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Von Willebrand Disease

Table of Contents

Von Willebrand Disease

VWD; Angiohemophilia; Vascular Pseudohemophilia; Von Willebrand Disorder; Von Willebrand's Factor Deficiency

Von Willebrand disease (VWD) is a bleeding disorder that slows the blood clotting process, causing prolonged bleeding after an injury. VWD is the most common bleeding disorder, found in up to 1% of the U.S. population. There are 3 major types of VWD: Type 1, Type 2, and Type 3. Learn more about this bleeding disorder and how it's managed.

Factors V and VII, Cutting of Skin

Image by TheVisualMD

About

Human blood clot formed

Image by Joanne Mitchell

Human blood clot formed

This is an image of a blood clot taken using an inverted fluorescent confocal microscope (Zeiss LSM710). 3D render of a human blood clot formed in vitro under flow. Blood clots are made up of blood cells called platelets and a protein called fibrin which adheres to platelets and forms long strands which eventually join together in the form of a mesh in order to limit blood loss from wound sites. The green fluorescent staining represents the blood platelets which form the initial ‘plug’ at the site of injury. The red fluorescent staining represents Dylight647 labelled fibrin which has polymerised and formed a mesh around the platelets to form a blood clot. This 3D image shows that the fibrin has surrounded and encased the platelet aggregates in certain areas to form dense clots which mimic the 'platelet plug'.

Image by Joanne Mitchell

What Is Von Willebrand Disease?

Von Willebrand disease (VWD) is a blood disorder in which the blood does not clot properly. Blood contains many proteins that help the blood clot when needed. One of these proteins is called von Willebrand factor (VWF). People with VWD either have a low level of VWF in their blood or the VWF protein doesn’t work the way it should.

Normally, when a person is injured and starts to bleed, the VWF in the blood attaches to small blood cells called platelets. This helps the platelets stick together, like glue, to form a clot at the site of injury and stop the bleeding. When a person has VWD, because the VWF doesn’t work the way it should, the clot might take longer to form or form incorrectly and bleeding might take longer to stop. This can lead to heavy, hard-to-stop bleeding. Although rare, the bleeding can be serious enough to damage joints or internal organs, or even be life-threatening.

Source: Centers for Disease Control and Prevention (CDC)

Additional Materials (12)

Learn About Von Willebrand Disease

Video by healtharticle24/YouTube

Kristin - Living Life to the Fullest Despite von Willebrand Disease (VWD)

Video by CSL Behring/YouTube

Jordan - Living with von Willebrand Disease (VWD)

Video by CSL Behring/YouTube

Scanning electron micrograph of a fragment of a fibrin clot in whole blood

Scanning electron micrograph of a fragment of a fibrin clot in whole blood

Image by Сергей Обыденный

Platelet rotation

Platelets (also known as thrombocytes - from the Greek for "clotting cell") are actually not full-fledged cells. They are produced by the fragmentation of giant bone marrow cells called megakaryocytes. Platelets contain proteins on their surface that allow them to clump together and adhere to damaged blood vessel walls at the site of injury (they can change their shape to facilitate this process). Platelets also secrete substances that help trigger the series of steps (called the coagulation cascade) necessary for effective clotting.

Image by TheVisualMD

Von Willebrand disease

Video by Diane Atwood/YouTube

Von Willebrand disease- causes, symptoms, diagnosis, treatment, pathology

Video by Osmosis/YouTube

What Schools Should Know: Having a Student With a Bleeding Disorder

Video by National Hemophilia Foundation/YouTube

Diagnosing von Willebrand Disease - The Balancing Act

Video by The Balancing Act/YouTube

What is von Willebrand Disease?

Video by National Hemophilia Foundation/YouTube

von Willebrand disease - Platelet adhesion and aggregation - MADE EASY

Video by Daily Med Ed/YouTube

Playing it Safe With Hemophilia

Video by Centers for Disease Control and Prevention (CDC)/YouTube

3:57

Learn About Von Willebrand Disease

healtharticle24/YouTube

3:32

Kristin - Living Life to the Fullest Despite von Willebrand Disease (VWD)

CSL Behring/YouTube

1:58

Jordan - Living with von Willebrand Disease (VWD)

CSL Behring/YouTube

Scanning electron micrograph of a fragment of a fibrin clot in whole blood

Сергей Обыденный

Platelet rotation

TheVisualMD

3:21

Von Willebrand disease

Diane Atwood/YouTube

9:20

Von Willebrand disease- causes, symptoms, diagnosis, treatment, pathology

Osmosis/YouTube

3:44

What Schools Should Know: Having a Student With a Bleeding Disorder

National Hemophilia Foundation/YouTube

8:07

Diagnosing von Willebrand Disease - The Balancing Act

The Balancing Act/YouTube

3:16

What is von Willebrand Disease?

National Hemophilia Foundation/YouTube

5:11

von Willebrand disease - Platelet adhesion and aggregation - MADE EASY

Daily Med Ed/YouTube

3:16

Playing it Safe With Hemophilia

Centers for Disease Control and Prevention (CDC)/YouTube

What Is vWD?

What Is Von Willebrand Disease?

Von Willebrand disease is a bleeding disorder that slows the blood clotting process, causing prolonged bleeding after an injury. People with this condition often experience easy bruising, long-lasting nosebleeds, and excessive bleeding or oozing following an injury, surgery, or dental work. Mild forms of von Willebrand disease may become apparent only when abnormal bleeding occurs following surgery or a serious injury. People with this condition who have menstrual periods typically have heavy or prolonged bleeding during menstruation (menorrhagia), and some may also experience reproductive tract bleeding during pregnancy and childbirth. In severe cases of von Willebrand disease, heavy bleeding occurs after minor trauma or even in the absence of injury (spontaneous bleeding). Symptoms of von Willebrand disease may change over time. Increased age, pregnancy, exercise, and stress may cause bleeding symptoms to become less frequent.

Von Willebrand disease is divided into three types. Type 1 has one subtype (1C), and type 2 is divided into four subtypes (2A, 2B, 2M, and 2N). Type 1 is the most common of the three types, accounting for 75 percent of affected individuals. Type 1 is typically mild, but some people are severely affected. Type 2 accounts for about 15 percent of cases. This type is usually of intermediate severity. Type 3 is the rarest form of the condition, accounting for about 5 percent of affected individuals, and is usually the most severe.

Another form of the disorder, acquired von Willebrand syndrome, is not caused by inherited gene variants (also called mutations). Acquired von Willebrand syndrome is typically seen in people with other disorders, such as diseases that affect bone marrow or immune cell function. This rare form of the condition is characterized by abnormal bleeding into the skin and other soft tissues, usually beginning in adulthood.

Source: MedlinePlus Genetics

What Are the Different Types?

What Are the Types of Von Willebrand Disease?

Type 1

This is the most common and mildest form of VWD, in which a person has lower-than-normal levels of VWF. A person with Type 1 VWD also might have low levels of factor VIII (8), another type of blood-clotting protein. About 85% of people treated for VWD have Type 1.

Type 2

With this type of VWD, although the body makes normal amounts of the VWF, the factor does not work the way it should. Type 2 is further broken down into four subtypes―2A, 2B, 2M, and 2N―depending on the specific problem with the person’s VWF. Because the treatment is different for each type, it’s important that a person know which subtype he or she has.

In Type 2A, the VWF is not the right size and doesn’t help the platelets attach together in order to form a clot.
In Type 2B, the VWF attaches to platelets at the wrong time (when there is no injury). The body removes the platelets attached to VWF, causing a reduced amount of both platelets and VWF in the blood when needed to form a clot.
In Type 2M, the VWF does not attach to the platelets as it should, which decreases the platelets’ ability to form a clot when an injury occurs.
In Type 2N, the VWF attaches to the platelets normally. However, the VWF does not attach to another protein, Factor VIII (8), which is also needed for blood to clot. This causes the body to remove the Factor VIII (8) protein.

Type 3

This is the most severe form of VWD, in which a person has very little or no VWF and low levels of factor VIII. This is the rarest type of VWD. Only 3% of people with VWD have Type 3.

Source: Centers for Disease Control and Prevention (CDC)

Is It Common?

How Common Is Von Willebrand Disease?

Von Willebrand disease is estimated to affect 1 in 100 to 10,000 individuals. Because people with mild signs and symptoms are not likely to seek medical attention, this condition may be underdiagnosed. Most researchers agree that von Willebrand disease is the most common genetic bleeding disorder.

Source: MedlinePlus Genetics

Causes

Autosomal Dominant and Baby

Image by TheVisualMD / Domaina

Autosomal Dominant and Baby

Autosomal dominant : an autosomal dominant pattern.

Image by TheVisualMD / Domaina

What Causes Von Willebrand Disease?

Variants in the VWF gene cause von Willebrand disease. The VWF gene provides instructions for making a blood clotting protein called von Willebrand factor, which is essential for the formation of blood clots.

After an injury, clots protect the body by sealing off damaged blood vessels and preventing further blood loss. Von Willebrand factor acts as a glue that holds blood clots together and prevents the breakdown of other blood clotting proteins. If von Willebrand factor does not function normally or too little of the protein is available, blood clots cannot form properly. Abnormally slow blood clotting causes the prolonged bleeding episodes seen in people with von Willebrand disease.

The three types of von Willebrand disease are classified based on the amount of von Willebrand factor that is produced or its ability to function. Variants in the VWF gene that reduce the amount of von Willebrand factor cause type 1 von Willebrand disease. In type 1C, the amount of von Willebrand factor is low because the protein is removed from the body more quickly than usual. People with type 1 von Willebrand disease have varying amounts of von Willebrand factor in their bloodstream. Some people with a mild case of type 1 never experience a prolonged bleeding episode.

Variants that impair the function of von Willebrand factor cause the four subtypes of type 2 von Willebrand disease. Affected individuals produce a normal amount of von Willebrand factor, but the protein cannot function properly.

In type 2A, von Willebrand factor is not the right size and cannot help form clots.

In type 2B, von Willebrand factor forms clots too easily. The clots are removed from the body, so there is not enough von Willebrand factor available when it is needed for clotting.

In types 2M and 2N, von Willebrand factor is unable to interact with other structures or proteins needed to form blood clots.

People with type 2 von Willebrand disease can have bleeding episodes of varying severity depending on the extent of the von Willebrand factor abnormalities, but the bleeding episodes are typically similar to those seen in type 1.

Variants that severely reduce or eliminate von Willebrand factor cause type 3 von Willebrand disease. People with type 3 von Willebrand disease usually have severe bleeding episodes.

Source: MedlinePlus Genetics

Additional Materials (4)

How the body utilizes von Willebrand factor to form a clot

Video by Bleeding Disorders Community/YouTube

von Willebrand disease - Platelet adhesion and aggregation - MADE EASY

Video by Daily Med Ed/YouTube

Von Willebrand Factor (vWF)

Video by Medicosis Perfectionalis/YouTube

Von Willebrand Disease | Pathophysiology, Types, Symptoms and Treatment

Video by JJ Medicine/YouTube

1:37

How the body utilizes von Willebrand factor to form a clot

Bleeding Disorders Community/YouTube

5:11

von Willebrand disease - Platelet adhesion and aggregation - MADE EASY

Daily Med Ed/YouTube

14:08

Von Willebrand Factor (vWF)

Medicosis Perfectionalis/YouTube

14:06

Von Willebrand Disease | Pathophysiology, Types, Symptoms and Treatment

JJ Medicine/YouTube

VWF Gene

Ideogram of human chromosome 12

Image by Office of Biological and Environmental Research of the U.S. Department of Energy Office of Science, the Biological and Environmental Research Information System, Oak Ridge National Laboratory.

Ideogram of human chromosome 12

Selected genes, traits, and disorders associated with the chromosome listed; (blue and violet) regions reflecting the unique patterns of light and dark bands seen on human chromosomes stained to allow viewing through a light microscope; (red) the centromere, or constricted portion, of each chromosome; (yellow) chromosomal regions that vary in staining intensity and sometimes are called hererochromatin (meaning “different color”); (lines between yellow) variable regions, called stalks, that connect a very small chromosome arm (a “satellite”) to the chromosome.

Image by Office of Biological and Environmental Research of the U.S. Department of Energy Office of Science, the Biological and Environmental Research Information System, Oak Ridge National Laboratory.

VWF Gene: Von Willebrand Factor

Normal Function

The VWF gene provides instructions for making a blood clotting protein called von Willebrand factor. This protein contains regions that attach (bind) to specific cells and proteins during the formation of a blood clot. After an injury, clots protect the body by sealing off damaged blood vessels and preventing further blood loss.

Von Willebrand factor is made within endothelial cells, which line the inside surface of blood vessels, and bone marrow cells. The factor is made of several identical subunits. To facilitate binding to various cells and proteins, these subunits are cut into smaller pieces by an enzyme called ADAMTS13. Von Willebrand factor helps platelets stick together and adhere to the walls of blood vessels at the site of a wound. These groups of platelets form temporary clots, plugging holes in blood vessel walls to help stop bleeding. Von Willebrand factor also carries another blood clotting protein, coagulation factor VIII, to the area of clot formation.

Health Conditions Related to Genetic Changes

Von Willebrand disease

More than 300 mutations in the VWF gene have been found to cause von Willebrand disease. Mutations in the VWF gene that reduce the amount of von Willebrand factor cause type 1 von Willebrand disease. People with type 1 von Willebrand disease have von Willebrand factor in their bloodstream, but at reduced amounts. Mutations that disrupt the function of the von Willebrand factor cause the four subtypes of type 2 von Willebrand disease. These mutations usually change one of the protein building blocks (amino acids) used to make von Willebrand factor, which can disrupt the factor's ability to bind to various cells and proteins needed to form a blood clot. Mutations that result in an abnormally short, nonfunctional von Willebrand factor generally cause the more severe type 3 von Willebrand disease. A reduction in the amount of von Willebrand factor or problems with its function slows the formation of blood clots, which causes the prolonged bleeding episodes seen in von Willebrand disease.

Other Names for This Gene

coagulation factor VIII VWF
F8VWF
VWD

Genomic Location

The VWF gene is found on chromosome 12.

Source: MedlinePlus Genetics

Additional Materials (1)

How von Willebrand Factor and ADAMTS13 Regulate Clotting

Video by American Society of Hematology/YouTube

0:37

How von Willebrand Factor and ADAMTS13 Regulate Clotting

American Society of Hematology/YouTube

Inheritance

Inheritance

Image by TheVisualMD

Inheritance

Infant and his chromosomes

Image by TheVisualMD

How Is Von Willebrand Disease Inherited?

