotherapy and radiation) can also have an impact on the bone marrow's ability to produce blood cells.
Image by TheVisualMD
This browser does not support the video element.
Complete Blood Count, and Baselining Your Health
Video Topics : Our lifeblood consists of many components and a complete blood count (CBC) includes measurements of the fundamental elements. The largest categories are red and white blood cells (RBCs and WBCs) and cell fragments called platelets, which play roles in blood clotting. There are 20-30 trillion red blood cells in the body of an adult, each with a lifespan of about 100 days (RBCs contain an iron-containing protein called hemoglobin that enables them to carry oxygen to tissues throughout the body and then return carbon dioxide to the lungs). WBCs are in the front lines in the body's ongoing fight against harmful viruses, bacteria and even fungus; when a pathogen enters the body, WBCs mobilize in a coordinated defense response to eliminate, neutralize or mark the invader for destruction. The liquid portion of blood is called plasma and it carries nutrients, electrolytes, waste products, and hormones.
Video by TheVisualMD
What Does My White Blood Cell Count Tell My Healthcare Team?
Video by Diverse Health Hub/YouTube
Basophil
Visualization of a basophil. A type of leukocyte (white blood cell) responsible for combating infection.
Image by TheVisualMD
Basophil
Visualization of a basophil. A type of leukocyte (white blood cell) responsible for combating infection. Basophils are the least common of the granulocytes, representing about 0.01% to 0.3% of circulating leukocytes (white blood cells). They contain large cytoplasmic granules which obscure the cell nucleus under the microscope.
Image by BruceBlaus
Basophil
Basophil function, relationship to disease, and location in the human body.
Image by NIAID/NIH
Bone structure
Anatomy of the bone. The bone is made up of compact bone, spongy bone, and bone marrow. Compact bone makes up the outer layer of the bone. Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Image by Smart Servier website
Granulocytes
Granulocytes can be distinguished by the number of lobes in their nuclei and the staining properties of their granules. (credit “neutrophil” micrograph: modification of work by Ed Uthman)
Image by CNX/OpenStax
MastBasophilCells
Mast cells function similarly to basophils by inducing and promoting inflammatory responses. (a) This figure shows mast cells in blood. In a blood smear, they are difficult to differentiate from basophils (b). Unlike basophils, mast cells migrate from the blood into various tissues.
Image by modification of work by Greenland JR, Xu X, Sayah DM, Liu FC, Jones KD, Looney MR, Caughey GH)
hematopoietic stem cells (HSCs)
All the formed elements of the blood arise by differentiation of hematopoietic stem cells in the bone marrow.
Image by CNX/OpenStax
Blood Cells
Formed elements of blood include erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.
Image by OpenStax
White Blood Cells Rotation
TheVisualMD
White Blood Cells, Bone Marrow
TheVisualMD
2:12
Complete Blood Count, and Baselining Your Health
TheVisualMD
5:01
What Does My White Blood Cell Count Tell My Healthcare Team?
Diverse Health Hub/YouTube
Basophil
TheVisualMD
Basophil
BruceBlaus
Basophil
NIAID/NIH
Bone structure
Smart Servier website
Granulocytes
CNX/OpenStax
MastBasophilCells
modification of work by Greenland JR, Xu X, Sayah DM, Liu FC, Jones KD, Looney MR, Caughey GH)
hematopoietic stem cells (HSCs)
CNX/OpenStax
Blood Cells
OpenStax
Red Blood Cell (RBC) Count
Red Blood Cell (RBC) Count
Also called: Erythrocyte Count, RBC Count, Red Blood Count, Red Blood Cell Count, Red Count
A red blood cell (RBC) count is a blood test that measures the number of red blood cells in your blood. Red blood cells carry oxygen from your lungs to the rest of your body. An abnormal RBC count can be a sign of a serious health problem.
Red Blood Cell (RBC) Count
Also called: Erythrocyte Count, RBC Count, Red Blood Count, Red Blood Cell Count, Red Count
A red blood cell (RBC) count is a blood test that measures the number of red blood cells in your blood. Red blood cells carry oxygen from your lungs to the rest of your body. An abnormal RBC count can be a sign of a serious health problem.
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Use the slider below to see how your results affect your
health.
(10<sup>6</sup>)/μL
3.9
5.5
Your result is Normal.
Red blood cells (RBC) are made in the bone marrow and contain hemoglobin, a protein that carries oxygen to the tissues in the body. RBCs make up approximately 44% of the total blood volume.
Related conditions
A red blood cell (RBC) count measures the number of red blood cells, also known as erythrocytes, in your blood. Red blood cells carry oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, reproduce, and stay healthy. An RBC count that is higher or lower than normal is often the first sign of an illness. So the test may allow you to get treatment even before you have symptoms.
Other names: erythrocyte count, red count
A red blood cell (RBC) count is almost always part of a complete blood count, a group of tests that measure many different parts and features of your blood. The RBC measurement is used to help diagnose red blood cell disorders, such as anemia, a condition in which your body does not make enough healthy red blood cells.
You may get this test as part of a complete blood count, which is often included in a routine checkup. You may also need this test if you have symptoms of a low or high red blood cell count.
Symptoms of a low red blood cell count include:
Weakness
Fatigue
Pale skin
Rapid heartbeat
Symptoms of a high red blood cell count include:
Headache
Dizziness
Vision problems
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
You don't need any special preparations for a red blood cell (RBC) count.
There is very little risk to having a blood test. There may be slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
Your results will show whether you have a normal red blood cell count or a count that is too low or too high.
A low red blood cell count can be a sign of:
Anemia
Leukemia, a type of blood cancer
Malnutrition, a condition in which your body does not get the calories, vitamins, and/or minerals needed for good health
Multiple myeloma, a cancer of the bone marrow
Kidney failure
It may also be a sign of pregnancy.
A high red blood cell count can be a sign of:
Dehydration
Heart disease
Polycythemia vera, a bone marrow disease that causes too many red blood cells to be made
Scarring of the lungs, often due to cigarette smoking
Lung disease
Kidney cancer
If you have questions about your results, talk to your health care provider.
If results showed you had a low or a high red blood cell count, you may need more tests to help make a diagnosis. These include:
Reticulocyte count, a test that counts the number of reticulocytes in the blood. Reticulocytes are red blood cells that are still developing. These are also known as immature red blood cells.
Iron tests, which measure iron levels in the blood. Iron is essential for making red blood cells.
Vitamin B test, which measures the amount of one or more B vitamins in the blood. B vitamins are important for making red blood cells.
Red Blood Cell (RBC) Count: MedlinePlus Medical Test [accessed on Jan 20, 2024]
RBC count: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
Red Blood Cell Count (RBC) Test - Testing.com. Sep 27, 2022 [accessed on Jan 20, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (19)
Red blood cells
Red blood cells
Image by John Kalekos of Massachusetts image distribution for Science and Learning
Red Blood Cell
This image shows two red blood cells. The red blood cell is also called an erythrocyte: erythro is Greek for \"red,\" cyte is Latin for \"cell.\" The disc-shaped RBCs have the critical job of transporting oxygen from the lungs to the body's cells and bringing carbon dioxide from the cells back to the lungs to be expelled.
Image by TheVisualMD
Red Blood Cell in Capillary
The cardiovascular system is vast network of arteries, veins and vessels that would extend 60,000 miles if stretched end-to-end. All but a tiny fraction of this vessel network is invisible to the naked eye. The smallest capillaries (from latin "hairlike") are so narrow that red blood cells must pass through in single file. Higher than normal blood iron levels have been linked to heart disease and the reason is believed to be the oxidative stress the excess iron places on the walls of the blood vessels. It is the biological counterpart of rust. There are 20-30 trillion red blood cells (RBCs) in an adult's body. The life span of RBCs, which are produced in bone marrow, is about 100 days, which means that 2 million die (and are replaced) each second, but in that short lifetime they can make 75,000 round trips between lungs, heart and tissues in the body.
Image by TheVisualMD
Blood Smear Showing Reduced Red Blood Cell Count
Individual blood cells were first detected and described in the 17th century. Later, red blood cells (RBCs) were counted manually from a blood smear, a thin film of blood prepared on a glass slide and examined under a microscope (blood analysis is now automated, though smears are still used to detect visible abnormalities and to check or confirm the results of other tests). Anemia results when there are too few RBCs in circulation because they are being destroyed too quickly or produced too slowly. Anemia can be temporary or long term and range from mild to severe. Folate (also known as vitamin B9) is necessary for red blood cell production and the prevention of anemia, as well as the metabolism of carbohydrates. But folate also plays key roles in the synthesis and maintenance of DNA and is especially important in cell division and growth in fetal development (deficiencies of the vitamin in pregnancy is a common cause of birth defects). Pernicious anemia is a disorder in which the body's loses its ability to utilize folate and vitamin B12.