Most people who have von Willebrand disease (VWD) are born with it. VWD is caused by genetic changes that are almost always inherited (passed down) from a parent to a child. A person’s genes provide instructions on how to make proteins, such as the von Willebrand factor (VWF) protein. Each person has two copies of most genes, one from his or her mother and one from his or her father. Each copy is called an allele. In people who have VWD, there is a change in the gene for making the VWF protein, called a VWD allele. VWD can be passed down from either the mother or the father or both parents to the child. There are two different ways that VWD can be inherited, autosomal dominant or autosomal recessive, depending on the type of VWD present.

Type 1 and Most Type 2 VWD

Autosomal dominant VWD is caused by changes in only one copy of the gene related to the disorder. In autosomal dominant inheritance, a child will inherit the bleeding disorder if he or she gets a VWD allele (the form of the gene that has a genetic change causing VWD) from one parent who has the disorder. The child of a mother or a father who has one of these types of VWD has a 1 in 2 (50%) chance of getting a VWD allele and having VWD. The symptoms may be worse than the parent’s or not as bad. There is also a 1 in 2 (50%) chance that the child will not get the VWD allele; in this case, the child will not have VWD and can’t pass it down to his or her children.

Rarely, both parents may have VWD. When this happens, the child could get either one VWD allele and one normal allele and have VWD like the parents (1 in 2 chance, or 50%) or get two VWD alleles and have a more severe form of the disease than the parents (1 in 4 chance, or 25%). There is a 1 in 4 (25%) chance that the child will not get a VWD allele from either parent; in this case, the child will not have VWD and can’t pass it down to his or her children.

If one parent has severe type 1 VWD that was inherited from both of his or her parents, meaning that he or she has 2 VWD alleles, and the other parent does not have an allele that can cause VWD, all children will get only one VWD allele and have type 1 VWD that is less severe than the parent who has 2 VWD alleles.

Type 3 VWD and Type 2N VWD

Autosomal recessive VWD is caused by changes in both copies of the gene related to the disorder, so that neither copy works correctly. In autosomal recessive inheritance, both parents have one VWD allele and one normal allele, but they don’t have the disorder; only a person with two VWD alleles will have the disorder. To have VWD, the child must get the VWD allele from both parents (1 in 4 chance, or 25%). A child may also get the VWD allele from one parent (1 in 2 chance, or 50%). If this happens, the child will not have VWD but can pass the VWD allele to his or her children. There is also a 1 in 4 (25%) chance that the child will not get a VWD allele; in this case, the child will not have VWD and can’t pass it down to his or her children.

The child of a parent with type 3 or type 2N VWD will receive a VWD allele from the parent who has VWD but will not have VWD if the other parent does not have a VWD allele. However, all of the children can pass the VWD allele down to their children.

Source: Centers for Disease Control and Prevention (CDC)

Additional Materials (6)

Understanding Autosomal Dominant and Autosomal Recessive Inheritance

Video by Zero To Finals/YouTube

Autosomal Dominant

Video by Children's National Hospital/YouTube

Understanding Autosomal Dominant Conditions

Video by UCD Medicine/YouTube

Autosomal Recessive vs. Autosomal Dominance

Video by Beverly Biology/YouTube

Jordan - Living with von Willebrand Disease (VWD)

Video by CSL Behring/YouTube

5 facts about von Willebrand Disease (vWD)

Video by Comprehensive Bleeding Disorders Center/YouTube

7:06

Understanding Autosomal Dominant and Autosomal Recessive Inheritance

Zero To Finals/YouTube

1:13

Autosomal Dominant

Children's National Hospital/YouTube

3:32

Understanding Autosomal Dominant Conditions

UCD Medicine/YouTube

13:08

Autosomal Recessive vs. Autosomal Dominance

Beverly Biology/YouTube

1:58

Jordan - Living with von Willebrand Disease (VWD)

CSL Behring/YouTube

1:50

5 facts about von Willebrand Disease (vWD)

Comprehensive Bleeding Disorders Center/YouTube

Symptoms

Upper Arm Bruise

Image by Whoisjohngalt

Upper Arm Bruise

A hemotoma of the upper arm of an adult male caused by a punch.

Image by Whoisjohngalt

What Are the Signs and Symptoms of Von Willebrand Disease?

The major signs of VWD are:

Frequent or Hard-to-Stop Nosebleeds

People with VWD might have nosebleeds that

Start without injury (spontaneous)
Occur often, usually five times or more in a year
Last more than 10 minutes
Need packing (gauze placed in the nose) or cautery (a procedure to burn and seal blood vessels) to stop the bleeding

Easy Bruising

People with VWD might experience easy bruising that

Occurs with very little or no trauma or injury
Occurs often (one to four times per month)
Is larger than the size of a quarter
Is not flat and has a raised lump

Heavy Menstrual Bleeding

Women with VWD might have heavy menstrual periods during which they experience

Soaking through a pad or tampon every 1-2 hours (or more often) on the heaviest day(s)
Menstrual bleeding that lasts longer than 7 days from the time bleeding starts until the time it ends
Flooding or gushing of blood
Passing blood clots (tissue) larger than the size of grapes or strawberries
A diagnosis of anemia (not having enough red blood cells) is made as a result of bleeding from heavy periods

Longer than Normal Bleeding After Injury, Surgery, Childbirth, or Dental Work

People with VWD might have longer than normal bleeding after injury, surgery, or childbirth. This bleeding may be characterized in the following ways:

After a cut to the skin, the bleeding lasts more than 5 minutes
Heavy or longer bleeding occurs after surgery. Bleeding sometimes stops but starts up again hours or days later.
Heavy bleeding occurs during or after childbirth

People with VWD might have longer-than-normal bleeding during or after dental work, for example:

Heavy bleeding occurs during or after dental surgery
The surgery site oozes blood longer than 3 hours after the surgery
The surgery site needs packing or cautery to stop the bleeding

The amount of bleeding depends on the type and severity of VWD. Other common bleeding events include:

Blood in the stool (feces) from bleeding into the stomach or intestines
Blood in the urine from bleeding into the kidneys or bladder
Bleeding into joints or internal organs in severe cases (Type 3 VWD)

Source: Centers for Disease Control and Prevention (CDC)

Additional Materials (4)

Let's Talk Symptoms - My Bleeding Disorder

Video by National Hemophilia Foundation/YouTube

Surviving the unknown - von Willebrand disease (VWD)

Video by Octapharma AG, official company YouTube channel/YouTube

What is von Willebrand Disease?

Video by National Hemophilia Foundation/YouTube

Jordan - Living with von Willebrand Disease (VWD)

Video by CSL Behring/YouTube

1:54

Let's Talk Symptoms - My Bleeding Disorder

National Hemophilia Foundation/YouTube

2:28

Surviving the unknown - von Willebrand disease (VWD)

Octapharma AG, official company YouTube channel/YouTube

3:16

What is von Willebrand Disease?

National Hemophilia Foundation/YouTube

1:58

Jordan - Living with von Willebrand Disease (VWD)

CSL Behring/YouTube

Diagnosis

Blood Smear Showing Normal Red Blood Cell Count

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

How Is Von Willebrand Disease Diagnosed?

To find out if a person has von Willebrand disease (VWD), the doctor will ask questions about personal and family histories of bleeding. The doctor also will check for unusual bruising or other signs of recent bleeding and order some blood tests that will measure how the blood clots. The tests will provide information about the amount of clotting proteins present in the blood and if the clotting proteins are working properly. Because certain medications can cause bleeding, even among people without a bleeding disorder, the doctor will ask about recent or routine medications taken that could cause bleeding or make bleeding symptoms worse.

Screening Tests

A combination of blood tests is needed to diagnose the disease. The following screening tests are done first to show if the blood is clotting properly. These tests may show if there is a bleeding disorder, but more tests are needed to tell the type of bleeding disorder present. Screening tests are often normal in VWD, and more specific tests are required.

Complete Blood Count (CBC)

This common test measures the amount of hemoglobin (the red pigment inside red blood cells that carries oxygen), the size and number of red blood cells, and the numbers of different types of white blood cells and platelets found in blood. The CBC is normal among people with VWD. However, if a person with VWD has unusually heavy bleeding or bleeds for a long time, the hemoglobin and the red blood cell count can be low.

Activated Partial Thromboplastin Time (APTT) Test

This test measures how long it takes for blood to clot. It measures the clotting ability of factors VIII (8), IX (9), XI (11), and XII (12). If any of these clotting factors is too low, it will take longer than normal for the blood to clot. The results of this test will show a longer clotting time among some people with VWD. However, the results of this test will be normal among people with mild VWD.

Prothrombin Time (PT) Test

This test also measures the time it takes for blood to clot. It measures primarily the clotting ability of factors I (1), II (2), V (5), VII (7), and X (10). If the level of any one of these factors is too low, it will take longer than normal for the blood to clot. The results of this test will be normal among most people with VWD.

Fibrinogen Test

This test also helps doctors assess a patient’s ability to form a blood clot. This test is ordered either along with other blood clotting tests or when a patient has an abnormal PT or APTT test result, or both. The results of this test will be normal among people with VWD. Fibrinogen is another name for clotting factor I (1).

Diagnostic Tests

Specific tests are required to diagnose which bleeding disorder is there. Often these tests need to be repeated several times before an accurate diagnosis can be made. This is because the levels of clotting factors in the blood vary over time as a result of changes the body might be reacting to―such as stress, pregnancy, and infections―that can affect the test results.

The blood tests that a doctor can order to diagnose VWD (or another platelet disorder) include:

Factor VIII clotting activity―To measure the amount of factor VIII in the blood
Von Willebrand factor antigen―To measure the amount of VWF in the blood
Ristocetin cofactor or other VWF activity―To measure how well the VWF works
Von Willebrand factor multimers―To measure the makeup or structure of the VWF
Platelet aggregation tests―To measure how well the platelets are working

Source: Centers for Disease Control and Prevention (CDC)

Additional Materials (5)

Interpreting tests for von Willebrand disease (VWD)

Video by Medmastery/YouTube

Diagnosing von Willebrand Disease - The Balancing Act

Video by The Balancing Act/YouTube

Diagnosis | ASH Clinical Practice Guidelines on Von Willebrand Disease (VWD)

Video by American Society of Hematology/YouTube

Prothrombin Time and Activated Prothrombin Time

Video by LabsforLifeProject/YouTube

Coagulation Tests (PT, aPTT, TT, Fibrinogen, Mixing Studies,..etc)

Video by Medicosis Perfectionalis/YouTube

5:54

Interpreting tests for von Willebrand disease (VWD)

Medmastery/YouTube

8:07

Diagnosing von Willebrand Disease - The Balancing Act

The Balancing Act/YouTube

4:00

Diagnosis | ASH Clinical Practice Guidelines on Von Willebrand Disease (VWD)

American Society of Hematology/YouTube

30:28

Prothrombin Time and Activated Prothrombin Time

LabsforLifeProject/YouTube

19:22

Coagulation Tests (PT, aPTT, TT, Fibrinogen, Mixing Studies,..etc)

Medicosis Perfectionalis/YouTube

Complete Blood Count

Complete Blood Count

Also called: CBC, Full Blood Count, Blood Cell Count, Hemotology Panel

A complete blood count (CBC) is often part of a routine exam. It is used to measure different parts and features of your blood. A CBC can help detect a variety of disorders including infections, anemia, diseases of the immune system, and blood cancers.

Complete Blood Count

Also called: CBC, Full Blood Count, Blood Cell Count, Hemotology Panel

A complete blood count (CBC) is often part of a routine exam. It is used to measure different parts and features of your blood. A CBC can help detect a variety of disorders including infections, anemia, diseases of the immune system, and blood cancers.

A complete blood count, or CBC, is a blood test that measures many different parts and features of your blood, including:
- Red blood cells, which carry oxygen from your lungs to the rest of your body.
- White blood cells, which fight infections and other diseases. There are five major types of white blood cells. A CBC test measures the total number of white cells in your blood. A different test called a CBC with differential measures the number of each type of these white blood cells.
- Platelets, which stop bleeding by helping your blood to clot.
- Hemoglobin, a protein in red blood cells that carries oxygen from your lungs to the rest of your body.
- Hematocrit, a measurement of how much of your blood is made up of red blood cells.
- Mean corpuscular volume (MCV), a measure of the average size of your red blood cells.
Other names for a complete blood count: CBC, full blood count, blood cell count
Your health care provider may have ordered a complete blood count as part of your checkup or to monitor your overall health. The test may also be used to:
- Help diagnose blood diseases, infection, immune system disorders, or other medical conditions
- Check for changes in an existing blood disorder
A CBC counts the cells in your blood. There are many reasons your levels may not be in the normal range. For example:
- Abnormal levels of red blood cells, hemoglobin, or hematocrit may be a sign of anemia, heart disease, or too little iron in your body.
- Low white cell count may be a sign of an autoimmune disorder, bone marrow disorder, or cancer.
- High white cell count may be a sign of an infection or a reaction to medicine.
If any of your levels are abnormal, it doesn't always mean you have a medical condition that needs treatment. Diet, activity level, medicines, a menstrual period, not drinking enough water, and other factors can affect the results. Talk with your provider to learn what your results mean.
1. Complete Blood Count (CBC): MedlinePlus Medical Test [accessed on Jan 20, 2024]
2. Blood Tests - Blood Tests | NHLBI, NIH. Mar 24, 2022 [accessed on Jan 20, 2024]

Additional Materials (25)

Reticulocyte Count, Hemorrhage/Chronic Blood Loss

Reticulocytes are immature red blood cells (RBCs) released into the bloodstream from the bone marrow in which they developed. Normally, only a tiny percentage red blood cells circulating in the bloodstream are reticulocytes. The reticulocyte count rises, however, when bone marrow is called upon to produce more RBCs, in conditions such as heavy bleeding or certain types of anemia.

Image by TheVisualMD

Blood sample

During the blood collection process, medical personnel gather additional blood samples to test for an array of blood disorders and communicable diseases. Every unit of blood is rigorously tested before approved for transfusion into a patient.

Image by United States Marine Corps

Phlebotomy

Venipuncture (blood draw / collection) in the left arm of a male.

Image by MatthewLammers

Blood and Related Conditions

Blood and Related Conditions : Anemia results when there are too few red blood cells circulating in the bloodstream to deliver adequate oxygen to body tissues. There are different types and causes of anemia, including malnutrition, chronic bleeding, and diseases that result in red blood cells either being destroyed too quickly or produced too slowly.

Image by TheVisualMD

Components of Blood

Components of Blood : Our blood is composed of many different components, the largest categories being red and white blood cells (blood-clotting platelets are another key component) and the liquid portion known as blood plasma. A Complete Blood Count (CBC) includes several of the most basic, yet important, measurements of these components.

Image by TheVisualMD

Blood fractionation

Vial of separated blood. The middle layer is a type of sterile goo which separates the blood from the rest of what's drawn.