Image by TheVisualMD
Red Blood Cell (RBC)
There are 20-30 trillion red blood cells (RBCs) in an adult's body. The life span of RBCs, which are produced in bone marrow, is about 100 days, which means that 2 million die (and are replaced) each second. In their short lifetimes, however, red blood cells can make 75,000 round trips between lungs, heart and tissues in the body.
Image by TheVisualMD
Red Blood Cell
The RBC is disc-shaped and concave on both sides. The concave shape increases the cells' surface area, which allows them to distribute more oxygen to the body's cells. The shape also enables the cells to bunch together more compactly, helping them travel through the bloodstream more efficiently. Some RBCs are a bit thicker or thinner, wider or longer than others, but can change their shape to suit the demands of their environment. The cell membranes of the RBCs are protein meshes that give them flexibility, allowing them to navigate the twists and turns of the blood vessel network. The nearly 300 million hemoglobin molecules contained within each RBC easily move and slide past each other within the cell, adjusting their positions to conform to the RBC's shifting shape. Diameter : 7 μm
Image by TheVisualMD
Capillary Revealing Red Blood Cell
A portion of a capillary wall has been cut away to reveal the red blood cells flowing within.
Image by TheVisualMD
Red Blood Cell and White Blood Cell
Medical visualization of red blood cells and leukocytes.
Image by TheVisualMD
Blood Smear Showing Normal Red Blood Cell Count
Individual blood cells were first detected and described in the 17th century. Later, red blood cells were counted manually from a blood smear, a thin film of blood prepared on a glass slide and examined under a microscope. Blood analysis is now automated, though blood smears are still used to detect visible abnormalities and to check or confirm the results of other tests. There are normally between 4.2-5.8 million red blood cells per microliter (about a drop), which means there are 20-30 trillion red blood cells circulating through the body of an adult.
Image by TheVisualMD
Tubule of Nephron Revealing Many Red Blood Cell
This image shows the cut distal convoluted tubule of nephron with surrounding capillaries cut to reveal many red blood cells and healthy amounts of Erythopoeitin, EPO, (yellow particles). Erythropoeitin, EPO, is produced by the endothelial cells of the capillaries and the fibroblasts in the interstitial tissue surrounding the distal tubules. Normally, the kidneys produce EPO in response to low oxygen levels in order to stimulate red blood cell production in the bone marrow. A normal amount of red blood cells allows for the delivery of an adequate supply of oxygen.
Image by TheVisualMD
Red Blood Cell in Capillary
This image shows red blood cells traveling through capillaries, the smallest blood vessels in the body.
Image by TheVisualMD
Tubule of Nephron Revealing Few Red Blood Cell
Our kidneys are remarkable filters. Each day, they filter about 200 quarts of blood to extract about 2 quarts of wastes, which is then eliminated as urine. The kidneys' delicate filtration units are called nephrons; each kidney has about a million nephrons, and within each nephron are dense forests of tiny capillaries called glomeruli, which remove waste products from the blood while preventing the loss of other components, including proteins, electrolytes and blood cells. The glomerular filtration rate is the amount of blood that is filtered by the glomeruli per minute.
Image by TheVisualMD
This browser does not support the video element.
Complete Blood Count, and Baselining Your Health
Video Topics : Our lifeblood consists of many components and a complete blood count (CBC) includes measurements of the fundamental elements. The largest categories are red and white blood cells (RBCs and WBCs) and cell fragments called platelets, which play roles in blood clotting. There are 20-30 trillion red blood cells in the body of an adult, each with a lifespan of about 100 days (RBCs contain an iron-containing protein called hemoglobin that enables them to carry oxygen to tissues throughout the body and then return carbon dioxide to the lungs). WBCs are in the front lines in the body's ongoing fight against harmful viruses, bacteria and even fungus; when a pathogen enters the body, WBCs mobilize in a coordinated defense response to eliminate, neutralize or mark the invader for destruction. The liquid portion of blood is called plasma and it carries nutrients, electrolytes, waste products, and hormones.
Video by TheVisualMD
Red Blood Cell (RBC) Indices (Anemia Labs)
Video by Nursing School Explained/YouTube
WellnessFX: Red Blood Cell Indices Part 1 with Bryan Walsh
Video by WellnessFX/YouTube
WellnessFX: Red Blood Cell Indices Part 2 with Bryan Walsh
Video by WellnessFX/YouTube
Red Blood Cells Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing
Video by NURSINGcom/YouTube
This browser does not support the video element.
Flowing Red Blood Cell (RBC)
Animation of red blood cells flowoing quicly through a blood vessel. The camera is positioned in the lumen of the vessel and the rbc's are flowing towards the viewer. The rbc and and lumen are rendered with muted colors to give it a softer look.
Video by TheVisualMD
This browser does not support the video element.
Red Blood Cell Development
This video explains red blood cell development, following a pluripotent stem cell to red blood cell.
Video by TheVisualMD
Red blood cells
John Kalekos of Massachusetts image distribution for Science and Learning
Red Blood Cell
TheVisualMD
Red Blood Cell in Capillary
TheVisualMD
Blood Smear Showing Reduced Red Blood Cell Count
TheVisualMD
Red Blood Cell (RBC)
TheVisualMD
Red Blood Cell
TheVisualMD
Capillary Revealing Red Blood Cell
TheVisualMD
Red Blood Cell and White Blood Cell
TheVisualMD
Blood Smear Showing Normal Red Blood Cell Count
TheVisualMD
Tubule of Nephron Revealing Many Red Blood Cell
TheVisualMD
Red Blood Cell in Capillary
TheVisualMD
Tubule of Nephron Revealing Few Red Blood Cell
TheVisualMD
2:12
Complete Blood Count, and Baselining Your Health
TheVisualMD
7:45
Red Blood Cell (RBC) Indices (Anemia Labs)
Nursing School Explained/YouTube
33:35
WellnessFX: Red Blood Cell Indices Part 1 with Bryan Walsh
WellnessFX/YouTube
28:05
WellnessFX: Red Blood Cell Indices Part 2 with Bryan Walsh
WellnessFX/YouTube
3:01
Red Blood Cells Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing
NURSINGcom/YouTube
0:12
Flowing Red Blood Cell (RBC)
TheVisualMD
0:31
Red Blood Cell Development
TheVisualMD
RDW (Red Cell Distribution Width) Test
RDW (Red Cell Distribution Width) Test
Also called: Red Cell Distribution Width, RDW, RDW Blood Test, Erythrocyte Distribution Width, RBC Distribution Width
A red cell distribution width (RDW) test measures the size and volume of your red blood cells. RDW is usually part of a complete blood count (CBC) test. Measuring RDW can help diagnose anemia and other blood disorders.
RDW (Red Cell Distribution Width) Test
Also called: Red Cell Distribution Width, RDW, RDW Blood Test, Erythrocyte Distribution Width, RBC Distribution Width
A red cell distribution width (RDW) test measures the size and volume of your red blood cells. RDW is usually part of a complete blood count (CBC) test. Measuring RDW can help diagnose anemia and other blood disorders.
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Use the slider below to see how your results affect your
health.
%
11.5
14.5
Your result is Normal.
A normal RDW means that your red blood cells are similar in size. A normal result doesn’t mean that you don’t have a condition requiring treatment. Some types of anemia involve a normal RDW result but a high or low score on one of the other RBC indices.
Related conditions
A red cell distribution width (RDW) test measures the differences in the volume and size of your red blood cells (erythrocytes). Red blood cells carry oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, make new cells, and stay healthy.
Normally, your red blood cells are all about the same size. A high RDW means that there's a major difference between the size of your smallest and largest red blood cells. This may be a sign of a medical condition.
Other names: RDW-SD (standard deviation) test, Erythrocyte Distribution Width
The RDW blood test is often part of a complete blood count (CBC), a test that measures many different parts of your blood, including red cells. The RDW test is commonly used to help diagnose anemia, a condition in which your red blood cells can't carry enough oxygen to the rest of your body.
The RDW test may also be used with other tests to help diagnose other conditions, including thalassemia, an inherited disease that can cause severe anemia.
Your health care provider may have ordered a complete blood count, which includes an RDW test, as part of a routine exam, or if you have:
Symptoms of anemia, including weakness, dizziness, pale skin, and cold hands and feet
A family history of thalassemia, sickle cell anemia, or other inherited blood disorder
A chronic illness such as Crohn's disease, diabetes, or HIV/AIDS
A diet low in iron and other minerals
A long-term infection
Excessive blood loss from an injury or surgical procedure
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This process generally takes less than five minutes.
No special preparation is necessary.
There is very little risk to a blood test. You may experience slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
RDW results help your provider understand how much your red blood cells vary in size and volume. Even if your RDW results are normal, you may still have a medical condition that needs treatment. That's why your provider will usually look at your RDW results along with the results of other blood tests. The combined test results can show a more complete picture of your red blood cells to help diagnose a variety of conditions, including:
Iron deficiency
Different types of anemia
Thalassemia
Sickle cell anemia
A high RDW result can also be a sign of other conditions, such as:
Chronic liver disease
Heart disease
Diabetes
Kidney disease
Cancer, especially colorectal cancer
Your provider will most likely need more tests to confirm a diagnosis.
If your test results indicate you have a chronic blood disorder, such as anemia, you may be put on a treatment plan to increase the amount of oxygen that your red blood cells can carry. Depending on your specific condition, your provider may recommend iron supplements, medicines, and/or changes in your diet.
Be sure to talk to your provider before taking any supplements or making any changes in your eating plan.
RDW (Red Cell Distribution Width): MedlinePlus Medical Test [accessed on Jan 22, 2024]
Red Blood Cell Distribution Width (RDW): Definition and Calculation - LabCE.com, Laboratory Continuing Education [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (39)
Red Cell Distribution Width (RDW); What Does This Lab Test REALLY Mean?
Understanding the mean cell volume (MCV) - Full Blood Count Masterclass series
Video by Vernon Louw MedEd/YouTube
WellnessFX: Red Blood Cell Indices Part 2 with Bryan Walsh
Video by WellnessFX/YouTube
Red Blood Cells Carry Oxygen
This video focuses on one of the main components of blood, the red blood cell and its function to carry oxygen. The video begins with revealing the red blood cells and the heart that pumps the oxygenated blood to the rest of the body. Hemoglobin is the protein molecule found in these red blood cells that enable blood to transport oxygen. If the blood's capacity to transport oxygen to the tissues is reduced due to a decrease in the number of red blood cells, anemia may occur.
Image by TheVisualMD
Red Blood Cell Development
This video explains red blood cell development, following a pluripotent stem cell to red blood cell.
Image by TheVisualMD
Red Blood Cell Production
Red blood cell production or erythropoiesis is the process by which red blood cells are formed.
Image by TheVisualMD
What To Expect Before a Blood and Marrow Stem Cell Transplant
Georgetown University Hospital, Washington, D.C. (Dec. 4, 2002) - Surgical technician Amina Sherali places recently transfused bone marrow from Aviation Electronics Technician 1st Class Michael Griffioen into a sterile bag in preparation for transplant. To determine the amount of marrow needed from each donor, a sample is taken during the operation and T-cells are counted. The level of T-cells and the body size of the recipient determine the amount of bone marrow to be harvested. Griffioen is assigned to Precommissioning Unit Ronald Reagan and was matched with an anonymous cancer patient through the Department of Defense Marrow Donor Program. Griffioen chose to donate his bone marrow after participating in a donor drive nine years ago while stationed aboard USS George Washington.
Image by U.S. Navy photo by Photographer's Mate 2nd Class Chad McNeeley.
Bone structure
Anatomy of the bone. The bone is made up of compact bone, spongy bone, and bone marrow. Compact bone makes up the outer layer of the bone. Spongy bone is found mostly at the ends of bones and contains red marrow. Bone marrow is found in the center of most bones and has many blood vessels. There are two types of bone marrow: red and yellow. Red marrow contains blood stem cells that can become red blood cells, white blood cells, or platelets. Yellow marrow is made mostly of fat.
Image by Smart Servier website
Hematopoiesis
The Hematopoietic System of the Bone Marrow
Image by OpenStax College
Hemoglobin: Hemoglobin in Red Blood Cells
Hemoglobin is a complex, iron-containing protein molecule found in red blood cells; it is the iron in this molecule that makes red blood cells red. Hemoglobin enables red blood cells to carry oxygen from the lungs to all cells of the body.
Image by TheVisualMD
Red Blood Cells, Blood Smear
Individual blood cells were first detected and described in 17th century. Later, red blood cells were counted manually from a blood smear, a thin film of blood prepared on a glass slide and examined under a microscope. Blood analysis is now automated, though blood smears are still used to detect visible abnormalities. There are normally between 4.2-5.8 million red blood cells per microliter (about a drop), which means there are 20-30 trillion red blood cells circulating through the body of an adult.
Image by TheVisualMD
Blood and Blood Components
Like bone and cartilage, blood can be seen as a connective tissue, a mass of cells embedded in a framework. However, because its job is mobile, not fixed, its matrix is a liquid - plasma. Suspended in plasma are trillions of blood cells. Dimpled, disk-shaped red blood cells, built to provide a large surface in relation to volume, transport oxygen to tissues. Granular, many-lobed white blood cells, outnumbered by about 700 to 1, comprise a mobile defense force. Platelets, designed to aid in tissue repair, are tiny round or oval cell fragments that congregate around damaged sites in the bloodstream, swelling and sticking to each other to from temporary pugs that can stop leaks.
Image by TheVisualMD
Red Blood Cell
The RBC is disc-shaped and concave on both sides. The concave shape increases the cells' surface area, which allows them to distribute more oxygen to the body's cells. The shape also enables the cells to bunch together more compactly, helping them travel through the bloodstream more efficiently. Some RBCs are a bit thicker or thinner, wider or longer than others, but can change their shape to suit the demands of their environment. The cell membranes of the RBCs are protein meshes that give them flexibility, allowing them to navigate the twists and turns of the blood vessel network. The nearly 300 million hemoglobin molecules contained within each RBC easily move and slide past each other within the cell, adjusting their positions to conform to the RBC's shifting shape. Diameter : 7 μm
Image by TheVisualMD
Red Blood Cells Delivering Oxygen
Red blood cells deliver oxygen from the lungs to cells throughout the body and carry carbon dioxide from these cells back to the lungs. This continuous exchange is accomplished through a vast network of arteries, veins and vessels that would extend 60,000 miles if stretched end-to-end, enough to circle the globe 3-4 times. All but a tiny fraction of this vessel network is invisible to the naked eye. The smallest capillaries (from the Latin for \"hairlike\") are so narrow that red blood cells must pass through in single file.
Image by TheVisualMD
Red Blood Cell Revealing Cell Membrane
The RBC is disc-shaped and concave on both sides. The concave shape increases the cells' surface area, which allows them to distribute more oxygen to the body's cells. The shape also enables the cells to bunch together more compactly, helping them travel through the bloodstream more efficiently. The cell membrane of this RBC comes into view on the right side. The membrane is made up of protein meshes that gives the RBC flexibility, allowing it to navigate the twists and turns of the blood vessel network.
Image by TheVisualMD
Tubule of Nephron Revealing Few Red Blood Cell
Our kidneys are remarkable filters. Each day, they filter about 200 quarts of blood to extract about 2 quarts of wastes, which is then eliminated as urine. The kidneys' delicate filtration units are called nephrons; each kidney has about a million nephrons, and within each nephron are dense forests of tiny capillaries called glomeruli, which remove waste products from the blood while preventing the loss of other components, including proteins, electrolytes and blood cells. The glomerular filtration rate is the amount of blood that is filtered by the glomeruli per minute.
Image by TheVisualMD
Red Blood Cell
This image shows two red blood cells. The red blood cell is also called an erythrocyte: erythro is Greek for \"red,\" cyte is Latin for \"cell.\" The disc-shaped RBCs have the critical job of transporting oxygen from the lungs to the body's cells and bringing carbon dioxide from the cells back to the lungs to be expelled.
Image by TheVisualMD
Hemoglobin: Red Blood Cells
There are 20 to 30 trillion red blood cells circulating through the body of an adult. Individual red blood cells live about 100 days, which means that about 2 million die (and an equal number replaced) every second.
Image by TheVisualMD
Red Blood Cell Indices: Blood Component
Blood comprises of 55% plasma, 1% platelets and white blood cells, and 45% red blood cells.
Image by TheVisualMD
Bilirubin, Direct: Red Blood Cells
There are 20 to 30 trillion red blood cells circulating through the body of an adult. Individual red blood cells live about 100 days, which means that about 2 million die (and an equal number replaced) every second. Bilirubin is left behind after these older blood cells are removed.
Image by TheVisualMD
red blood cells
Illustration of red blood cells
Image by Jessica Polka
Thalassemic Red Blood Cell
This image shows red blood cells that are consistent with the anemia disorder thalassemia. They are less red and smaller than normal red blood cells.
Image by TheVisualMD
Iron Deficient Red Blood Cells
Anemia occurs when there are too few red blood cells in the bloodstream to deliver adequate oxygen to body tissues. There are different types and causes of anemia, but iron deficiency is the most common. Different tests can determine the amount of iron in the blood, the capacity of the blood to transport iron, and the amount of iron in storage. Iron is transported throughout the body with the help of proteins. The total iron binding capacity test (TIBC) measures the blood's ability to bind and transport iron
Image by TheVisualMD
White Blood Cell and Red Blood Cell
Medical visualization of blood cells. Depicted are numerous red blood cells and a single white blood cell.