Image by Wheeler Cowperthwaite from Reno, USA

Whole Blood

A Red Cross whole blood donation before any separation

Image by Whoisjohngalt

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

Medical Checkups

Image by TheVisualMD

Medical Checkups

Most doctors believe that people should have regular checkups as a part of preventive treatment. Regular health exams can help find problems before they begin, or in their early stages, when the chances of successful treatment are best. Blood Pressure Reading: Photo Copyright 2005, James Gathany

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

Full Blood Count – what it tells your doctor about your health

Video by Pathology Tests Explained/YouTube

Complete Blood Count (CBC)

Video by Medicosis Perfectionalis/YouTube

Complete Blood Count

Video by Tom Wade MD/YouTube

high white blood cell count Video

Video by itbestshop/YouTube

Complete Blood Count pt1

Video by Med Immersion/YouTube

Complete Blood Count pt2

Video by Med Immersion/YouTube

This browser does not support the video element.

Normal Red Blood Cell (RBC) Count

An animation simulating a view of a healthy count of red blood cells as viewed in a slide projector or under a microscope. Initially, the screen in white with a circular black vignette along its borders. Then a still showing red blood cells slides up from the bottom left filling the screen and then comes into focus. The red blood cells resemble those taken from an scanning electron micrograph (SEM) and fill up the given space on the screen.

Video by TheVisualMD

This browser does not support the video element.

Anemic Blood Flow

Camera is stationary as it focuses on a capillary in a cell bed demonstrating anemic blood flow and it's lower red blood cell count.

Video by TheVisualMD

This browser does not support the video element.

Anemic Red Blood Cell (RBC) Count

An animation simulating a view of an unhealthy count of red blood cells as viewed in a slide projector or under a microscope. Initially, the screen in white with a circular black vignette along its borders. Then a still showing red blood cells on a light red background slides up from the bottom left filling the screen and then comes into focus. The red blood cells resemble those taken from an scanning electron micrograph (SEM). There are only a few red blood cells in this slide indicative of the low amount typical of some one who is anemic.

Video by TheVisualMD

This browser does not support the video element.

Anemic Red Blood Cell (RBC) Count

An animation simulating a close-up of an unhealthy count of red blood cells as viewed in a slide projector or under a microscope. Initially, the screen in white with a circular black vignette along its borders. Then a still showing red blood cells on a light red background slides up from the bottom left filling the screen and then comes into focus. Throughout the animation, the slide jitters a little. The red blood cells resemble those taken from an scanning electron micrograph (SEM). In this close up there are a few red blood cells along with a few white blood cells.

Video by TheVisualMD

Why Blood Tests Can Save Your Life

Video by Seeker+/YouTube

Introduction to lab values and normal ranges | Health & Medicine | Khan Academy

Video by khanacademymedicine/YouTube

Low blood counts and the risk of infection in cancer patients | Norton Cancer Institute

Video by Norton Healthcare/YouTube

Dr. Erba Describes Proper Diagnostic Testing of CML

Video by OncLiveTV/YouTube

Reticulocyte Count, Hemorrhage/Chronic Blood Loss

TheVisualMD

Blood sample

United States Marine Corps

Phlebotomy

MatthewLammers

Blood and Related Conditions

TheVisualMD

Components of Blood

TheVisualMD

Blood fractionation

Wheeler Cowperthwaite from Reno, USA

Whole Blood

Whoisjohngalt

White Blood Cells Rotation

TheVisualMD

Medical Checkups

TheVisualMD

Medical Checkups

TheVisualMD

2:12

Complete Blood Count, and Baselining Your Health

TheVisualMD

4:18

Full Blood Count – what it tells your doctor about your health

Pathology Tests Explained/YouTube

7:04

Complete Blood Count (CBC)

Medicosis Perfectionalis/YouTube

4:11

Complete Blood Count

Tom Wade MD/YouTube

8:22

high white blood cell count Video

itbestshop/YouTube

16:12

Complete Blood Count pt1

Med Immersion/YouTube

22:14

Complete Blood Count pt2

Med Immersion/YouTube

0:06

Normal Red Blood Cell (RBC) Count

TheVisualMD

0:07

Anemic Blood Flow

TheVisualMD

0:14

Anemic Red Blood Cell (RBC) Count

TheVisualMD

0:14

Anemic Red Blood Cell (RBC) Count

TheVisualMD

8:29

Why Blood Tests Can Save Your Life

Seeker+/YouTube

10:42

Introduction to lab values and normal ranges | Health & Medicine | Khan Academy

khanacademymedicine/YouTube

1:32

Low blood counts and the risk of infection in cancer patients | Norton Cancer Institute

Norton Healthcare/YouTube

2:39

Dr. Erba Describes Proper Diagnostic Testing of CML

OncLiveTV/YouTube

Red Blood Cells

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
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
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.
1. Red Blood Cell (RBC) Count: MedlinePlus Medical Test [accessed on Jan 20, 2024]
2. RBC count: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
3. 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

White Blood Cells

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.
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 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.
1. White Blood Count (WBC): MedlinePlus Medical Test [accessed on Jan 20, 2024]
2. WBC count: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
3. 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

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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

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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

Platelets

Platelet Count

Also called: Platelets, PLT Count, Platelet Adequacy, Thrombocyte Count, Thrombocytopenia Test, Thrombocytosis Test, Platelet count

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.

Platelet Count

Also called: Platelets, PLT Count, Platelet Adequacy, Thrombocyte Count, Thrombocytopenia Test, Thrombocytosis Test, Platelet count

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 health.
(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
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
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
1. Platelet Tests: MedlinePlus Medical Test [accessed on Jan 20, 2024]
2. Platelet Count (PLT) Blood Test - Testing.com. Dec 19, 2023 [accessed on Jan 20, 2024]
3. 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

Video by Merck Manuals/YouTube

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

Platelets Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing

Video by NURSINGcom/YouTube

Platelets Explained in Two Minutes

Video by American Red Cross/YouTube

The life and times of RBCs and platelets

Video by khanacademymedicine/YouTube

Platelet Development

OpenStax College

Sensitive content

This media may include sensitive content

Platelet Disorders

Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)

Scheme of a blood sample after centrifugation

KnuteKnudsen (talk)

0:48

Decode Your Blood Test: Platelets 💉 | Merck Manual Consumer Version

Merck Manuals/YouTube

2:12

Complete Blood Count, and Baselining Your Health

TheVisualMD

3:54

Platelets Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing

NURSINGcom/YouTube

1:47

Platelets Explained in Two Minutes

American Red Cross/YouTube

10:35

The life and times of RBCs and platelets

khanacademymedicine/YouTube

Hemoglobin

Hemoglobin Blood Test

Also called: Hemoglobin, Hgb

A hemoglobin test measures the levels of hemoglobin in your blood. Hemoglobin is an iron-rich protein in red blood cells that carries oxygen. Abnormal levels may mean you have anemia or another blood disorder.

Hemoglobin Blood Test

Also called: Hemoglobin, Hgb

A hemoglobin test measures the levels of hemoglobin in your blood. Hemoglobin is an iron-rich protein in red blood cells that carries oxygen. Abnormal levels may mean you have anemia or another blood disorder.

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Use the slider below to see how your results affect your health.
g/dL
13.8
17.2
Your result is Normal.
Heme, an iron-containing molecule, combines with globin proteins to form hemoglobin, which carries oxygen in red blood cells from the lungs to the rest of the body.
Related conditions
Your health care provider may order the test as part of a routine exam, or if you have:
- Symptoms of anemia, which include weakness, dizziness, and cold hands and feet
- A family history of thalassemia, sickle cell anemia, or other inherited blood disorder
- A diet low in iron and other minerals
- A long-term infection
- Excessive blood loss from an injury or surgical procedure
There are many reasons your hemoglobin levels may not be in the normal range.
Low hemoglobin levels may be a sign of:
- Different types of anemia
- Thalassemia
- Iron deficiency
- Liver disease
- Cancer and other diseases
High hemoglobin levels may be a sign of:
- Lung disease
- Heart disease
- Polycythemia vera, a disorder in which your body makes too many red blood cells. It can cause headaches, fatigue, and shortness of breath.
If any of your levels are abnormal, it doesn't always mean you have a medical condition that needs treatment. Diet, activity level, medicines, a menstrual period, and other factors can affect the results. You may also have higher than normal hemoglobin levels if you live in a high altitude area. Talk with your provider to learn what your results mean.
1. Hemoglobin Test: MedlinePlus Medical Test [accessed on Jan 20, 2024]
2. Hemoglobin: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
3. Hemoglobin - Health Encyclopedia - University of Rochester Medical Center [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 (16)

Hemoglobin | Human anatomy and physiology | Health & Medicine | Khan Academy

Video by Khan Academy/YouTube

Blood, Part 2 - There Will Be Blood: Crash Course A&P #30

Video by CrashCourse/YouTube

Haemoglobin

Video by Wellcome Trust/YouTube

Hemoglobin A1c & Diabetes

Video by DiabeTV/YouTube

Hemoglobin Molecule

Molecule of hemoglobin.

Image by TheVisualMD

Hemoglobin A1C Molecule

Hemoglobin is a protein found inside red blood cells that carries oxygen from the lungs to cells throughout the body. Hemoglobin also binds with glucose. Diabetics have too much glucose in the bloodstream and this extra glucose binds (or glycates) with hemoglobin. Glycated hemoglobin usually stays glycated for the life of the red blood cell (about 3 months). Therefore, the percentage of hemoglobin that is glycated (measured as A1C) reflects glucose levels that have affected red blood cells up to 3 months in the past. The hemoglobin A1C test measures the percentage of hemoglobin bound to blood sugar (glucose); the test is used to diagnose type 1 and type 2 diabetes. Because the test results reflect average blood sugar levels over a period of 2-3 months (rather than daily fluctuations), the hemoglobin A1C test is also used to gauge how well patients are managing their diabetes over time.

Image by TheVisualMD

Hemoglobin A1C: Red Blood Cells

Red blood cells use the iron-rich protein hemoglobin to carry oxygen from the lungs to cells throughout the body and return carbon dioxide to the lungs. The percentage of hemoglobin bound to blood glucose (hemoglobin A1C) is used to diagnose diabetes.

Image by TheVisualMD

Hemoglobin of Red Blood Cell

Hemoglobin is an iron-containing protein found in red blood cells that binds oxygen and carbon dioxide for transport and delivery to different parts of the body.

Image by TheVisualMD

Hemoglobin Molecule

Hemoglobin is an iron-rich protein that is packed inside RBCs. It is a structurally complex molecule that can change shape to either hold or release oxygen, depending on the body's need. There are close to 300 million hemoglobin molecules within each RBC.

Image by TheVisualMD

Hemoglobin Molecule Heme Group

A heme group in a hemoglobin molecule consists of an iron atom bound equally to four nitrogen atoms, all lying in one plane. The iron atom is the site of oxygen binding.

Image by TheVisualMD

This browser does not support the video element.

Hemoglobin Within Red Blood Cell (RBC)

A red blood cell rushes toward the camera, the camera enters the cell to focus on all of the hemoglobin molecules within

Video by TheVisualMD

Hemoglobin, Carbon Monoxide

Hemoglobin is an iron-containing protein that enables red blood cells to deliver oxygen from the lungs to cells throughout the body. But the same binding site on the hemoglobin molecule has an even stronger affinity for carbon monoxide, which is why we are so susceptible to poisoning by this deadly gas; carbon monoxide grabs all the binding sites and starves the body's tissues of oxygen

Image by TheVisualMD

This browser does not support the video element.

Hemoglobin A1c

The hemoglobin A1c test measures the percentage of hemoglobin bound to blood sugar (glucose); the test is used to diagnose type 1 and type 2 diabetes. Because the test results reflect average blood sugar levels over a period of 2-3 months (rather than daily fluctuations), the hemoglobin A1C test is also used to gauge how well patients are managing their diabetes over time.

Video by TheVisualMD

Hemoglobin A1c

The hemoglobin A1c test measures the percentage of hemoglobin bound to blood sugar (glucose); the test is used to diagnose type 1 and type 2 diabetes. Because the test results reflect average blood sugar levels over a period of 2-3 months (rather than daily fluctuations), the hemoglobin A1C test is also used to gauge how well patients are managing their diabetes over time.

Image by TheVisualMD

Hemoglobin: O2 Binding Hemoglobin

Hemoglobin normally binds to life-sustaining oxygen. But the same binding site on the hemoglobin molecule has an even stronger affinity for carbon monoxide, which is why we are so susceptible to poisoning by this deadly gas.

Image by TheVisualMD

HemoglobinA1C

Hemoglobin Test for O2 Binding Hemoglobin : A hemoglobin test is a measurement of your blood's oxygen-carrying capacity. High levels of hemoglobin can be the result of dehydration, lung disease and other conditions. Low levels of hemoglobin indicate that there is a shortage of red blood cells; this can be the result of RBCs being lost or destroyed too quickly or produced too slowly. Hemoglobin is an iron-containing protein that enables red blood cells to deliver oxygen from the lungs to cells throughout the body. But the same binding site on the hemoglobin molecule has an even stronger affinity for carbon monoxide, which is why we are so susceptible to poisoning by this deadly gas; carbon monoxide grabs all the binding sites and starves the body's tissues of oxygen.

Image by TheVisualMD

14:34

Hemoglobin | Human anatomy and physiology | Health & Medicine | Khan Academy

Khan Academy/YouTube

10:01

Blood, Part 2 - There Will Be Blood: Crash Course A&P #30

CrashCourse/YouTube

5:31

Haemoglobin

Wellcome Trust/YouTube

1:43

Hemoglobin A1c & Diabetes

DiabeTV/YouTube

Hemoglobin Molecule

TheVisualMD

Hemoglobin A1C Molecule

TheVisualMD

Hemoglobin A1C: Red Blood Cells

TheVisualMD

Hemoglobin of Red Blood Cell

TheVisualMD

Hemoglobin Molecule

TheVisualMD

Hemoglobin Molecule Heme Group

TheVisualMD

0:27

Hemoglobin Within Red Blood Cell (RBC)

TheVisualMD

Hemoglobin, Carbon Monoxide

TheVisualMD

0:27

Hemoglobin A1c

TheVisualMD

Hemoglobin A1c

TheVisualMD

Hemoglobin: O2 Binding Hemoglobin

TheVisualMD

HemoglobinA1C

TheVisualMD

Hematocrit

Hematocrit Blood Test

Also called: Hematrocit, HCT, Crit, Packed Cell Volume, PCV

Hematocrit is a blood test that measures how much of a person's blood is made up of red blood cells. Hematocrit levels that are too high or too low can be a sign of a blood disorder, dehydration, or other medical conditions that affect your blood.