Image by TheVisualMD
Blood Smear Showing Reduced Red Blood Cell Count
Individual blood cells were first detected and described in the 17th century. Later, red blood cells (RBCs) were counted manually from a blood smear, a thin film of blood prepared on a glass slide and examined under a microscope (blood analysis is now automated, though smears are still used to detect visible abnormalities and to check or confirm the results of other tests). Anemia results when there are too few RBCs in circulation because they are being destroyed too quickly or produced too slowly. Anemia can be temporary or long term and range from mild to severe. Folate (also known as vitamin B9) is necessary for red blood cell production and the prevention of anemia, as well as the metabolism of carbohydrates. But folate also plays key roles in the synthesis and maintenance of DNA and is especially important in cell division and growth in fetal development (deficiencies of the vitamin in pregnancy is a common cause of birth defects). Pernicious anemia is a disorder in which the body's loses its ability to utilize folate and vitamin B12.
Image by TheVisualMD
Red Blood Cell in Capillary
The cardiovascular system is vast network of arteries, veins and vessels that would extend 60,000 miles if stretched end-to-end. All but a tiny fraction of this vessel network is invisible to the naked eye. The smallest capillaries (from latin "hairlike") are so narrow that red blood cells must pass through in single file. Higher than normal blood iron levels have been linked to heart disease and the reason is believed to be the oxidative stress the excess iron places on the walls of the blood vessels. It is the biological counterpart of rust. There are 20-30 trillion red blood cells (RBCs) in an adult's body. The life span of RBCs, which are produced in bone marrow, is about 100 days, which means that 2 million die (and are replaced) each second, but in that short lifetime they can make 75,000 round trips between lungs, heart and tissues in the body.
Image by TheVisualMD
Kidney and Stem Cell Creating Red Blood Cell. B12 is critical for the creation of red blood cells.
We are used to thinking of our kidneys mostly as hardworking filters that rid our bodies of wastes and excess water. But the kidneys are also constantly monitoring and adjusting levels of key substances in the blood, depending on what the body needs. Specialized cells in the kidney that are very sensitive to low oxygen levels, for example, produce a hormone called erythropoietin (EPO), which in turn promotes the production of red blood cells in the bone marrow. The boost in red blood cells increases the oxygen-carrying capacity of the blood.
Image by TheVisualMD
Arteries and Veins
The body's blood vessels, consisting of arteries, veins, and capillaries, range in size from arteries as wide as a garden hose to capillaries so thin that it would take 10 of them, lined up side by side, to form the thickness of a human hair. But they all have one thing in common: they are designed to move blood as quickly and efficiently as possible. That means they need to be strong, flexible, and smooth. Even the components of your blood, like red blood cells, platelets, and white blood cells, are designed for movement. Red blood cells can actually flex so that they are able to flow through the finest of capillaries. The high levels of glucose characteristic of diabetes damage both large and small blood vessels. Too much glucose acts as a toxin to the lining of the blood vessels and injures both large vessels (arteries) and small vessels (capillaries). Damage to blood vessels is something that all the main complications of diabetes have in common. Many cells in the body, such as those of the skeletal muscles and liver, require insulin to admit glucose. This isn't true of the cells that line blood vessels, called endothelial cells. They can't restrict their glucose intake. When levels of blood glucose are very high, these cells develop high glucose levels as well. The high glucose levels start a whole chain of events inside the cells that damages them in numerous ways. About three quarters of people with diabetes die of cardiovascular disease-diseases of the heart and blood vessels.
Image by TheVisualMD
Red Blood Cells
Digital holographic microscopy (DHM) image of red blood cells.
Image by Egelberg (talk)
Red Blood Cell in Capillary
Red blood cells in capillaries carry oxygen to muscle and other tissues.
Image by TheVisualMD
Red Blood Cell Traveling Through Capillary
Red blood cells travel through a capillary, the smallest blood vessel in the body.
Image by TheVisualMD
Oxygenated vs deoxygenated Red Blood Cells (RBC)
A comparison between human red blood cells differing in oxygenation state. The cell on the left presents an oxygenated appearance as it would while in arterial circulation (after loading oxygen and unloading carbon dioxide in the lungs). The cell on the right appears as it would when deoxygenated, or in venous circulation (after unloading oxygen and loading carbon dioxide in the oxygen requiring-tissue capillaries).
Image by Rogeriopfm
Life Cycle of Red Blood Cell
We have a total of 20 to 30 trillion RBCs in the body and to maintain the body's healthy equilibrium, about 2.5 million RBCs are destroyed and replaced every second. In early development, RBC production begins in the yolk sac, shifts to the liver and spleen during the 3rd month of gestation, and finally to the bone marrow in the 5th month. Once adulthood is reached, the creation of RBCs is mostly restricted to the marrow from the ends of the \"long\" bones-the vertebrae, ribs, and pelvis-with a little produced in the skull. The life cycle of a normal RBC is about 120 days, just four months. But in that short lifetime the RBC makes an astonishing 75,000 round trips between the lungs, heart and cells of the body. Since RBCs do not possess a nucleus, they are unable to repair or synthesize new cellular components and eventually they wear out. When that happens, most aging RBCs are pulled out of circulation by specialized white blood cells called macrophages within the liver, spleen, and lymph nodes. The macrophages engulf RBCs, \"digest\" them and release some of their components to be recycled within the body. As old RBCs are broken down and their components re-utilized, the bone marrow is constantly at work producing new RBCs. In a healthy human being, this is a dynamic and continuous process.
Image by TheVisualMD
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Red Blood Cells
Diagram of a red blood cell
Image by Cancer Research UK uploader
Red Blood Cells
Figure shows normal red blood cells flowing freely in a blood vessel. The inset image shows a cross-section of a normal red blood cell with normal hemoglobin.
Image by NHLBI
5:54
Red Cell Distribution Width (RDW); What Does This Lab Test REALLY Mean?
Understanding the mean cell volume (MCV) - Full Blood Count Masterclass series
Vernon Louw MedEd/YouTube
28:05
WellnessFX: Red Blood Cell Indices Part 2 with Bryan Walsh
WellnessFX/YouTube
Red Blood Cells Carry Oxygen
TheVisualMD
Red Blood Cell Development
TheVisualMD
Red Blood Cell Production
TheVisualMD
What To Expect Before a Blood and Marrow Stem Cell Transplant
U.S. Navy photo by Photographer's Mate 2nd Class Chad McNeeley.
Bone structure
Smart Servier website
Hematopoiesis
OpenStax College
Hemoglobin: Hemoglobin in Red Blood Cells
TheVisualMD
Red Blood Cells, Blood Smear
TheVisualMD
Blood and Blood Components
TheVisualMD
Red Blood Cell
TheVisualMD
Red Blood Cells Delivering Oxygen
TheVisualMD
Red Blood Cell Revealing Cell Membrane
TheVisualMD
Tubule of Nephron Revealing Few Red Blood Cell
TheVisualMD
Red Blood Cell
TheVisualMD
Hemoglobin: Red Blood Cells
TheVisualMD
Red Blood Cell Indices: Blood Component
TheVisualMD
Bilirubin, Direct: Red Blood Cells
TheVisualMD
red blood cells
Jessica Polka
Thalassemic Red Blood Cell
TheVisualMD
Iron Deficient Red Blood Cells
TheVisualMD
White Blood Cell and Red Blood Cell
TheVisualMD
Blood Smear Showing Reduced Red Blood Cell Count
TheVisualMD
Red Blood Cell in Capillary
TheVisualMD
Kidney and Stem Cell Creating Red Blood Cell. B12 is critical for the creation of red blood cells.
TheVisualMD
Arteries and Veins
TheVisualMD
Red Blood Cells
Egelberg (talk)
Red Blood Cell in Capillary
TheVisualMD
Red Blood Cell Traveling Through Capillary
TheVisualMD
Oxygenated vs deoxygenated Red Blood Cells (RBC)
Rogeriopfm
Life Cycle of Red Blood Cell
TheVisualMD
Sensitive content
This media may include sensitive content
Red Blood Cells
Cancer Research UK uploader
Red Blood Cells
NHLBI
Red Blood Cell (RBC) Morphology Test
Red Blood Cell (RBC) Morphology Test
Also called: RBC-M, Red Cell Morphology, Red Blood Cell Morphology, RBC Morphology, Erythrocyte Morphology
A red blood cell (RBC) morphology is a test done to evaluate the size, shape, structure, and color of your red blood cells (erythrocytes). This test is useful to help detect and help diagnose a wide variety of blood disorders.
Red Blood Cell (RBC) Morphology Test
Also called: RBC-M, Red Cell Morphology, Red Blood Cell Morphology, RBC Morphology, Erythrocyte Morphology
A red blood cell (RBC) morphology is a test done to evaluate the size, shape, structure, and color of your red blood cells (erythrocytes). This test is useful to help detect and help diagnose a wide variety of blood disorders.
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Use the slider below to see how your results affect your
health.
Your result is Normal.
A normal result shows that your RBCs are of average shape, size, and color. This is usually reported as “normocytic” (normal size) and “normochromic” (normal color).
Related conditions
Red blood cell (RBC) morphology evaluates the shape, size, color, inclusions, and arrangement of your red blood cells. Red blood cells, also known as erythrocytes, carry oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, reproduce, and stay healthy.
Deviations from the normal in terms of size, shape, color, distribution or presence of inclusion bodies suggests possible disease processes. Any imbalances affecting production or destruction of red cells result in red cell disorder.
Abnormalities of RBC shape and other RBC features can provide key information in establishing a differential diagnosis. A differential diagnosis process is used to help make a final diagnosis when you have symptoms that don't have one clear cause.
RBC morphology can help to differentiate between different types of blood disorders, and, specifically, to:
increase or decrease the diagnostic likelihood of thalassemia
differentiate between blood loss, marrow failure, and hemolysis
guide the diagnostic considerations for the different types of anemia
An RBC morphology evaluation is typically done on a blood smear. You may need a blood smear if you have abnormal results on a complete blood count (CBC). A CBC is a routine test that measures many different parts of your blood.
Your health care provider may order a blood smear if you have symptoms of a blood disorder, such as:
Fatigue
Jaundice, a condition that causes your skin and eyes to turn yellow
Unusual bleeding, including nosebleeds
Fever that lasts, or comes and goes
Bone pain
Anemia
Easy bruising
A spleen that's larger than normal
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
You don't need any special preparation for a blood smear. If your provider has ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test. Your provider will let you know if there are any special instructions to follow.
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
Normal
A normal result shows that your RBCs are of average shape, size, and color. This is usually reported as “normocytic” (normal size) and “normochromic” (normal color).
RBCs are donut-shaped with a light-colored depression in the middle instead of a hole (are biconcave) and have a pink to red color.
Abnormal
If a significant number of RBCs are abnormal in either shape, size, structure, and/or color; this means that a disease or condition that affects the RBCs is present.
A red blood cell abnormality can be indicative of a wide variety of conditions, such as:
Iron deficiency anemia
Megaloblastic anemia (due to folate or vitamin B12 deficiency)
Hemolytic anemia (RBC destruction)
Thalassemia
Hemoglobinopathies
Liver diseases
Alcoholism
Hypersplenism (overactive spleen).
Kidney failure
Leukemia (a type of cancer)
Bone marrow disorders
RBC morphology should not be used as a stand-alone test. Your doctor will take into consideration this test result, along with the results of other tests, your clinical findings, and your family medical history to reach an accurate diagnosis.
https://medlineplus.gov/ency/article/003665.htm [accessed on Mar 27, 2019]
https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=167&ContentID=blood_smear [accessed on Mar 27, 2019]
http://www.labpedia.net/test/127 [accessed on Mar 27, 2019]
https://www.mayocliniclabs.com/test-catalog/Clinical+and+Interpretive/9184 [accessed on Mar 27, 2019]
https://labtestsonline.org/tests/blood-smear [accessed on Mar 27, 2019]
https://www.ncbi.nlm.nih.gov/pubmed/23480230 [accessed on Mar 27, 2019]
https://laboratoryinfo.com/variations-in-red-blood-cell-morphology/ [accessed on Mar 27, 2019]
Interpretation of Red Blood Cell Morphology (Advanced Level) - WSAVA2004 - VIN [accessed on Jan 22, 2024]
Author. Blood Morphology - Ask Hematologist | Understand Hematology. Apr 30, 2018 [accessed on Jan 22, 2024]
Ann Abiola Ogbenna. Erythrocyte Morphology and Its Disorders. IntechOpen. Jun 14, 2019. doi:10.5772/intechopen.86112 [accessed on Jan 22, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
A platelet count test measures the number of platelets in your blood. Platelets, also known as thrombocytes, are small blood cells that are essential for blood clotting. Platelets may be counted to monitor or diagnose diseases, or to look for the cause of too much bleeding or clotting.
A platelet count test measures the number of platelets in your blood. Platelets, also known as thrombocytes, are small blood cells that are essential for blood clotting. Platelets may be counted to monitor or diagnose diseases, or to look for the cause of too much bleeding or clotting.
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Use the slider below to see how your results affect your
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10³/μL
50
150
450
Your result is Normal.
A normal platelet count ranges from 150,000 to 450,000 platelets per microliter of blood. Platelets are tiny blood cells that are made in the bone marrow from larger cells. When you are injured, platelets stick together to form a plug to seal your wound. This plug is called a blood clot.
Related conditions
Platelets, also known as thrombocytes, are small blood cells that are essential for blood clotting. Clotting is the process that helps you stop bleeding after an injury. There are two types of platelet tests: a platelet count test and platelet function tests.
A platelet count test measures the number of platelets in your blood. A lower than normal platelet count is called thrombocytopenia. This condition can cause you to bleed too much after a cut or other injury that causes bleeding. A higher than normal platelet count is called thrombocytosis. This can make your blood clot more than you need it to. Blood clots can be dangerous because they can block blood flow.
Other names: platelet count, thrombocyte count
A platelet count is most often used to monitor or diagnose conditions that cause too much bleeding or too much clotting. A platelet count may be included in a complete blood count, a test that is often done as part of a regular checkup.
You may need platelet count testing if you have symptoms of having too few or too many platelets.
Symptoms of too few platelets include:
Prolonged bleeding after a minor cut or injury
Nosebleeds
Unexplained bruising
Pinpoint sized red spots on the skin, known as petechiae
Purplish spots on the skin, known as purpura. These may be caused by bleeding under the skin.
Heavy and/or prolonged menstrual periods
Symptoms of too many platelets include:
Numbness of hands and feet
Headache
Dizziness
Weakness
Most platelet tests are done on a blood sample.
During the test, a health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
You don't need any special preparations for a platelet count test.
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
If your results show a lower than normal platelet count (thrombocytopenia), it may indicate:
A cancer that affects the blood, such as leukemia or lymphoma
A viral infection, such as mononucleosis, hepatitis, or measles
An autoimmune disease. This is a disorder that causes the body to attack its own healthy tissues, which can include platelets.
Infection or damage to the bone marrow
Cirrhosis
Vitamin B12 deficiency
Gestational thrombocytopenia, a common, but mild, low-platelet condition affecting pregnant women. It is not known to cause any harm to a mother or her unborn baby. It usually gets better on its own during pregnancy or after birth.
If your results show a higher than normal platelet count (thrombocytosis), it may indicate:
Certain types of cancer, such as lung cancer or breast cancer
Anemia
Inflammatory bowel disease
Rheumatoid arthritis
A viral or bacterial infection
Platelet Tests: MedlinePlus Medical Test [accessed on Jan 20, 2024]
Platelet Count (PLT) Blood Test - Testing.com. Dec 19, 2023 [accessed on Jan 20, 2024]
Platelet count: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
Normal reference ranges can vary depending on the laboratory and the method used for testing. You must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."
Additional Materials (8)
Platelet Development
Illustration of Platelet Development
Image by OpenStax College
Sensitive content
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Platelet Disorders
From left to right: erythrocyte, thrombocyte, leukocyte
Image by Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)
Scheme of a blood sample after centrifugation
scheme of a blood sample after centrifugation
Image by KnuteKnudsen (talk)
Decode Your Blood Test: Platelets 💉 | Merck Manual Consumer Version
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Complete Blood Count, and Baselining Your Health
Video Topics : Our lifeblood consists of many components and a complete blood count (CBC) includes measurements of the fundamental elements. The largest categories are red and white blood cells (RBCs and WBCs) and cell fragments called platelets, which play roles in blood clotting. There are 20-30 trillion red blood cells in the body of an adult, each with a lifespan of about 100 days (RBCs contain an iron-containing protein called hemoglobin that enables them to carry oxygen to tissues throughout the body and then return carbon dioxide to the lungs). WBCs are in the front lines in the body's ongoing fight against harmful viruses, bacteria and even fungus; when a pathogen enters the body, WBCs mobilize in a coordinated defense response to eliminate, neutralize or mark the invader for destruction. The liquid portion of blood is called plasma and it carries nutrients, electrolytes, waste products, and hormones.
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Platelets Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing
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Platelets Explained in Two Minutes
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The life and times of RBCs and platelets
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Platelet Development
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Platelet Disorders
Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)
Scheme of a blood sample after centrifugation
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Decode Your Blood Test: Platelets 💉 | Merck Manual Consumer Version
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Complete Blood Count, and Baselining Your Health
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Platelets Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing
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Platelets Explained in Two Minutes
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The life and times of RBCs and platelets
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Treatment
NECT treatment
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NECT treatment
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Chagas Disease - Treatment
Treatment for Chagas disease is recommended for people diagnosed early in the course of infection (acute phase), babies with congenital infection, and for those with suppressed immune systems. Many patients with chronic infection may also benefit from treatment.