Hematocrit Blood Test

Also called: Hematrocit, HCT, Crit, Packed Cell Volume, PCV

Hematocrit is a blood test that measures how much of a person's blood is made up of red blood cells. Hematocrit levels that are too high or too low can be a sign of a blood disorder, dehydration, or other medical conditions that affect your blood.

{"label":"Hematocrit reference range","scale":"lin","step":0.1,"hideunits":false,"items":[{"flag":"abnormal","label":{"short":"Low","long":"Low","orientation":"horizontal"},"values":{"min":0,"max":40.7},"text":"A hematocrit level below the normal range, meaning the person has too few red blood cells, is called anemia.","conditions":["Anemia","Bleeding","Bone marrow cancers and disorders","Chronic illness","Chronic kidney disease","Destruction of red blood cells (hemolysis)","Leukemia","Malnutrition","Too little iron, folate, vitamin B12, and vitamin B6 in the diet","Too much water in the body"]},{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":40.7,"max":50.3},"text":"Normal hematocrit levels vary based on age and race. In adults, normal levels for men range from 41%-50%. For women, the normal range is slightly lower: 36%-44%.","conditions":[]},{"flag":"abnormal","label":{"short":"High","long":"High","orientation":"horizontal"},"values":{"min":50.3,"max":100},"text":"A hematocrit level above the normal range, meaning too many red blood cells, may indicate polycythemia or erythrocytosis. High hematocrits can be seen in people living at high altitudes and in chronic smokers.","conditions":["Polycythemia vera","Congenital heart disease","Exposure to high altitude","Failure of the right side of the heart","Low levels of oxygen in the blood","Scarring or thickening of the lungs","Too little water in the body (dehydration)"]}],"units":[{"printSymbol":"%","code":"%","name":"percent"}],"value":45.5}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
%
40.7
50.3
Your result is Normal.
Normal hematocrit levels vary based on age and race. In adults, normal levels for men range from 41%-50%. For women, the normal range is slightly lower: 36%-44%.
Related conditions
Your health care provider may order a hematocrit test as part of your regular checkup or to monitor your health if you are being treated for cancer or have an ongoing health condition. Your provider may also order this test if you have symptoms of a red blood cell disorder, such as anemia or polycythemia:
Symptoms of anemia (too few red blood cells) may include:
- Shortness of breath
- Weakness or fatigue
- Headache
- Dizziness
- Arrhythmia (a problem with the rate or rhythm of your heartbeat)
Symptoms of polycythemia (too many red blood cells) may include:
- Headache
- Feeling light-headed or dizzy
- Shortness of breath
- Weakness or fatigue
- Skin symptoms such as itching after a shower or bath, burning, or a red face
- Heavy sweating, especially during sleep
- Blurred or double vision and blind spots
- Bleeding gums and heavy bleeding from small cuts
Your hematocrit test results are reported as a number. That number is the percentage of your blood that's made of red blood cells. For example, if your hematocrit test result is 42, it means that 42% of your blood is red blood cells and the rest is white blood cells, platelets, and blood plasma.
A hematocrit level that's lower than normal may be a sign that:
- Your body doesn't have enough red blood cells (anemia). There are many types of anemia that can be caused by different medical conditions.
- Your body is making too many white blood cells, which may be caused by:
  Bone marrow disease
  Certain cancers, including leukemia, lymphoma, multiple myeloma, or cancers that spread to the bone marrow from other parts of the body
A hematocrit level that's higher than normal may be a sign that:
- Your body is making too many red blood cells, which may be caused by:
  Lung disease
  Congenital heart disease
  Heart failure
  Polycythemia
- Your blood plasma level is too low, which may be caused by:
  Dehydration, the most common cause of a high hematocrit
  Shock
If your results are not in the normal range, it doesn't always mean that you have a medical condition that needs treatment. Living at high altitudes where there's less oxygen in the air may cause a high hematocrit. That's because your body responds to low oxygen levels by making more red blood cells so that you get the oxygen you need.
Pregnancy can cause a low hematocrit. That's because the body has more fluid than normal during pregnancy, which decreases the percentage that's made of red blood cells.
To learn what your test results mean, talk with your provider.
1. Hematocrit Test: MedlinePlus Medical Test [accessed on Jan 20, 2024]
2. Hematocrit: MedlinePlus Medical Encyclopedia [accessed on Jan 20, 2024]
3. Hematrocit Blood Test - Testing.com. Sep 13, 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 (30)

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

Vial of Centrifuged Blood

Blood is made up of red and white blood cell (as well as platelets), suspended in a liquid known as blood plasma. Plasma, which makes up 55% of our blood's volume, is a clear liquid (mainly water) that transports food molecules, hormones, waste as well as a wide range of dissolved chemicals. Red cells, which normally make up 40-50% of total blood volume, are produced continuously in our bone marrow at the rate of about 2-3 million cells per second. White cells make up a very small part of blood's volume-normally only about 1% in healthy people. This image shows two vials of centrifuged blood. The left vial shows healthy amount of red blood cells in female (36-44%) ; The right vial shows healthy amount of red blood cells in male (41-50%). The hematocrit (along with the hemoglobin test) is the central test to diagnosing anemia in that it indicates the amount of RBCs in the blood.

Image by TheVisualMD

Red Blood Cells, Bone Marrow

A skeleton may have a dry and lifeless Halloween image, but bone is actually dynamic, living tissue. Bone is not uniformly solid; within its interior is a network of cavities that house blood vessels and marrow. Bone marrow, particularly in larger bones, is where stem cells give rise to red blood cells (erythrocytes) as well as white blood cells (leukocytes) and blood clotting agents (platelets). As the source of blood cells, the bone marrow is critical to health. Disease or damage to bone marrow can result in either too many or too few blood cells.

Image by TheVisualMD

Anemia: Basic lab tests - hematocrit, hemoglobin, reticulocyte, MCV, morphology

Video by retic20/YouTube

Hematocrit Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing

Video by NURSINGcom/YouTube

Hematocrit, Dehydration

Blood is composed of cells (primarily red blood cells, but also white blood cells and cell fragments called platelets) along with a liquid portion known as plasma. The ratio of the volume of red blood cells to the volume of plasma is an important health indicator and is known as the hematocrit. The most common cause of a high hematocrit is dehydration, which is usually temporary and easily remedied by increasing fluid intake, thereby restores the balance between RBCs and blood plasma volume.

Image by TheVisualMD

Hematocrit, Anemia

Blood is composed of cells (primarily red blood cells, but also white blood cells and cell fragments called platelets) along with a liquid portion known as plasma. The ratio of the volume of red blood cells to the volume of plasma is an important health indicator and is known as the hematocrit. A low hematocrit usually indicates anemia, which occurs when red blood cells are being either destroyed too quickly or produced too slowly; with fewer red blood cells, less oxygen is delivered to body tissues.

Image by TheVisualMD

Vial of Blood for Hematocrit Test

This image is a vial of blood that has been centrifuged (and thus separated) to determine hematocrit. This vial shows, from top to bottom, 55% plasma, <1% white blood cells, <1% platelets , 45% red blood cells. Hematocrit measures how much of the blood, by volume, is taken up by RBCs. A normal range for hematocrit is 41 to 50 percent in men and 36 to 44 percent in women. In many cases, a reading below the normal range for hematocrit will lead to a diagnosis of CKD-related anemia.This other diagnostic test is the hemoglobin test, which measures the amount of hemoglobin molecules in the blood and is a good indicator of the body's ability to carry oxygen throughout the body.

Image by TheVisualMD

Hematocrit: Bone Marrow

Bone marrow produces about 2 million red blood cells (RBCs) a second to maintain a healthy hematocrit. Many conditions, including kidney disease, chemotherapy, and dietary deficiencies, can reduce RBC production, while others can result in too many RBCs.

Image by TheVisualMD

Hematocrit: Blood Cells

The hematocrit is another way to look at the health of red blood cells (RBCs). Blood is composed of cells (primarily RBCs) and a liquid portion called plasma. The proportions of RBCs and plasma must be kept in balance and this is what the hematocrit measures.

Image by TheVisualMD

Blood

Components of Blood : Blood is mostly made up of plasma and red and white blood cells. But it also contains many other substances as well, like platelets, hormones, nutrients such as glucose, and fats like cholesterol. Blood is the fluid of life, transporting oxygen from the lungs to body tissue and carbon dioxide from body tissue to the lungs.

Image by TheVisualMD

Hematocrit

Hematocrit Blood Vials : If you are at risk for cardiovascular disease, your doctor may order a cholesterol and triglyceride level test as well as a complete blood count (CBC). Abnormal results may be the first clue in determining risk of and in diagnosing cardiovascular disease.

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

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

This browser does not support the video element.

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.

Video by TheVisualMD

Components of Blood

Components of Blood : Our blood is composed of many different components, the largest categories being red and white blood cells (blood-clotting platelets are another key component) and the liquid portion known as blood plasma. A Complete Blood Count (CBC) includes several of the most basic, yet important, measurements of these components.

Image by TheVisualMD

Blood and Related Conditions

Blood and Related Conditions : Anemia results when there are too few red blood cells circulating in the bloodstream to deliver adequate oxygen to body tissues. There are different types and causes of anemia, including malnutrition, chronic bleeding, and diseases that result in red blood cells either being destroyed too quickly or produced too slowly.

Image by TheVisualMD

Pellet of Lymphocyte Cells Created in the Centrifuge

This photograph shows Wendy Watford, Ph.D. holding a test tube containing isolated lymphocyte cells. The cells were spun in a centrifuge to create a pellet at the bottom of the test tube. The cells will be labeled with CFSE dye, which will stain the membranes of the cells. After culturing the cells for three days she will determine the number of cell divisions that have taken place by measuring the dilution of the CFSE dye. The purpose of the work is to measure the proliferation of lymphocytes under various conditions. The principal investigator for this work is John J. O’Shea, M.D., NIAMS Scientific Director.

Image by NIAMS/Photographer: Rhoda Baer

Red Blood Cells

Digital holographic microscopy (DHM) image of red blood cells.

Image by Egelberg (talk)

Test Tube

Between 5,000 and 8,000 blood serum, fecal, urine, viral and respiratory samples arrive six days a week from U.S. Air Force hospitals and clinics worldwide, as well as some other Department of Defense facilities, for analysis at the Epidemiology Laboratory Service, also known as the "Epi Lab" at the 711th Human Performance Wing’s United States Air Force School of Aerospace Medicine and Public Health at Wright Patterson AFB, Ohio.The lab is a Department of Defense reference laboratory offering clinical diagnostic, public health, and force health screening and testing. (U.S. Air Force photo by J.M. Eddins Jr.)

Image by U.S. Air Force photo by J.M. Eddins Jr.

Phlebotomy

This image was uploaded as part of Wiki Loves e-textbooks contest in Poland.

Image by Sean Michael Ragan

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

Composition of Blood

Composition of Blood

Image by OpenStax College

Hematology | Hematocrit

Video by Ninja Nerd/YouTube

Erythrocyte indices (Hemoglobin, Hematocrit, MCV, MCH & MCHC) What Do These Lab Tests Mean?

Video by Medicosis Perfectionalis/YouTube

How to Interpret RBC Indices (e.g. hemoglobin vs. hematocrit, MCV, RDW)

Video by Strong Medicine/YouTube

Haematocrit or PCV

Video by LabsforLifeProject/YouTube

Packed cell volume/ Hematocrit

Video by Pathology Simplified/YouTube

Fetal hemoglobin and hematocrit | Human anatomy and physiology | Health & Medicine | Khan Academy

Video by khanacademymedicine/YouTube

Smoking, Hematocrit, & Fasting Erythropoietin Concentrations

Video by Mayo Proceedings/YouTube

2:12

Complete Blood Count, and Baselining Your Health

TheVisualMD

Vial of Centrifuged Blood

TheVisualMD

Red Blood Cells, Bone Marrow

TheVisualMD

4:32

Anemia: Basic lab tests - hematocrit, hemoglobin, reticulocyte, MCV, morphology

retic20/YouTube

4:40

Hematocrit Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing

NURSINGcom/YouTube

Hematocrit, Dehydration

TheVisualMD

Hematocrit, Anemia

TheVisualMD

Vial of Blood for Hematocrit Test

TheVisualMD

Hematocrit: Bone Marrow

TheVisualMD

Hematocrit: Blood Cells

TheVisualMD

Blood

TheVisualMD

Hematocrit

TheVisualMD

Blood Smear Showing Reduced Red Blood Cell Count

TheVisualMD

Blood Smear Showing Normal Red Blood Cell Count

TheVisualMD

0:53

Red Blood Cells Carry Oxygen

TheVisualMD

Components of Blood

TheVisualMD

Blood and Related Conditions

TheVisualMD

Pellet of Lymphocyte Cells Created in the Centrifuge

NIAMS/Photographer: Rhoda Baer

Red Blood Cells

Egelberg (talk)

Test Tube

U.S. Air Force photo by J.M. Eddins Jr.

Phlebotomy

Sean Michael Ragan

Red Blood Cells Carry Oxygen

TheVisualMD

Composition of Blood

OpenStax College

10:46

Hematology | Hematocrit

Ninja Nerd/YouTube

8:32

Erythrocyte indices (Hemoglobin, Hematocrit, MCV, MCH & MCHC) What Do These Lab Tests Mean?

Medicosis Perfectionalis/YouTube

7:06

How to Interpret RBC Indices (e.g. hemoglobin vs. hematocrit, MCV, RDW)

Strong Medicine/YouTube

6:14

Haematocrit or PCV

LabsforLifeProject/YouTube

9:16

Packed cell volume/ Hematocrit

Pathology Simplified/YouTube

14:32

Fetal hemoglobin and hematocrit | Human anatomy and physiology | Health & Medicine | Khan Academy

khanacademymedicine/YouTube

6:19

Smoking, Hematocrit, & Fasting Erythropoietin Concentrations

Mayo Proceedings/YouTube

MCV

MCV (Mean Corpuscular Volume) Test

Also called: MCV, MCV Blood Test, Mean Corpuscular Volume, Mean RBC Volume

A mean corpuscular volume (MCV) blood test measures the size of your red blood cells. If blood cells are too small or too large, it may indicate a blood disorder.

MCV (Mean Corpuscular Volume) Test

Also called: MCV, MCV Blood Test, Mean Corpuscular Volume, Mean RBC Volume

A mean corpuscular volume (MCV) blood test measures the size of your red blood cells. If blood cells are too small or too large, it may indicate a blood disorder.