Patients should consult with their primary health-care provider. Some patients may be referred to a specialist, such as a cardiologist, gastroenterologist, or infectious disease specialist.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (2)
NECT treatment
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KILLER DISEASES | Treating Chagas
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NECT treatment
Neil Brandvold-DNDi/Wikimedia
3:24
KILLER DISEASES | Treating Chagas
Médecins Sans Frontières/Doctors Without Borders/YouTube
Prevention
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Bungalow at Bird of Paradise
Interior of a bungalow at Bird of Paradise Bungalows, Kep, Cambodia.
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Chagas Disease - Prevention & Control
In areas of Mexico, Central America, and South America, where the Trypanosoma cruzi parasite is present in triatomine bugs, improved housing and spraying insecticide inside housing to eliminate the bugs has significantly decreased the spread of Chagas disease. Screening of blood donations for Chagas is another important public health tool to help prevent spreading the disease through blood transfusions. Early detection and treatment of new cases, including mother-to-baby (congenital) cases, will also help reduce the burden of disease.
In the United States and in other regions where Chagas disease is now found but is not widespread, control strategies are focused on preventing transmission from blood transfusion, organ transplantation, and mother-to-baby.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (2)
Blood transfusion
Blood bag with chamber dripping blood quickly
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KILLER DISEASES | Chagas in the Future
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Blood transfusion
Ian Furst/User:Doc James
2:28
KILLER DISEASES | Chagas in the Future
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Travelers' Health
DEET
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DEET
This image depicts a mother in the process of correctly applying mosquito repellant spray to her daughter’s right forearm. When spending long periods of time outdoors, reapply insect repellent according to product label instructions. In 2014, the first locally acquired case of chikungunya, a mosquito-borne disease, was reported July 17, in Florida. This case represented the first time that mosquitoes in the continental United States were thought to have spread the virus to a non-traveler.The best way to protect yourself and your family from chikungunya, as well as other mosquito-borne illnesses, including Zika virus, is to prevent being bitten by mosquitoes, by using insect repellent, wearing long sleeves and pants, using air conditioning or window/door screens to keep mosquitoes outside, and reducing mosquito breeding grounds, especially standing water.
What is Chagas Disease (American Trypanosomiasis)?
American trypanosomiasis, also known as Chagas disease, is caused by a parasite. This parasite lives in the feces (poop) of triatomine (kissing) bugs. The bug often poops when it bites. Most people get Chagas disease by unknowingly rubbing triatomine bug poop into the bug bite, for example, when they scratch the bite. People may also accidentally get triatomine bug poop in their eyes and mouth.
A few people experience swelling around the bite area. However, most people never have symptoms, but remain infected throughout their lives.
About 1 out of 3 people who get Chagas disease will develop more serious symptoms later in life, including heart conditions or gastrointestinal problems. These later symptoms can occur whether a person has early symptoms or not.
Who is at risk?
Chagas disease is spread by triatomine bugs in parts of Mexico, Central America, and South America, especially rural areas.
Most travelers to these areas don’t need to worry about Chagas disease. Travelers who sleep outdoors or stay in poorly constructed housing are more likely to get bitten by triatomine bugs.
What can travelers do to prevent Chagas disease?
There is no vaccine or medicine to prevent Chagas disease. Travelers can protect themselves by taking a few steps.
Avoid Bug Bites
Stay and sleep in screened or air-conditioned rooms.
Avoid sleeping in thatch, mud, and adobe housing in areas with triatomine bugs; use insecticides in and around such homes. Insecticide-treated bed nets are helpful
Cover exposed skin by wearing long-sleeved shirts, long pants, and hats.
Use EPA-registered insect repellents with one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. Find an EPA-registered insect repellent that’s right for you.
Always follow product directions and reapply as directed.
If you are also using sunscreen, apply sunscreen first and insect repellent second.
When using insect repellent on children
Do not use products containing oil of lemon eucalyptus (OLE) or para-menthane-diol (PMD) on children under 3 years old.
Do not apply insect repellent to a child’s hands, eyes, mouth, cuts, or irritated skin.
Adults: Spray insect repellent onto your hands and then apply to a child’s face.
Use permethrin-treated clothing and gear (such as boots, pants, socks, and tents). You can buy pre-treated clothing and gear or treat them yourself:
Treated clothing remains protective after multiple washings. See the product information to find out how long the protection will last.
If treating items yourself, follow the product instructions carefully.
Do not use permethrin directly on skin.
If you traveled and feel sick, particularly if you have a fever, talk to a healthcare provider, and tell them about your travel. Avoid contact with other people while you are sick.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (5)
Mosquito Control
This image depicts a woman who was seated outdoors at a recreational picnic table, while she was applying a spray of insect repellant to her legs. When spending long periods of time outdoors, reapply insect repellent according to product label instructions. To double protect yourself against a mosquito’s bite, wear long sleeves during peak mosquito biting hours, and spray DEET (diethyltoluamide) repellent directly onto your clothes. Don't apply repellents containing permethrin directly to skin, or spray repellent containing DEET on the skin under your clothing.
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DEET Products
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Pesticides
A new group of pesticides safer for humans—DEET, DDT, rotenone, and allethrin—help keep soldiers safe from insects and the diseases they spread. To this day, ARS continues to work with the U.S. military to solve problems.
Image by USDA Agricultural Research Service/Photo by Scott Bauer.
Applying insect repellent
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Care Plus DEET
A picture of the anti-mosquito lotion "Care Plus Deet". This lotion is based on diethyl-meta-toluamide (DEET). Other good repellents based on DEET are Off and Autan.
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Mosquito Control
CDC
DEET Products
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Pesticides
USDA Agricultural Research Service/Photo by Scott Bauer.
Applying insect repellent
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Care Plus DEET
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FAQs
Panstrongylus megistus on wood
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Panstrongylus megistus on wood
Panstrongylus megistus, a species of triatomine (kissing bug). Image modified by uploader to tighten cropping and remove a watermark.
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Chagas Disease
What is Chagas disease?
Chagas disease, or American trypanosomiasis, is an illness that can cause serious heart and stomach problems. It is caused by a parasite. Chagas disease is common in Latin America, especially in poor, rural areas. It can also be found in the United States, most often in people who were infected before they moved to the U.S.
What causes Chagas disease?
Chagas disease is caused by the Trypanosoma cruzi parasite. It is usually spread by infected blood-sucking bugs called triatomine bugs. They are also known as "kissing bugs" because they often bite people's faces. When of these bugs bites you, it leaves behind infected waste. You can become infected if you rub the waste in your eyes or nose, the bite wound, or a cut.
Chagas disease can also spread through contaminated food, a blood transfusion, a donated organ, or from mother to baby during pregnancy.
Who is at risk for Chagas disease?
Kissing bugs can be found throughout the Americas, but they are more common in certain areas. The people who are most at risk for Chagas disease
Live in rural areas of Latin America
Have seen the bugs, especially in those areas
Have stayed in a house with a thatched roof or with walls that have cracks or crevices
What are the symptoms of Chagas disease?
In the beginning, there may be no symptoms. Some people do get mild symptoms, such as
Fever
Fatigue
Body aches
Headache
Loss of appetite
Diarrhea
Vomiting
A rash
A swollen eyelid
These early symptoms usually go away. However, if you don't treat the infection, it stays in your body. Later, it can cause serious intestinal and heart problems such as
An irregular heartbeat that can cause sudden death
An enlarged heart that doesn't pump blood well
Problems with digestion and bowel movements
An increased chance of having a stroke
How is Chagas disease diagnosed?
A physical exam and blood tests can diagnose it. You may also need tests to see whether the disease has affected your intestines and heart.
What are the treatments for Chagas disease?
Medicines can kill the parasite, especially early on. You can also treat related problems. For example, a pacemaker helps with some heart complications.
Can Chagas disease be prevented?
There are no vaccines or medicines to prevent Chagas disease. If you travel to areas where it occurs, you are at higher risk if you sleep outdoors or are staying in poor housing conditions. It is important to use insecticides to prevent bites and practice food safety.
Source: Centers for Disease Control and Prevention / MedlinePlus
Heart pathology Chagas disease : Large scale anatomy of a heart that has been damaged by chronic Chagas disease
Image by CDC
Chagas Disease - Detailed FAQs
What is Chagas disease?
Chagas disease is caused by the parasite Trypanosoma cruzi, which is transmitted to animals and people by insect vectors that are found only in the Americas (mainly, in rural areas of Latin America where poverty is widespread). Chagas disease (T. cruzi infection) is also referred to as American trypanosomiasis.
It is estimated that as many as 8 million people in Mexico, Central America, and South America have Chagas disease, most of whom do not know they are infected. If untreated, infection is lifelong and can be life threatening.
The impact of Chagas disease is not limited to only rural areas of Latin America in which vectorborne transmission (diseases transmitted by insects) occurs. Large-scale population movements from rural to urban areas of Latin America and to other regions of the world have increased the geographic distribution and changed the epidemiology of Chagas disease. In the United States and in other regions where Chagas disease is now found but is not endemic, control strategies should focus on preventing transmission from blood transfusion, organ transplantation, and mother-to-baby (congenital transmission).