{"label":"MCV reference range","scale":"lin","step":0.1,"hideunits":false,"items":[{"flag":"abnormal","label":{"short":"Low","long":"Low","orientation":"horizontal"},"values":{"min":0,"max":76},"text":"A low MCV indicates that the red blood cells are smaller than normal, or microcytic.","conditions":["Microcytic anemia","Iron-deficiency\u00a0anemia\u00a0or other types of anemia","Thalassemia"]},{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":76,"max":96},"text":"A normal MCV indicates that the red blood cells are normal average size, or normocytic. Normal results vary based on the laboratory and the method used.","conditions":[]},{"flag":"abnormal","label":{"short":"High","long":"High","orientation":"horizontal"},"values":{"min":96,"max":200},"text":"A high MCV indicates that the red blood cells are larger than normal, or macrocytic.","conditions":["Macrocytic anemia","Vitamin B12 deficiency","Folic acid deficiency","Liver disease","Hypothyroidism"]}],"units":[{"printSymbol":"fL","code":"fL","name":"femtoliter"}],"value":86}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
fL
76
96
Your result is Normal.
A normal MCV indicates that the red blood cells are normal average size, or normocytic. Normal results vary based on the laboratory and the method used.
Related conditions
Your health care provider may order a complete blood count, which includes an MCV test, as part of your regular checkup. You may also have the test if you have a chronic (long-lasting) condition that could lead to anemia or if you have the symptoms of anemia:
- Shortness of breath
- Weakness or fatigue
- Headache
- Dizziness
- Arrhythmia (a problem with the rate or rhythm of your heartbeat)
An MCV test alone cannot diagnose any disease. Your provider will use the results of your MCV, other test results, and your medical history to make a diagnosis.
If your results show that your red blood cells are smaller than normal, it may be a sign of:
- Certain types of anemia, including iron-deficiency anemia, the most common type
- Thalassemia, an uncommon genetic condition
If your results show that your red blood cells are larger than normal, it may be a sign of:
- Pernicious anemia, which may be caused by:
  A lack of vitamin B12
  A disease that affects your body's ability to use vitamin B12, such as certain autoimmune diseases, celiac disease, or Crohn's disease.
- Anemia caused by a lack of folic acid
- Liver disease
It's also possible to have anemia with a normal MCV. This may happen if anemia is caused by conditions, such as:
- A sudden loss of blood
- Kidney failure
- Aplastic anemia (uncommon)
If your MCV levels are not in the normal range, it doesn't always mean that you have a medical problem that needs treatment. Diet, activity level, medicines, a menstrual period, and other conditions can affect the test results. Talk with your health care provider to learn what your results mean.
1. MCV (Mean Corpuscular Volume): MedlinePlus Medical Test [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 (22)

Microcytic, normocytic, and macrocytic anemias | NCLEX-RN | Khan Academy

Video by khanacademymedicine/YouTube

Non-megaloblastic Macrocytic Anemia

Video by Medicosis Perfectionalis/YouTube

Microcytic anemia | Hematologic System Diseases | NCLEX-RN | Khan Academy

Video by khanacademymedicine/YouTube

Living with and Managing Iron-Deficiency Anemia

Video by NHLBI/YouTube

Hemolytic Anemia

Video by DrER.tv/YouTube

Medical School - Anemia Made Easy

Video by iMedicalSchool/YouTube

Iron deficency anemia diagnosis | Hematologic System Diseases | NCLEX-RN | Khan Academy

Video by khanacademymedicine/YouTube

RBC Indices

Video by Pathology Simplified/YouTube

Anemia: Basic lab tests - hematocrit, hemoglobin, reticulocyte, MCV, morphology

Video by retic20/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

Blood Brain Barrier Endothelium

The blood-brain barrier keeps potentially toxic substances from entering the brain. The semipermeable membrane formed by the tightly spaced cells of capillaries in this area selectively screens out large molecules, while permitting the transport of essential nutrients such as glucose. The endothelium is the cellular lining of the blood vessel and is made up of endothelial cells connected to one another by tight junctions. These are the strongest cell-to-cell adhesions in the body. Toxic materials being transported in the blood are too large to pass through these junctions and exit the blood. Therefore, the brain is protected from exposure to many harmful substances. The barrier is does not, however, prevent fat-soluble materials from entering the brain; this includes alcohol and nicotine.

Image by TheVisualMD

Normal Blood Glucose Levels in Capillary

This image depicts a healthy capillary with normal glucose (pink) and insulin (yellow) levels. Capillaries, the smallest blood vessels in your body, are where nutrients are transferred from blood to cells, and waste from cells to blood. The body's cells depend on sugar in the blood, which is derived from carbohydrates, for food and energy. Allowing for the innumerable differences among individuals, the threshold for a normal blood-sugar (glucose) level in healthy people is 100 mg/dL; that is, 100 milligrams of glucose per deciliter of blood. Lower-than-normal levels characterize hypoglycemia and higher than normal levels characterize hyperglycemia.

Image by TheVisualMD

Cross-Section of Healthy Capillary Blood Vessel with Normal Glucose and Insulin Levels

This image depicts a healthy capillary. Capillaries are the smallest blood vessels in your body and are where the transfer of nutrients from blood to cells and wastes from cells to the blood takes place.The cells of the body depend on sugar in the blood, derived from carbohydrates, for food and energy. Allowing for the innumerable differences among individuals, the threshold for a normal blood-sugar (glucose) level in healthy people is 100 mg/dL; that is, 100 milligrams of glucose per deciliter of blood. Lower-than-normal levels characterize hypoglycemia and higher than normal levels hyperglycemia.

Image by TheVisualMD

Blood Vessels in the Brain

The Blood Brain Barrier and Astrocytes type 1

Image by Ben Brahim Mohammed

Cross-Section of Damaged Capillary Blood Vessel with Very High Glucose and Insulin Levels

This image depicts an unhealthy, damaged capillary with very high levels of insulin and glucose. Capillaries, the smallest blood vessels in your body, are where nutrients are transferred from blood to cells, and waste from cells to the blood The body's cells depend on sugar (glucose) in the blood, which is derived from carbohydrates, for food and energy. Without insulin, glucose is not able to enter cells to be used as fuel. Allowing for the innumerable differences among individuals, the threshold for a normal blood-sugar (glucose) level in healthy people is 100 mg/dL; that is, 100 milligrams of glucose per deciliter of blood. Higher than normal levels lead to hyperglycemia. Hyperglycemia is the hallmark of prediabetes (between 100 and 125 mg/dL) and diabetes (126 mg/dL and higher). It is caused by either too little insulin being released by the pancreas or the body's inability to use insulin properly. Hyperglycemia leads to microangiopathy, marked by endothelial cell apoptosis (programmed cell death), accumulation of AGEs (advanced glycation end products), and thickening of the basement membrane, which can lead to development of lesions, vasoconstriction, and altered vessel function

Blood Components

This image highlights the vital components of blood: 55% plasma Plasma is the liquid river that transports every blood cell to its destination. Oxygen-carrying RBCs couldn't move through arteries, veins and capillaries without it. Even though it is a watery, almost clear fluid, plasma contains many important substances, including blood-clotting agents called platelets and protective proteins called antibodies which help us fight infection. When the clotting agents are removed from blood plasma, it is called serum, which is essential in many life-saving medical situations such as transplant surgery and trauma. <1% white blood cells (wbcs or leukocytes) Some leukocytes are produced in the bone marrow, while others are generated in lymph nodes scattered throughout the body. They are far less numerous than their sister RBCs, but leukocytes are the bedrock of the immune system and are the body's front line of defense. Different types of leukocytes fight infections in different ways. Some target bacterial or fungal infections, while others respond to parasitic threats or allergic reactions. <1% platelets Platelets perform the vital function of clotting blood at wound sites. They are small, even in comparison to the other cells of your blood, but they pack a wallop when it comes to healing a scrape or staunching a more serious wound. When you cut yourself shaving, platelets arrive on the scene like your personal emergency medical team, creating a natural bandage of clotted blood, which eventually forms a scab. 45% red blood cells rbcs or erythrocytes) RBCs are produced in the bone marrow and perform the fundamental task of delivering oxygen to all of the body's cells. The vial is an example of the hematocrit, one of many tests that make up the complete blood count (CBC). Hematocrit measures the volume of RBCs in your blood. A normal hematocrit reading for women is between 36 to 44 percent; for men it's 41 to 50 percent.

Image by TheVisualMD

Test Tube Containing Blood

Visualization of a test tube containing blood. Blood comprises of 55% plasma, 1% platelets and white blood cells, and 45% red blood cells.

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

Healthy Capillary Blood Vessel

Cross-section of Healthy Capillary Blood Vessel with Normal Glucose and Insulin Levels

Cross-Section of Damaged Capillary Blood Vessel with Very High Glucose and Insulin Levels

1

2

3

Healthy Capillary Blood Vessel and and Damaged Capillary Blood Vessel Caused by High Levels of Blood Glucose

1) Healthy Capillary Blood Vessel - This image depicts a healthy capillary. Capillaries are the smallest blood vessels in your body. They can be so thin in diameter that blood cells have to bend in order to pass through. Capillaries are where the transfer of nutrients from the blood to cells, and the transfer of waste from cells to blood, takes place. In a healthy body, the blood vessels are smooth and elastic. 2) Cross-Section of Healthy Capillary Blood Vessel with Normal Glucose and Insulin Levels - This image depicts a healthy capillary. The body's cells depend on sugar in the blood, which is derived from carbohydrates, for food and energy. Allowing for the innumerable differences among individuals, the threshold for a normal blood sugar (glucose, pink) level in healthy people is 100 mg/dL; that is, 100 milligrams of glucose per deciliter of blood. Lower-than-normal levels characterize hypoglycemia and higher-than-normal levels characterize hyperglycemia. Without insulin (yellow), glucose is not able to enter cells to be used as fuel. Because of this, healthy insulin levels are a key factor in keeping blood glucose levels normal. 3) Cross-Section of Damaged Capillary Blood Vessel with Very High Glucose and Insulin Levels - This image depicts an unhealthy, damaged capillary with very high levels of insulin and glucose. Higher than normal levels of blood glucose lead to hyperglycemia. Hyperglycemia is the hallmark of prediabetes (between 100 and 125 mg/dL) and diabetes (126 mg/dL and higher). It is caused by either too little insulin being released by the pancreas or the body's inability to use insulin properly. Hyperglycemia leads to microangiopathy, marked by endothelial cell apoptosis (programmed cell death), accumulation of AGEs (advanced glycation end products), and thickening of the basement membrane, which can lead to the development of lesions, vasoconstriction, and altered vessel function

Interactive by TheVisualMD

5:57

Microcytic, normocytic, and macrocytic anemias | NCLEX-RN | Khan Academy

khanacademymedicine/YouTube

4:39

Non-megaloblastic Macrocytic Anemia

Medicosis Perfectionalis/YouTube

9:42

Microcytic anemia | Hematologic System Diseases | NCLEX-RN | Khan Academy

khanacademymedicine/YouTube

3:56

Living with and Managing Iron-Deficiency Anemia

NHLBI/YouTube

3:24

Hemolytic Anemia

DrER.tv/YouTube

3:16

Medical School - Anemia Made Easy

iMedicalSchool/YouTube

9:54

Iron deficency anemia diagnosis | Hematologic System Diseases | NCLEX-RN | Khan Academy

khanacademymedicine/YouTube

9:02

RBC Indices

Pathology Simplified/YouTube

4:32

Anemia: Basic lab tests - hematocrit, hemoglobin, reticulocyte, MCV, morphology

retic20/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

Blood Brain Barrier Endothelium

TheVisualMD

Normal Blood Glucose Levels in Capillary

TheVisualMD

Cross-Section of Healthy Capillary Blood Vessel with Normal Glucose and Insulin Levels

TheVisualMD

Blood Vessels in the Brain

Ben Brahim Mohammed

Cross-Section of Damaged Capillary Blood Vessel with Very High Glucose and Insulin Levels

Blood Components

TheVisualMD

Test Tube Containing Blood

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

Healthy Capillary Blood Vessel and and Damaged Capillary Blood Vessel Caused by High Levels of Blood Glucose

TheVisualMD

Partial Thromboplastin Time Test

Partial Thromboplastin Time Test

Also called: Activated Partial Thromboplastin Time, aPTT, Intrinsic Pathway Coagulation Factor Profile, PTT

A partial thromboplastin time (PTT) test measures the time it takes for a clot to form in a blood sample. It helps find bleeding and clotting disorders. A PTT test is often done with other tests that check clotting factors and how well they all work together.

Partial Thromboplastin Time Test

Also called: Activated Partial Thromboplastin Time, aPTT, Intrinsic Pathway Coagulation Factor Profile, PTT

A partial thromboplastin time (PTT) test measures the time it takes for a clot to form in a blood sample. It helps find bleeding and clotting disorders. A PTT test is often done with other tests that check clotting factors and how well they all work together.

{"label":"PTT Reference Range","scale":"lin","step":0.1,"hideunits":false,"units":[{"printSymbol":"s","code":"s","name":"second - time"}],"items":[{"flag":"abnormal","label":{"short":"Shortened","long":"Shortened","orientation":"horizontal"},"values":{"min":0,"max":25},"text":"This means that it took too little time for your blood to clot.","conditions":["Early stages of disseminated intravascular coagulation","Cancer (except in the liver)","Severe tissue inflammation or trauma","Errors when taking or processing the blood sample",""]},{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":25,"max":35},"text":"This is the normal time it takes for a blood clot to appear in case of injury. This range may slightly vary from laboratory to laboratory.","conditions":[]},{"flag":"abnormal","label":{"short":"Prolonged","long":"Prolonged","orientation":"horizontal"},"values":{"min":35,"max":100},"text":"A prolonged PTT time result indicates a bleeding disorder, and it means that there are not enough clotting factors or they are not functioning properly. ","conditions":["Blood thinners intake","Liver disease","Malabsorption","Low level of vitamin K","Bleeding disorders","Insufficiency of one or more proteins involved in the coagulation cascade","Disseminated intravascular coagulation"]}],"value":30}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
s
25
35
Your result is Normal.
This is the normal time it takes for a blood clot to appear in case of injury. This range may slightly vary from laboratory to laboratory.
Related conditions
A partial thromboplastin time (PTT) test uses a blood sample to measure how long it takes for your blood to make a clot. Normally, when you get a cut or injury that causes bleeding, many different types of proteins in your blood work together to make a clot to stop the bleeding. These proteins are called coagulation factors or clotting factors.
If any of your clotting factors are missing, at a low level, or not working properly, your blood may:
- Clot too slowly after an injury or surgery. If this happens, you have a bleeding disorder. Bleeding disorders can cause serious blood loss. Hemophilia is one type of bleeding disorder.
- Clot too much and/or too quickly, even without an injury. This condition may lead to clots that block your blood flow and cause serious conditions, such as heart attack, stroke, or clots in the lungs.
A PTT test helps check a specific group of clotting factors. It helps show how much of these clotting factors you have and how well they're working. A PTT test is often done with other tests that check clotting factors and how well they all work together.
A PTT test is used to check for problems with a specific group of blood clotting factors. The test is done to:
- Find the cause of too much bruising or bleeding.
- Find the cause of clotting problems. Causes can include certain autoimmune diseases such as lupus and antiphospholipid syndrome (APS).
- Monitor people taking heparin, a type of medicine that's used to prevent and treat blood clots. PTT testing can help make sure the dose is safe and effective.
- Check the risk for possible bleeding problems before surgery or medical procedures. (A PTT test is not always used as a routine test before surgery. It may be used for certain people who may have a risk for bleeding problems).
You may need a PTT test if you:
- Have problems with bleeding or bruising and the cause is not known
- Have a blood clot in a vein or artery
- Have liver disease (your liver makes most of your clotting factors).
- Have had several miscarriages
- Have been diagnosed with a bleeding or clotting disorder and don't know which clotting factors are involved
- Are taking heparin (to check how this medicine is affecting you, your health care provider may use a PTT test or another test instead).
Your PTT test results will show how much time it took for your blood to clot. Results are usually given as a number of seconds. A PTT test is often ordered along with another blood test called a prothrombin time (PT) test. A PT test measures other clotting factors that a PTT test doesn't check. Your provider will usually compare the results of both tests to understand how your blood is clotting. Ask your provider to explain what your test results mean for your health.
In general, if your blood took longer than normal to clot on a PTT test, it may be a sign of:
- Liver disease.
- A lack of vitamin K.
- Certain genetic disorders that you inherit from your parents. These disorders affect certain clotting factors and increase your risk of bleeding. They include:
  Von Willebrand disease.
  Hemophilia.
- Too much heparin.
- Certain types of leukemia.
- Autoimmune diseases, such as antiphospholipid antibody syndrome or lupus anticoagulant syndrome. These diseases cause your body to make proteins called antibodies. The antibodies related to these diseases cause too much clotting. But the results of a PTT test may show a slow clotting time. That's because the chemicals in the PTT test react with the antibodies in your blood sample. This chemical reaction makes the blood sample clot more slowly than the blood in your body. If your provider thinks that an autoimmune disease is causing a clotting problem, you will usually have other tests to make a diagnosis.
If your blood clotted faster than normal on a PTT test, it may be a sign of:
- The early stage of disseminated intravascular coagulation (DIC). This rare but serious condition may develop if you have an infection or damage to organs or tissues that affects blood clotting. In the early stage, you have too much blood clotting. Later on, DIC starts to use up clotting factors in your blood, which leads to bleeding problems.
- Cancer of the ovaries, colon, or pancreas that is advanced, which means the cancer has spread to other parts of the body and is unlikely to be controlled with treatment.
Talk with your provider to learn what your test results mean.
1. Partial Thromboplastin Time (PTT) Test: MedlinePlus Medical Test [accessed on Dec 20, 2022]
2. Partial thromboplastin time (PTT): MedlinePlus Medical Encyclopedia [accessed on Sep 29, 2018]
3. PTT [accessed on Sep 29, 2018]
4. APTTP - Clinical: Activated Partial Thromboplastin Time (APTT), Plasma [accessed on Sep 29, 2018]
5. 005207: Partial Thromboplastin Time (PTT), Activated | LabCorp [accessed on Sep 29, 2018]

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 (15)

Activated Partial Thromboplastin Time Nursing Considerations, Normal Range, Nursing Care

Video by NURSINGcom/YouTube

Hemarthrosis - Bleeding into the joints. It may arise from trauma or spontaneously in patients with hemophilia.

Hemarthrosis Medical X-rays.

Image by Nevit Dilmen (talk)

Hemarthrosis

Hemarthrosis Medical X-rays.

Image by Nevit Dilmen (talk)

Prothrombin Time (PT): Pulmonary Embolism

The most dangerous complication of deep vein thrombosis (DVT) is pulmonary embolism, which occurs when an embolism travels through the heart and into the lungs. There it lodges in an artery, typically where the artery forks, and blocks blood flow. During an episode of pulmonary embolism, the lungs may be showered with blood clots. The lungs are particularly vulnerable to embolisms because all the blood in the body passes through the lungs every time it circulates.

Image by TheVisualMD

Prothrombin Time (PT): Pulmonary Embolism

The most dangerous complication of deep vein thrombosis (DVT) is pulmonary embolism, which occurs when an embolism travels through the heart and into the lungs. There it lodges in an artery, typically where the artery forks, and blocks blood flow. During an episode of pulmonary embolism, the lungs may be showered with blood clots. The lungs are particularly vulnerable to embolisms because all the blood in the body passes through the lungs every time it circulates.

Image by TheVisualMD

Coagulopathy

Trauma triad of death

Image by en:User:Cburnett

The image shows one example of how the hemophilia gene is inherited.

The image shows one example of how the hemophilia gene is inherited. In this example, the father has hemophilia (that is, his X chromosome is faulty). The mother isn't a hemophilia carrier (that is, she has two normal X chromosomes). Each daughter will inherit the faulty gene from her father and be a carrier. None of the sons will inherit the faulty gene from their father; thus, none will have hemophilia.

Image by National Heart Lung and Blood Institute (NIH)

Hemophilia - blood clotting factors

Drawing the mixed Antihemophilic Factor / Sterile Saline into syringes for injection. Jacob recieves 7 syringes each Friday. What is Hemophilia? Blood clotting, or coagulation, is the process that controls bleeding. It changes blood from a liquid to a solid. It's a complex process involving as many as 20 different plasma proteins, or blood clotting factors. Normally, a complex chemical process occurs using these clotting factors to form a substance called fibrin that stops bleeding. When certain coagulation factors are deficient or missing, the process doesn't occur normally. In people with bleeding disorders, clotting factors are missing or don't work as they should. This causes them to bleed for a longer time, bruise easier and have greater joint pain than those whose blood factor levels are normal.

Image by Jkgroove

Blood clots

This medical illustration reveals how the SHELTERTM device traps and removes blood clots in the brain.

Image by Zina Deretsky, NSF

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels.

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue. - Wikipedia

Image by MarinaVladivostok

Blood clots

Red blood cells trapped in a fibrin network in a blood clot.

Image by Fuzis

Blood Clot

Image by Mark Ellisman and Thomas Deerinck National Center for Microscopy and Imaging Research University of California, San Diego

Sensitive content

This media may include sensitive content

Platelet Disorders

From left to right: erythrocyte, thrombocyte, leukocyte

Image by Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)

Platelet Disorders

Platelets by budding off from megakaryocytes

Hemarthrosis

Lipohemarthrosis (blood and fat in the joint space) seen in a person with a subtle tibial plateau fracture. The arrow indicates a fluid level between the upper fat component and the lower blood component.

Image by James Heilman, MD

3:15

Activated Partial Thromboplastin Time Nursing Considerations, Normal Range, Nursing Care

NURSINGcom/YouTube

Hemarthrosis - Bleeding into the joints. It may arise from trauma or spontaneously in patients with hemophilia.

Nevit Dilmen (talk)

Hemarthrosis

Nevit Dilmen (talk)

Prothrombin Time (PT): Pulmonary Embolism

TheVisualMD

Prothrombin Time (PT): Pulmonary Embolism

TheVisualMD

Coagulopathy

en:User:Cburnett

The image shows one example of how the hemophilia gene is inherited.

National Heart Lung and Blood Institute (NIH)

Hemophilia - blood clotting factors

Jkgroove

Blood clots

Zina Deretsky, NSF

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels.

MarinaVladivostok

Blood clots

Fuzis

Blood Clot

Mark Ellisman and Thomas Deerinck National Center for Microscopy and Imaging Research University of California, San Diego

Sensitive content

This media may include sensitive content

Platelet Disorders

Electron Microscopy Facility at The National Cancer Institute at Frederick (NCI-Frederick)

Platelet Disorders

Hemarthrosis

James Heilman, MD

Prothrombin Time and INR Test

Prothrombin Time Test and INR

Also called: PT/INR, Prothrombin Time, Prothrombin Time/International Normalized Ratio, PT Protime

A prothrombin time test (PT) measures the time it takes for a clot to form in a blood sample. An INR is a calculation based on the results of a PT test. A PT/INR test is used to see if your blood is clotting normally and if warfarin is effective in treating clotting disorders.

Prothrombin Time Test and INR

Also called: PT/INR, Prothrombin Time, Prothrombin Time/International Normalized Ratio, PT Protime

A prothrombin time test (PT) measures the time it takes for a clot to form in a blood sample. An INR is a calculation based on the results of a PT test. A PT/INR test is used to see if your blood is clotting normally and if warfarin is effective in treating clotting disorders.

{"label":"Prothrombin time reference range","scale":"lin","step":0.1,"hideunits":false,"items":[{"flag":"abnormal","label":{"short":"Shortened","long":"Shortened","orientation":"horizontal"},"values":{"min":0,"max":11},"text":"Shortened PT results refer to a \u201cthick blood,\u201d which means that blood clots form easily in the blood.","conditions":["Early stages of disseminated intravascular coagulation","Cancer (except in the liver)","Severe tissue inflammation or trauma","Errors when taking or processing the blood sample"]},{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":11,"max":13.5},"text":"The average time range for blood to clot is about 11 to 13.5 seconds. If you are taking blood thinning drugs, your results should be interpreted using the international normalized ratio (INR).","conditions":[]},{"flag":"abnormal","label":{"short":"Prolonged","long":"Prolonged","orientation":"horizontal"},"values":{"min":13.5,"max":25},"text":"A prolonged PT result means that the blood is taking too long to form a clot. This may indicate excessive blood thinning.","conditions":["Intake of blood thinners (such as warfarin)","Bleeding disorders","Liver disease","Low level of vitamin K","Insufficiency of one or more proteins involved in the coagulation cascade","Disseminated intravascular coagulation"]}],"units":[{"printSymbol":"s","code":"s","name":"second - time"}],"value":12.3}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
s
11
13.5
Your result is Normal.
The average time range for blood to clot is about 11 to 13.5 seconds. If you are taking blood thinning drugs, your results should be interpreted using the international normalized ratio (INR).
Related conditions
{"label":"INR reference range","scale":"lin","step":0.1,"hideunits":false,"items":[{"flag":"abnormal","label":{"short":"Low","long":"Low","orientation":"horizontal"},"values":{"min":0,"max":2},"text":"If the INR is below the target range there is an increased risk of clotting. The dose of blood thinner may be increased to get the PT\/INR blood test into the correct range.","conditions":["Early stages of disseminated intravascular coagulation","Cancer (except in the liver)","Severe tissue inflammation or trauma","Errors when taking or processing the blood sample"]},{"flag":"normal","label":{"short":"Optimal","long":"Optimal","orientation":"horizontal"},"values":{"min":2,"max":3},"text":"The target (optimal therapeutic) INR range depends on why you are taking the blood thinner. In most cases the target INR range will be between 2 and 3, although other ranges may be chosen if there are special circumstances.","conditions":[]},{"flag":"abnormal","label":{"short":"High","long":"High","orientation":"horizontal"},"values":{"min":3,"max":6},"text":"If the INR is above the target range there is an increased risk of uncontrolled or dangerous bleeding. Close monitoring is needed until the risk of bleeding is reduced. The dose of blood thinner may be lowered to get the PT\/INR blood test into the correct range.","conditions":["Bleeding disorders","Liver disease","Low level of vitamin K","Insufficiency of one or more proteins involved in the coagulation cascade","Disseminated intravascular coagulation"]}],"units":[{"printSymbol":"{INR}","code":"{INR}","name":"international normalized ratio"}],"value":2.5}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
{INR}
2
3
Your result is Optimal.
The target (optimal therapeutic) INR range depends on why you are taking the blood thinner. In most cases the target INR range will be between 2 and 3, although other ranges may be chosen if there are special circumstances.
Related conditions
A PT/INR test is most often used to:
- See how well warfarin is working. Warfarin is a blood-thinning medicine that's used to treat and prevent dangerous blood clots. (Coumadin is a common brand name for warfarin.)
- Find out the reason for abnormal blood clots
- Find out the reason for unusual bleeding
- Check clotting function before surgery
- Check for liver problems
A PT/INR test is often done along with a partial thromboplastin time (PTT) test. A PTT test also checks for clotting problems.
You may need this test if you are taking warfarin on a regular basis. The test helps make sure you are taking the right dose.
If you are not taking warfarin, you may need this test if you have symptoms of a bleeding or clotting disorder.
Symptoms of a bleeding disorder include:
- Unexplained heavy bleeding
- Bruising easily
- Unusually heavy nose bleeds
- Unusually heavy menstrual periods in women
Symptoms of a clotting disorder include:
- Leg pain or tenderness
- Leg swelling
- Redness or red streaks on the legs
- Trouble breathing
- Cough
- Chest pain
- Rapid heartbeat
In addition, you may need a PT/INR test if you are scheduled for surgery. It helps make sure your blood is clotting normally, so you won't lose too much blood during the procedure.
The test may be done on a blood sample from a vein or a fingertip.
For a blood sample from a vein:
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.
For a blood sample from a fingertip:
A fingertip test may be done in a provider's office or in your home. If you are taking warfarin, your provider may recommend you test your blood regularly using an at-home PT/INR test kit. During this test, you or your provider will:
- Use a small needle to puncture your fingertip
- Collect a drop of blood and place it onto a test strip or other special instrument
- Place the instrument or test strip into a device that calculates the results. At-home devices are small and lightweight.
If you are using an at-home test kit, you will need to review your results with your provider. Your provider will let you know how he or she would like to receive the results.
If you were tested because you are taking warfarin, your results will probably be in the form of INR levels. INR levels are often used because they make it easier to compare results from different labs and different test methods. If you are not taking warfarin, your results may be in the form of INR levels or the number of seconds it takes for your blood sample to clot (prothrombin time).
If you are taking warfarin:
- INR levels that are too low may mean you are at risk for dangerous blood clots.
- INR levels that are too high may mean you are at risk for dangerous bleeding.
Your health care provider will probably change your dose of warfarin to reduce these risks.
If you are not taking warfarin and your INR or prothrombin time results were not normal, it may mean one of the following conditions:
- A bleeding disorder, a condition in which the body can't clot blood properly, causing excessive bleeding
- A clotting disorder, a condition in which the body forms excessive clots in arteries or veins
- Liver disease
- Vitamin K deficiency. Vitamin K plays an important role in blood clotting.
Sometimes certain liver tests are ordered along with a PT/INR test. These include:
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
1. Prothrombin Time Test and INR (PT/INR): MedlinePlus Medical Test [accessed on Mar 06, 2024]
2. Prothrombin time (PT): MedlinePlus Medical Encyclopedia [accessed on Mar 06, 2024]
3. PT/INR Test (Prothrombin Time and International Normalized Ratio) - Testing.com. Nov 9, 2021 [accessed on Mar 06, 2024]
4. Patient education: Warfarin (Beyond the Basics). UpToDate [accessed on Mar 06, 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 (10)

Prothrombin Time (PT): Pulmonary Embolism

The most dangerous complication of deep vein thrombosis (DVT) is pulmonary embolism, which occurs when an embolism travels through the heart and into the lungs. There it lodges in an artery, typically where the artery forks, and blocks blood flow. During an episode of pulmonary embolism, the lungs may be showered with blood clots. The lungs are particularly vulnerable to embolisms because all the blood in the body passes through the lungs every time it circulates.