How do people get Chagas disease?
People can become infected in several ways. In areas where Chagas disease is common, the main way is through vectorborne transmission. The insect vectors are called triatomine bugs. These blood-sucking bugs get infected with T. cruzi by biting an infected animal or person. Once infected, the bugs pass the parasites in their feces. The bugs are found in houses made from materials such as mud, adobe, straw, and palm thatch. During the day, the bugs hide in crevices in the walls and roofs. During the night, when the inhabitants are sleeping, the bugs emerge. Because they tend to bite people’s faces, triatomine bugs are also known as “kissing bugs”. After they bite and ingest blood, they defecate (poop) on the person. The person can become infected if T. cruzi parasites in the bug feces enter the body through mucous membranes or breaks in the skin. The unsuspecting, sleeping person may accidentally scratch or rub the feces into the bite wound, eyes, or mouth.
People also can become infected through
Congenital transmission (from a pregnant woman to her baby);
Blood transfusions;
Organ transplantation;
Consumption of uncooked food that is contaminated with feces (poop) from infected triatomine bugs; and
Accidental laboratory exposure.
It is generally considered safe to breastfeed even if the mother has Chagas disease. However, if the mother has cracked nipples or blood in the breast milk, she should pump and discard the milk until the nipples heal and the bleeding resolves.
Chagas disease is not transmitted from person-to-person like a cold or the flu or through casual contact with infected people or animals.
If I have Chagas disease, should my family members be tested for the infection?
Possibly. They should be tested if they:
Could have become infected the same way that you did, for example, by vectorborne transmission;
Are your children and were born after you were infected; or if
There are other reasons to think that they might have Chagas disease.
In what parts of the world is Chagas disease found?
People who have Chagas disease can be found anywhere in the world. However, transmission of the disease by kissing bugs (vectorborne transmission), only occurs in the Americas. Most people with Chagas disease became infected in rural areas of Mexico, Central America, and South America. In some regions of Latin America, efforts to eliminate kissing bugs, called vector control programs, have succeeded in stopping this type of disease spread. Vectorborne transmission does not occur in the Caribbean (for example, in Puerto Rico or Cuba). Rare vectorborne cases of Chagas disease have been noted in the southern United States.
What are the signs and symptoms of Chagas disease?
Much of the clinical information about Chagas disease comes from experience with people who became infected as children through contact with triatomines. The severity and course of an individual infection can vary based on a number of factors, including the age at which a person became infected, the way in which a person acquired the infection, or the particular strain of the T. cruzi parasite.
There are two phases of Chagas disease: the acute phase and the chronic phase. Both phases can be symptom free or life threatening.
Romaña’s sign, the swelling of the child’s eyelid, is a marker of acute Chagas disease. Swelling is due to Trypanosoma cruzi infecting the eyelid when bug feces are accidentally rubbed into the eye, or because the bite wound was on the same side of the child’s face as the swelling. Credit: WHO/TDR
Acute phase: During this phase, which lasts for the first few weeks or months infection, a person may have no symptoms or mild ones, such as fever, fatigue, body aches, headache, rash, loss of appetite, diarrhea, and vomiting. Because these symptoms are similar to those of other illnesses, most people do not know their illness is from infection with the T. cruzi parasite.
However, a doctor may be able to pick up other signs of infection, including mild enlargement of the liver or spleen, swollen glands, or swelling at the site of the bite (called a chagoma), where the parasite entered the body. Some people with acute phase infection may have swelling of the eyelids on the side of the face near the bite wound or where the bug poop was accidentally rubbed into the eye, called Romaña’s sign. Even if a person develops symptoms during the acute phase, they usually feel well within a few weeks or months but if the person is not treated with antiparasitic medication, the infection remains in the body. Rarely, young children (less than 5%) die from severe inflammation and infection of the heart muscle (myocarditis) or brain (meningoencephalitis). The acute phase also can be severe in people with weakened immune systems, such as patients taking chemotherapy or those with advanced HIV infection.
Chronic phase: During this phase, which can last for decades or even for the entirety of someone’s lifetime, most people have no symptoms. Approximately 20–30 percent of infected people develop
Cardiac complications, which can include an enlarged heart, heart failure, altered heart rate or rhythm, and cardiac arrest (sudden death); and/or
Gastrointestinal complications, which can include an enlarged esophagus (megaesophagus) or colon (megacolon) and can lead to difficulties with eating or pooping.
What should I do if I think I have Chagas disease?
You should discuss your concerns with your health-care provider, who will examine you and ask you questions (for example, about your health and where you have lived). Chagas disease is diagnosed by blood tests. If you are found to have Chagas disease, you should have a heart tracing test (electrocardiogram), even if you feel fine. You might be referred to a specialist for more tests and for treatment.
How is Chagas disease treated?
Two approaches to therapy, that can be life-saving include:
Antiparasitic treatment, to kill the parasite; and
Symptomatic treatment, to manage the symptoms and signs of infection.
Antiparasitic treatment is most effective early in the course of infection but is not limited to cases in the acute phase. In the United States, there are two types of treatments available. Benznidazole is approved by FDA for use in children 2–12 years of age and is commercially available at http://www.benznidazoletablets.com/en/. Nifurtimox is not currently FDA approved and is available under an investigational protocol from CDC. Your health-care provider can talk with CDC staff about whether and how you should be treated. Most people do not need to be hospitalized during treatment.
Symptomatic treatment may help people who have cardiac or gastrointestinal problems from Chagas disease. For example, pacemakers and medications for irregular heartbeats may be life saving for some patients with chronic cardiac disease.
I plan to travel to a rural area of Latin America that might have Chagas disease. How can I protect myself from this infection?
No drugs or vaccines for preventing infection are currently available. Travelers who sleep indoors, in well-constructed facilities (for example, air-conditioned or screened hotel rooms), are at low risk for exposure to infected triatomine bugs that usually live in poor-quality dwellings and are most active at night. Preventive measures include spraying infested dwellings with long-lasting insecticides, using bed nets treated with long-lasting insecticides, wearing protective clothing, and applying insect repellent to exposed skin. Travelers should observe food and beverage precautions and avoid consuming salads, uncooked vegetables, unpeeled fruits, and unpasteurized fruit juices.
This information is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the parasites described above or think that you may have a parasitic infection, consult a health care provider.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (3)
Heart radiology Chagas disease
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Chagas disease. Awareness & prevention campaign poster. French Guiana 2008
Chagas disease, awareness and prevention campaign: poster on a wall in Cayenne, French Guiana, 2008
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KILLER DISEASES | Mapping Chagas
Video by Médecins Sans Frontières/Doctors Without Borders/YouTube
Heart radiology Chagas disease
/Wikimedia
Chagas disease. Awareness & prevention campaign poster. French Guiana 2008
Palp/Wikimedia
2:57
KILLER DISEASES | Mapping Chagas
Médecins Sans Frontières/Doctors Without Borders/YouTube
Blood Screening FAQs
Blood Smear
Image by CDC/Steven Glenn
Blood Smear
Example of properly prepared thick and thin film blood smears to be examined (Giemsa stain).
Image by CDC/Steven Glenn
Chagas Disease - Blood Screening FAQs
Why are blood banks screening for Trypanosoma cruzi infection, the parasite that causes Chagas disease?
The transmission of Trypanosoma cruzi through blood transfusion is a recognized risk. Screening tests have been approved by the U.S. Food and Drug Administration. Screening for Trypanosoma cruzi infection makes the blood supply even safer for everyone.
How does the screening test protect people from Chagas disease?
The blood screening test allows blood banks to destroy potentially infectious blood before it is given to anyone.
What happens to the blood that tests positive on the screening test?
The blood that tests positive will be removed from the blood supply.
Will I be tested automatically?
Yes. In the United States, donors are tested once and if the result of their test is negative for T. cruzi infection, they will not be tested when they donate again at that blood bank.
If my blood tests positive on the screening test, does that mean I have Chagas disease?
Probably. However, no test is perfect and occasionally a test can give a “false-positive” result. You should discuss your results with your health-care provider.
What does a “false-positive” result mean?
A “false-positive” result is when test results look like a person has a disease, but further testing indicates the person does not have the disease after all.
Will the blood bank let me know if my blood tests positive for T. cruzi infection?
Yes. The blood bank will contact you if you test positive for Trypanosoma cruzi infection and will provide general information about the disease.
Can I get Chagas disease from donating blood?
No. You cannot contract Chagas disease from donating blood. The needles are only used once and are discarded. Sterile procedures and equipment are routine at blood banks.
Can Chagas disease be spread through blood transfusions?
Yes. The disease can be spread by receiving blood that came from a person with Chagas disease.
If I test positive for T. cruzi infection, can I give blood again?