Image by TheVisualMD

Blood clots

This medical illustration reveals how the SHELTERTM device traps and removes blood clots in the brain.

Image by Zina Deretsky, NSF

Blood clots

Red blood cells trapped in a fibrin network in a blood clot.

Image by Fuzis

Factors V, VII, KIF6: Thrombosis

Thrombosis is the formation of a blood clot inside a blood vessel. If the clot is large or persistent enough, it can obstruct blood flow, which can starve tissue or entire organs of oxygen-carrying blood. Most strokes are the result of thrombosis.

Image by TheVisualMD

Platelets: Thrombus Formation

Thrombosis is the formation of a blood clot (thrombus) inside a blood vessel. If the clot is large or persistent enough, it can obstruct blood flow, which can starve tissue of oxygen-carrying blood. Most strokes are the result of thrombosis.

Image by TheVisualMD

Skin Cross Section with Razor Cut

When the skin is injured an inflammatory response is triggered to rid the body of harmful invaders. To begin this response mast cells and basophils secrete chemical signals that promote blood flow to the area.

Image by TheVisualMD

INR Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing

Video by NURSINGcom/YouTube

How to interpret a prothrombin time (PT) test

Video by Medmastery/YouTube

Coagulation Tests (PT, aPTT, TT, Fibrinogen, Mixing Studies,..etc)

Video by Medicosis Perfectionalis/YouTube

Prothrombin Time and Activated Prothrombin Time

Video by LabsforLifeProject/YouTube

Prothrombin Time (PT): Pulmonary Embolism

TheVisualMD

Blood clots

Zina Deretsky, NSF

Blood clots

Fuzis

Factors V, VII, KIF6: Thrombosis

TheVisualMD

Platelets: Thrombus Formation

TheVisualMD

Skin Cross Section with Razor Cut

TheVisualMD

3:41

INR Nursing Considerations, Normal Range, Nursing Care, Lab Values Nursing

NURSINGcom/YouTube

4:25

How to interpret a prothrombin time (PT) test

Medmastery/YouTube

19:22

Coagulation Tests (PT, aPTT, TT, Fibrinogen, Mixing Studies,..etc)

Medicosis Perfectionalis/YouTube

30:28

Prothrombin Time and Activated Prothrombin Time

LabsforLifeProject/YouTube

Fibrinogen Test

Fibrinogen Test

Also called: Coagulation Factor I, Factor I, Hypofibrinogenemia test

Fibrinogen, also called coagulation factor I, is a protein produced by the liver. When bleeding is detected in the body, fibrinogen is released along with other coagulation factors to form blood clots and stop the bleeding. Too much or too little fibrinogen can lead to serious health problems.

Fibrinogen Test

Also called: Coagulation Factor I, Factor I, Hypofibrinogenemia test

Fibrinogen, also called coagulation factor I, is a protein produced by the liver. When bleeding is detected in the body, fibrinogen is released along with other coagulation factors to form blood clots and stop the bleeding. Too much or too little fibrinogen can lead to serious health problems.

{"label":"Fibrinogen Reference Range","scale":"lin","step":0.1,"hideunits":false,"units":[{"printSymbol":"mg\/dL","code":"mg\/dL","name":"milligram per deciliter"}],"items":[{"flag":"abnormal","label":{"short":"Low","long":"Low","orientation":"horizontal"},"values":{"min":0,"max":200},"text":"Low fibrinogen levels can cause excessive or prolonged bleeding.","conditions":["Disseminated intravascular coagulation (DIC)","Advanced liver disease","Severe malnutrition","Blood clotting problems","Recent blood transfusion","Fibrinogen deficiency"]},{"flag":"normal","label":{"short":"Normal","long":"Normal","orientation":"horizontal"},"values":{"min":200,"max":400},"text":"Normal results may slightly vary based on the laboratory and the method used.","conditions":[]},{"flag":"abnormal","label":{"short":"High","long":"High","orientation":"horizontal"},"values":{"min":400,"max":1000},"text":"High levels of fibrinogen can cause the blood-clotting proteins to become overactive, leading to the formation of blood clots throughout the body\u2019s vessels; this prevents blood and oxygen to reach the tissues and organs, which can eventually cause organ failure. ","conditions":["Kidney disease","Liver disease","Cirrhosis","Inflammatory conditions","Infection","Diabetes","Pregnancy\u00a0","Disseminated intravascular coagulation (DIC)"]}],"value":300}[{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
mg/dL
200
400
Your result is Normal.
Normal results may slightly vary based on the laboratory and the method used.
Related conditions
Your doctor may want to order this test if you have signs or symptoms related to bleeding disorders or abnormal blood clotting. Other situations in which this test is ordered may include:
- Abnormal results on other blood tests known as PTT (partial thromboplastin time), PT (prothrombin time), or TCT (thrombin clotting time).
- If you have signs or symptoms of a disorder called disseminated intravascular coagulation (DIC), which is a serious and potentially life-threatening condition in which excessive clotting and bleeding can occur at the same time.
- As part of screening tests for liver disease.
- When you are taking medicine to prevent blood clots, to monitor the treatment effectiveness.
- If a close family member has been diagnosed with a disorder known as factor I deficiency.
You should visit your doctor if you experience any of the following:
- Nosebleeds
- Bleeding gums or rectum
- Bruises of unknown origin
- A skin rash with small red or purple dots
- Heavy menstrual bleeding
- Blood in the stools or urine
- Bleeding from wounds that do not stop on its own, or that take too much time to heal
- Frequent headaches
- Chest pain
- Temporary vision changes
- Fainting
- Dizziness
- Numbness or tingling in your hands and feet
Low fibrinogen levels can cause excessive or prolonged bleeding, due to:
- Disseminated intravascular coagulation (DIC)
- Advanced liver disease
- Severe malnutrition
- Blood clotting problems
- Recent blood transfusion
- Factor I deficiency, which is a rare inherited (passed from parent to child) disorder that could include either afibrinogenemia (complete absence of fibrinogen) or hypofibrinogenemia (low fibrinogen levels)
High levels of fibrinogen can cause the blood-clotting proteins to become overactive, leading to the formation of blood clots throughout the body’s vessels; this prevents blood and oxygen to reach the tissues and organs, which can eventually cause organ failure.
High results may be due to:
- Kidney disease
- Liver disease
- Cirrhosis (liver scarring)
- Inflammatory conditions, such as rheumatoid arthritis
- Infection
- Diabetes
- Pregnancy
- Disseminated intravascular coagulation (DIC)
1. Fibrinogen [accessed on Oct 03, 2018]
2. Fibrinogen: Reference Range, Interpretation, Collection and Panels [accessed on Oct 03, 2018]
3. Factor I - Health Encyclopedia - University of Rochester Medical Center [accessed on Oct 03, 2018]
4. FIBTP - Clinical: Fibrinogen, Plasma [accessed on Oct 03, 2018]
5. Fibrinogen blood test: MedlinePlus Medical Encyclopedia [accessed on Oct 03, 2018]

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 (6)

Fibrinogen

Crystal structure of native chicken fibrinogen with two different bound ligands

Image by Jawahar Swaminathan and MSD staff at the European Bioinformatics Institute

Blood clots

Red blood cells trapped in a fibrin network in a blood clot.

Image by Fuzis

Blood clots

This medical illustration reveals how the SHELTERTM device traps and removes blood clots in the brain.

Image by Zina Deretsky, NSF

Coagulation cascade

Video by FerrosanMD/YouTube

How does a blood clot pass from the leg to the lung? Anatomy.

Video by Sam Webster/YouTube

How Blood Clots Form

Video by Vascular Cures/YouTube

Fibrinogen

Jawahar Swaminathan and MSD staff at the European Bioinformatics Institute

Blood clots

Fuzis

Blood clots

Zina Deretsky, NSF

4:51

Coagulation cascade

FerrosanMD/YouTube

14:44

How does a blood clot pass from the leg to the lung? Anatomy.

Sam Webster/YouTube

3:56

How Blood Clots Form

Vascular Cures/YouTube

Factor VIII Test

Factor VIII Test

Also called: Antihemophilia Factor A, Hemophilic factor A, Coagulation factor VIII

When a wound occurs in any part of the body, several factors (proteins) which are involved in the normal blood clotting process become active to stop the bleeding. This test is used to measure the activity of the coagulation factor VIII, which is one of the proteins that help your blood to clot. This is useful to diagnose a condition known as hemophilia A.

Factor VIII Test

Also called: Antihemophilia Factor A, Hemophilic factor A, Coagulation factor VIII

When a wound occurs in any part of the body, several factors (proteins) which are involved in the normal blood clotting process become active to stop the bleeding. This test is used to measure the activity of the coagulation factor VIII, which is one of the proteins that help your blood to clot. This is useful to diagnose a condition known as hemophilia A.

{"label":"Factor VIII Reference Range","scale":"lin","step":0.1,"hideunits":false,"units":[{"printSymbol":"%","code":"%","name":"percent"}],"items":[{"flag":"abnormal","label":{"short":"SL","long":"Severely low","orientation":"horizontal"},"values":{"min":0,"max":1},"text":"Your factor VIII results are severely decreased. This is highly indicative of hemophilia A. ","conditions":["Severe hemophilia A","Bleeding disorders","Von Willebrand disease","Disseminated intravascular coagulation\u00a0","Presence of a Factor VIII inhibitor",""]},{"flag":"abnormal","label":{"short":"ML","long":"Moderately low","orientation":"horizontal"},"values":{"min":1,"max":5},"text":"Your factor VIII results are moderately decreased. This is indicative of hemophilia A. ","conditions":["Moderate hemophilia A","Bleeding disorders","Von Willebrand disease","Disseminated intravascular coagulation\u00a0","Presence of a Factor VIII inhibitor"]},{"flag":"abnormal","label":{"short":"ML","long":"Mildly low","orientation":"horizontal"},"values":{"min":5,"max":50},"text":"Your factor VIII results are mildly decreased. This is suggestive of hemophilia A. ","conditions":["Mild hemophilia A","Bleeding disorders","Von Willebrand disease","Disseminated intravascular coagulation\u00a0","Presence of a Factor VIII inhibitor"]},{"flag":"normal","label":{"short":"N","long":"Normal","orientation":"horizontal"},"values":{"min":50,"max":150},"text":"Normal results vary based on the laboratory and the method used.","conditions":[]},{"flag":"abnormal","label":{"short":"H","long":"High","orientation":"horizontal"},"values":{"min":150,"max":200},"text":"Your factor VIII results are elevated. Talk to your doctor to know what this means in your specific case. ","conditions":["Liver disease","Inflammation","Diabetes","Pregnancy","Obesity","Older age"]}],"value":100}[{"abnormal":2},{"abnormal":1},{"abnormal":0},{"normal":0},{"abnormal":0}]
Use the slider below to see how your results affect your health.
%
1
5
50
150
Your result is Normal.
Normal results vary based on the laboratory and the method used.
Related conditions
Your doctor may want to order this test to diagnose a condition known as hemophilia A, also called coagulation factor VIII deficiency, in the following situations:
- When previous test results, such as prothrombin time (PT) and/or partial thromboplastin time (PTT), have shown that your blood is not clotting properly.
- As part of an evaluation for a bleeding disorder called von Willebrand disease.
- When one of your family members is known to have hemophilia A.
- To assess the response to hemophilia A treatment.
You should visit your doctor if you experience any of the following signs and symptoms:
- Bruises of unknown origin
- Nosebleeds
- Heavy menstrual bleeding
- Bleeding gums or rectum
- A skin rash with small red or purple dots
- Blood in the stools or urine
- Wounds that do not stop bleeding on its own, or that take too much time to heal
- Frequent headaches
- Chest pain
- Temporary vision changes
Normal factor VIII activity results are 50% to 150%. However, this test results can vary depending on your gender, age, clinical history, other test results, and the method used for testing.
Factor VIII results below 50% are highly indicative of hemophilia A.
A result between 5% to 50% indicates mild hemophilia A; while a result from 1% to 5% suggests moderate hemophilia A. People who have less than 1% usually suffer from severe hemophilia A.
Decreased factor VIII activity may be due to:
- Hemophilia A
- Von Willebrand disease (another type of bleeding disorder)
- Disseminated intravascular coagulation (excessive activity of the proteins that control blood clotting)
- Presence of a Factor VIII inhibitor (antibody)
Increased factor VIII activity may be due to:
- Liver disease
- Inflammation
- Diabetes
- Pregnancy
- Obesity
- Older age
Ask your doctor what your test results mean in your specific case.
1. Factor VIII assay: MedlinePlus Medical Encyclopedia [accessed on Oct 02, 2018]
2. Blood Test: Factor VIII Activity (for Parents) [accessed on Oct 02, 2018]
3. 086264: Factor VIII Activity | LabCorp [accessed on Oct 02, 2018]
4. Factor VIII (Antihemophilic Factor A) - Health Encyclopedia - University of Rochester Medical Center [accessed on Oct 02, 2018]
5. F8A - Clinical: Coagulation Factor VIII Activity Assay, Plasma [accessed on Oct 30, 2018]
6. Coagulation Factors [accessed on Oct 30, 2018]

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)

Beyond Diagnosis: Treatment Options and Resources for People with Inhibitors

This fact sheet contains information about treatment options for inhibitors and provides resources for people have been diagnosed with an inhibitor or would like to learn more on the subject.

Document by Centers for Disease Control and Prevention (CDC)

Platelet Development

Illustration of Platelet Development

Image by OpenStax College

Sensitive content

This media may include sensitive content

Bleeding

Bleeding, technically known as hemorrhaging or hemorrhaging - Bleeding wound on finger

Image by Crystal (Crystl) from Bloomington, USA

Factors V and VII, Cutting of Skin

When the skin is cut, a cascade of reactions takes place almost immediately in order to stanch the flow of blood and lay the groundwork for healing. Platelets are cell fragments produced in the bone marrow that essential to the process of blood clotting. In addition to platelets, there are more than a dozen different blood-clotting factors that interact in the process of blood clotting; even the absence or malfunction of just one of these factors, can disrupt this process and lead to serious illness, such as hemophilia.