Maybe. You should contact the blood bank about possible retesting to see if you can donate blood again. In 2017, the U.S. Food and Drug Administration issued new rules about how donors who tested false positive can be evaluated to see if they are eligible to donate blood again. If you were diagnosed by your doctor, you cannot donate blood.
If I was diagnosed with Chagas disease in the past, can I donate blood?
No. If you have ever been diagnosed with Chagas disease, you cannot donate blood.
If I have had a transfusion or a transplant, should I be concerned about getting Chagas disease?
Probably not. The risk is very low. You should, however, be aware of the potential risk for Chagas disease infection and the need to monitor your health. If you have symptoms of Chagas disease or other concerns you should contact your health-care provider.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (1)
Chagas Disease: Breaking the Silence
Video by World Heart Federation/YouTube
3:53
Chagas Disease: Breaking the Silence
World Heart Federation/YouTube
Triatomine Bug FAQs
Trypanosoma cruzi life cycle
Image by Kárita C. F. Lidani, Lorena Bavia, Altair R. Ambrosio and Iara J. de Messias-Reason/Wikimedia
Trypanosoma cruzi life cycle
:The Complement System: A Prey of Trypanosoma cruzi FIGURE 1. Life cycle of Trypanosoma cruzi. Transmission is initiated by insect vectors that defecate after a blood meal and release metacyclic trypomastigotes near the bite wound. This infective stage is characterized by the invasion of host cells by trypomastigotes forming the parasitophorous vacuole, from which they subsequently escape, differentiate into amastigotes, and replicate in the cytosol. The amastigotes then divide, differentiate into trypomastigotes, and upon rupture of the cell spread the infection to tissues. Trypomastigotes reach the bloodstream, where they are eventually taken up by the insect vector or infect new cells. In the triatomine bugs, trypomastigotes differentiate into spheromastigotes becoming initially short epimastigotes (mid-log). After migration to the bug’s hindgut, elongate epimastigotes (late-log) attach to the waxy gut cuticle and give rise to infectious metacyclic trypomastigotes, completing the parasite life cycle.
Image by Kárita C. F. Lidani, Lorena Bavia, Altair R. Ambrosio and Iara J. de Messias-Reason/Wikimedia
Triatomine Bug FAQs
What is a triatomine bug and what does it look like?
Various triatomine bugs in all life stages, from eggs to nymphs to fully grown adults. A variety of bug species, that share similar traits, are pictured.
Triatomine bugs are a type of reduviid bug that can carry Trypanosoma cruzi, the parasite that causes Chagas disease.
Where are triatomine bugs typically found?
Triatomine bugs (also called “kissing bugs”, cone-nosed bugs, and blood suckers) can live indoors, in cracks and holes of substandard housing, or in a variety of outdoor settings including the following:
Beneath porches
Between rocky structures
Under cement
In rock, wood, brush piles, or beneath bark
In rodent nests or animal burrows
In outdoor dog houses or kennels
In chicken coops or houses
They are typically found in the southern United States, Mexico, Central America, and South America (as far south as southern Argentina). The map below details triatomine occurrence by U.S. state.
Eleven different species of triatomine bugs have been found in the southern United States:
Paratriatoma hirsuta
Triatoma gerstaeckeri
Triatoma incrassata
Triatoma indictiva
Triatoma lecticularia
Triatoma neotomae
Triatoma protracta
Triatoma recurva
Triatoma rubida
Triatoma rubrofasciata
Triatoma sanguisuga
Triatomines are mostly active at night and feed on the blood of mammals (including humans), birds, and reptiles. Triatomine bugs live in a wide range of environmental settings, generally within close proximity to an animal the bug can feed on, called a blood host. In areas of Latin America where human Chagas disease is an important public health problem, the bugs nest in cracks and holes of substandard housing.
Because most indoor structures in the United States are built with plastered walls and sealed entryways to prevent insect invasion, triatomine bugs rarely infest indoor areas of houses. Discovery of the earlier stages of the bug (wingless, smaller nymphs) inside can be a sign of a triatomine infestation. When the bugs are found inside, they are likely to be in one of the following settings:
Near the places your pets sleep
In areas of rodent infestation
In and around beds and bedrooms, especially under or near mattresses or night stands
How can I keep triatomine bugs away from my home?
Synthetic pyrethroid bug sprays have been used successfully in Latin America to get rid of house infestations. Although similar chemicals are available in the United States, none have been specifically approved for use against triatomine bugs. A licensed pest control operator should be consulted before using any insecticides to kill triatomine bugs. Roach hotels or other “bait” formulations do not work against triatomine bugs. Long lasting insecticide treated bednets and curtains have been shown to kill these bugs.
Other precautions to prevent house infestation include the following:
Sealing cracks and gaps around windows, walls, roofs, and doors
Removing wood, brush, and rock piles near your house
Using screens on doors and windows and repairing any holes or tears
If possible, making sure yard lights are not close to your house (lights can attract the bugs)
Sealing holes and cracks leading to the attic, crawl spaces below the house, and to the outside
Having pets sleep indoors, especially at night
Keeping your house and any outdoor pet resting areas clean, in addition to periodically checking both areas for the presence of bugs
I think I found a triatomine bug. What should I do?
If you find a bug you suspect is a triatomine, do not touch or squash it. Place a container on top of the bug, slide the bug inside, and fill it with rubbing alcohol or, if not available, freeze the bug in the container. Then, you may take it to your local extension service, health department, or a university laboratory for identification.
Surfaces that have come into contact with the bug should be cleaned with a solution made of 1 part bleach to 9 parts water (or 7 parts ethanol to 3 parts water).
Triatoma sanguisuga Credit: CDC, courtesy of James GathanyTriatoma gerstaeckeri next to a penny for scale. Credit: S. KjosTriatoma protracta Credit: CDC, courtesy of James Gathany
How can I tell if the bug I’ve found is a triatomine and not another kind of bug?
There are many beetles and non-triatomine reduviid bugs that resemble the triatomine bug. Two examples of non-triatomine reduviid bugs that do not feed on human blood, but prey upon other insects are the wheel bug and the western corsair. Some plant-feeding bugs, such as the leaf-footed bug also resemble the triatomine. If you are unsure if the bug you’ve found is a triatomine, you may wish to consult with an expert, such as an entomologist, for clarification.
More on: Bugs Commonly Confused with Triatomine Bugs
Can I get Trypanosoma cruzi, the parasite that causes Chagas disease, from a triatomine bug?
Yes. However, the transmission of the Trypanosoma cruzi parasite from a bug to a human is not easy. The parasite that causes the disease is in the bug feces. The bug generally poops on or near a person while it is feeding on her blood, usually when the person is sleeping. Transmission of the parasite happens when poop is accidentally rubbed into the bite wound or into a mucous membrane (for example, the eye or mouth), and the parasite enters the body.
It is important to note that not all triatomine bugs are infected with the parasite that causes Chagas disease. The likelihood of getting T cruzi infection from a triatomine bug in the United States is low, even if the bug is infected.
Could I be allergic to the bite of a triatomine bug?
Yes. The saliva of certain types of triatomines can cause an allergic reaction in some people. An allergic reaction can have severe redness, itching, swelling, welts, hives, or, rarely, anaphylactic shock (severe allergic reaction). People with a history of anaphylactic shock should consult a physician to obtain medication to use in case of a bite. It is important to note that not all triatomines are infected with the parasite even though their saliva may cause an allergic reaction.
An allergic reaction after a triatomine bite does not mean that you have been infected with the parasite T cruzi, the cause of Chagas disease. The swelling that may develop at the site of parasite inoculation (where the parasite entered the body through the skin or mucous membranes) is called a chagoma. When the parasite enters the body through the eye, the swelling around the eye is called Romaña’s sign. Chagomas, including Romaña’s sign, usually last longer than an allergic reaction and are less likely to be severely itchy.
What do I do if I think I may have Chagas disease?
If you suspect you have Chagas disease, consult your health-care provider. Or, to find a physician familiar with diagnosis and treatment of Chagas disease and other parasitic infections, ask your general practitioner or primary care physician for a referral. You may wish to consider visiting a physician who specializes in infectious diseases. To locate a clinician in your area, please visit the American Society of Tropical Medicine and Hygiene’s Clinical Consultants Directory.
Source: Centers for Disease Control and Prevention (CDC)
Additional Materials (2)
CDC Warns TN Of Kissing Bug, Chagas Disease
Video by NewsChannel 5/YouTube
Disease Vectors
The insect depicted here, in this dorsal view, was a species of Triatoma, or kissing bug, which as a vector, is able to transmit the protozoan pathogen, Trypanosoma cruzi, which causes the incurable illness known as Chagas disease.
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Chagas Disease
Chagas disease, also called American trypanosomiasis, is a potentially life-threatening illness caused by a parasite that is spread by "kissing bugs", mainly in continental Latin America. It can cause serious heart and gastrointestinal problems, and there are approximately 10,000 deaths every year. Learn about the signs and symptoms of Chagas disease.