Image by TheVisualMD

Hemophilia

Hemophilia is an inherited disease, most commonly affecting males, that is characterized by a deficiency in blood clotting.

Image by National Human Genome Research Institute (NHGRI)

The image shows one example of how the hemophilia gene is inherited.

In this example, the father doesn't have hemophilia (that is, he has two normal chromosomes-X and Y). The mother is a carrier of hemophilia (that is, she has one faulty X chromosome and one normal X chromosome). Each daughter has a 50 percent chance of inheriting the faulty gene from her mother and being a carrier. Each son has a 50 percent chance of inheriting the faulty gene from his mother and having hemophilia.

Image by National Heart Lung and Blood Institute (NIH)

Inheritance pattern for hemophilia in which the mother is a carrier

In this example, the father does not have hemophilia. He has two normal chromosomes, X and Y. The mother is a carrier of hemophilia, because she has one hemophilia gene on one X chromosome and one normal X chromosome. Each daughter has a 50% chance of inheriting the hemophilia gene from her mother and being a carrier. Each son has a 50% chance of having hemophilia.

Image by National Heart, Lung, and Blood Institute (NHLBI)

Hemophilia - blood clotting factors

Drawing the mixed Antihemophilic Factor / Sterile Saline into syringes for injection. Jacob recieves 7 syringes each Friday. What is Hemophilia? Blood clotting, or coagulation, is the process that controls bleeding. It changes blood from a liquid to a solid. It's a complex process involving as many as 20 different plasma proteins, or blood clotting factors. Normally, a complex chemical process occurs using these clotting factors to form a substance called fibrin that stops bleeding. When certain coagulation factors are deficient or missing, the process doesn't occur normally. In people with bleeding disorders, clotting factors are missing or don't work as they should. This causes them to bleed for a longer time, bruise easier and have greater joint pain than those whose blood factor levels are normal.

Image by Jkgroove

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels.

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue. - Wikipedia

Image by MarinaVladivostok

3d ribbon/surface model of the human factor VIII

"Crystal structure of human factor VIII: implications for the formation of the factor IXa-factor VIIIa complex"

Image by Ayacop

Hemarthrosis

Lipohemarthrosis (blood and fat in the joint space) seen in a person with a subtle tibial plateau fracture. The arrow indicates a fluid level between the upper fat component and the lower blood component.

Image by James Heilman, MD

Inheritance pattern for hemophilia in which the father has hemophilia

In this example, the mother is not a hemophilia carrier and has two normal X chromosomes. None of the children will have hemophilia. Each daughter will inherit the hemophilia gene from her father and be a carrier.

Image by National Heart, Lung, and Blood Institute (NHLBI)

Hemarthrosis - Bleeding into the joints. It may arise from trauma or spontaneously in patients with hemophilia.

Hemarthrosis Medical X-rays.

Image by Nevit Dilmen (talk)

Hemarthrosis

Hemarthrosis Medical X-rays.

Image by Nevit Dilmen (talk)

Scheme of a blood sample after centrifugation

scheme of a blood sample after centrifugation

Image by KnuteKnudsen (talk)

Platelet Disorders

Platelets by budding off from megakaryocytes

Blood fractionation

Vial of separated blood. The middle layer is a type of sterile goo which separates the blood from the rest of what's drawn.

Image by Wheeler Cowperthwaite from Reno, USA

Beyond Diagnosis: Treatment Options and Resources for People with Inhibitors

Centers for Disease Control and Prevention (CDC)

Platelet Development

OpenStax College

Sensitive content

This media may include sensitive content

Bleeding

Crystal (Crystl) from Bloomington, USA

Factors V and VII, Cutting of Skin

TheVisualMD

Hemophilia

National Human Genome Research Institute (NHGRI)

The image shows one example of how the hemophilia gene is inherited.

National Heart Lung and Blood Institute (NIH)

Inheritance pattern for hemophilia in which the mother is a carrier

National Heart, Lung, and Blood Institute (NHLBI)

Hemophilia - blood clotting factors

Jkgroove

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels.

MarinaVladivostok

3d ribbon/surface model of the human factor VIII

Ayacop

Hemarthrosis

James Heilman, MD

Inheritance pattern for hemophilia in which the father has hemophilia

National Heart, Lung, and Blood Institute (NHLBI)

Hemarthrosis - Bleeding into the joints. It may arise from trauma or spontaneously in patients with hemophilia.

Nevit Dilmen (talk)

Hemarthrosis

Nevit Dilmen (talk)

Scheme of a blood sample after centrifugation

KnuteKnudsen (talk)

Platelet Disorders

Blood fractionation

Wheeler Cowperthwaite from Reno, USA

Von Willebrand Factor Activity Test

Von Willebrand Factor Activity Test

Also called: vWF Activity, von Willebrand Factor Activity - Ristocetin Cofactor, vWF Activity Ristocetin Cofactor, vWF RCo

When a wound occurs in any part of the body, several factors (proteins) which are involved in the normal blood clotting process become active to stop the bleeding; one of these factors is the von Willebrand factor (vWF). Decreased levels of vWF are suggestive of von Willebrand disease (VWD), which is the most common inherited bleeding disorder. This...

Von Willebrand Factor Activity Test

Also called: vWF Activity, von Willebrand Factor Activity - Ristocetin Cofactor, vWF Activity Ristocetin Cofactor, vWF RCo

When a wound occurs in any part of the body, several factors (proteins) which are involved in the normal blood clotting process become active to stop the bleeding; one of these factors is the von Willebrand factor (vWF). Decreased levels of vWF are suggestive of von Willebrand disease (VWD), which is the most common inherited bleeding disorder. This...

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Use the slider below to see how your results affect your health.
%
50
150
Your result is Normal.
Normal vWF activity (Ristocetin Cofactor) concentrations can vary depending on the person’s blood type and on the method used for testing by the laboratory.
Related conditions
The von Willebrand disease (VWD) is a condition that causes the blood to not clot properly due to deficient and/or defective von Willebrand factor. This puts the affected person at risk of uncontrolled bleeding.
VWD is the most common inherited bleeding disorder, which means that is usually transmitted from parents to children. Although, it can also occur spontaneously.
This disease has several variations that range from mild to severe:
- Type 1: too little of the vWF is present in your blood. This is the mildest and most common form of the disease.
- Type 2: you have normal vWF levels, but the protein is defective. Bleeding may be more severe with this form of the disease. Type 2 VWD is further divided into several subtypes.
- Type 3: your vWF is completely missing. This is the rarest form of the disease, and it’s usually associated with the most severe symptoms. It is often detected during childhood.
Your doctor may want to order this test in the following situations:
- When you have bleeding problems, along with normal prothrombin time (PT) and normal or prolonged activated partial thromboplastin time (aPTT).
- To monitor treatment of von Willebrand disease.
You should visit your doctor if you experience any of the following signs and symptoms:
- Bruises of unknown origin
- Nosebleeds
- Heavy menstrual bleeding
- Bleeding gums or rectum
- A skin rash with small red or purple dots
- Blood in the stools or urine
- Wounds that do not stop bleeding on its own, or that take too much time to heal
- Frequent headaches
- Chest pain
- Temporary vision changes
Normal vWF antigen and vWF activity (Ristocetin Cofactor) concentrations can vary depending on the person’s blood type, but they both range from 50% to 150% (50-200 IU/dl).
Interpretation of VWF test results can be difficult; therefore, it should be performed by a doctor who specializes in bleeding disorders. Nevertheless, in general terms, it could be synthesized as follows:
- Normal vWF activity but decreased vWF antigen levels: this is suggestive of type 1 von Willebrand Disease or, more rarely, acquired von Willebrand Disease.
- Decreased vWF activity (Ristocetin Cofactor) with normal vWF antigen levels: this may indicate type 2 von Willebrand Disease. Further testing, such as vWF multimeric analysis, must be performed to determine which subtype is present (2A, 2B, 2M, or 2N).
- Decreased or undetectable vWF activity along with decreased or undetectable vWF antigen levels are highly suggestive of type 3 von Willebrand Disease. Very low factor VIII levels usually accompany this type of VWD.
Increased levels of vWF antigen and vWF activity are not considered diagnostic as they can be elevated in several conditions including infections, trauma, inflammation, stress, pregnancy, and use of oral contraceptives.
1. LabCorp 084715: von Willebrand Factor (vWF) Profile [accessed on Dec 05, 2018]
2. Lab Tests Online: von Willebrand Factor [accessed on Dec 05, 2018]
3. Blood Test: von Willebrand Factor (vWF) Activity - Ristocetin Cofactor (for Parents) [accessed on Dec 05, 2018]
4. Von Willebrand disease - Diagnosis and treatment - Mayo Clinic [accessed on Dec 11, 2018]
5. VWFX - Clinical: von Willebrand Factor Activity, Plasma [accessed on Dec 11, 2018]
6. 086280: von Willebrand Factor (vWF) Antigen | LabCorp [accessed on Dec 11, 2018]
7. Von Willebrand Panel - Health Encyclopedia - University of Rochester Medical Center [accessed on Dec 11, 2018]
8. Von Willebrand Disease: An Overview [accessed on Dec 11, 2018]

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."

Von Willebrand Factor Multimers Test

Von Willebrand Factor Multimers Test

Also called: vWf Multimers

When a wound occurs in any part of the body, several factors (proteins) which are involved in the normal blood clotting process become active to stop the bleeding; one of these factors is the von Willebrand Factor (vWF). Decreased levels of vWF are suggestive of von Willebrand disease (VWD), which is the most common inherited bleeding disorder. This test...

Von Willebrand Factor Multimers Test

Also called: vWf Multimers

When a wound occurs in any part of the body, several factors (proteins) which are involved in the normal blood clotting process become active to stop the bleeding; one of these factors is the von Willebrand Factor (vWF). Decreased levels of vWF are suggestive of von Willebrand disease (VWD), which is the most common inherited bleeding disorder. This test...

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Use the slider below to see how your results affect your health.
Your result is Type 1.
Too little of the vWF is present in your blood. This is the mildest and most common form of the disease.
Related conditions
von Willebrand disease
von Willebrand disease (VWD) is a condition that causes the blood to not clot properly due to deficient and/or defective von Willebrand Factor. This puts the affected person at risk of uncontrolled bleeding.
VWD is the most common inherited bleeding disorder, which means that is usually transmitted from parents to children. Although, it can also occur spontaneously.
This disease has several variations that range from mild to severe:
- Type 1: too little of the vWF is present in your blood. This is the mildest and most common form of the disease.
- Type 2: you have normal vWF levels, but the protein is defective. Bleeding may be more severe with this form of the disease. Type 2 VWD is further divided into several subtypes (2A, 2B, 2M, or 2N).
- Type 3: your vWF is completely missing. This is the rarest form of the disease, and it’s usually associated with the most severe symptoms. It is often detected during childhood.
You should visit your doctor if you experience any of the following signs and symptoms:
- Bruises of unknown origin
- Nosebleeds
- Heavy menstrual bleeding
- Bleeding gums or rectum
- A skin rash with small red or purple dots
- Blood in the stools or urine
- Wounds that do not stop bleeding on its own, or that take too much time to heal
- Frequent headaches
- Chest pain
- Temporary vision changes
1. Von Willebrand Disease: An Overview [accessed on Dec 11, 2018]
2. 500148: von Willebrand Factor (vWF) Multimers | LabCorp [accessed on Dec 11, 2018]
3. https://www.labcorp.com/sites/testmenu/files/500148.pdf [accessed on Dec 11, 2018]
4. VWFM2 - Clinical: von Willebrand Factor Multimer Analysis, Plasma [accessed on Dec 11, 2018]
5. von Willebrand Factor Multimers: Reference Range, Interpretation, Collection and Panels [accessed on Dec 11, 2018]

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."

Treatment

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels.

Image by MarinaVladivostok

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels.

Desmopressin, sold under the trade name DDAVP among others, is a medication used to treat diabetes insipidus, bedwetting, hemophilia A, von Willebrand disease, and high blood urea levels. In hemophilia A and von Willebrand disease, it should only be used for mild to moderate cases. It may be given in the nose, by injection into a vein, by mouth, or under the tongue. - Wikipedia

Image by MarinaVladivostok

What Are the Treatments for Von Willebrand Disease?

The type of treatment prescribed for VWD depends on the type and severity of the disease. For minor bleeds, treatment might not be needed.

The most commonly used types of treatment are:

Desmopressin Acetate Injection

This medicine (DDAVP) is injected into a vein to treat people with milder forms of VWD (mainly Type 1). It works by making the body release more VWF into the blood. It also helps increase the level of factor VIII in the blood.

Desmopressin Acetate Nasal Spray

This high-strength nasal spray (Stimate) is used to treat people with milder forms of VWD (mainly Type 1). It works by making the body release more VWF into the blood.

Factor Replacement Therapy

Recombinant VWF (such as Vonvendi) and medicines rich in VWF and factor VIII (for example, Humate P, Wilate, Alphanate, or Koate DVI) are used to treat people with more severe forms of VWD or people with milder forms of VWD who do not respond well to the nasal spray. These medicines are injected into a vein in the arm to replace the missing factor in the blood.

Antifibrinolytic Drugs

These drugs (for example, Amicar, Lysteda) are either injected or taken orally to help slow or prevent the breakdown of blood clots.

Birth Control Pills

Birth control pills can increase the levels of VWF and factor VIII in the blood and reduce menstrual blood loss. A doctor can prescribe these pills for women who have heavy menstrual bleeding.

Source: Centers for Disease Control and Prevention (CDC)

Additional Materials (2)

Von Willebrand disease

Video by Diane Atwood/YouTube

Management | ASH Clinical Practice Guidelines on Von Willebrand Disease (VWD)

Video by American Society of Hematology/YouTube

3:21

Von Willebrand disease

Diane Atwood/YouTube

4:01

Management | ASH Clinical Practice Guidelines on Von Willebrand Disease (VWD)

American Society of Hematology/YouTube

Pregnancy

Blood conditions and Pregnancy

Image by TheVisualMD

Blood conditions and Pregnancy

Blood conditions and Pregnancy

Image by TheVisualMD

VWD Information for Women

Pregnancy and Childbirth

With proper care, women with von Willebrand disease (VWD) can have a successful pregnancy and deliver a healthy child. A woman who has VWD should be monitored closely throughout her pregnancy by her doctors.

It is important for a woman’s health care providers to be aware that she has VWD so that plans can be made for a safe delivery. If a woman is receiving care at a hemophilia treatment center, those doctors and nurses should be involved and work closely with the doctor who is delivering the woman’s baby. Working together in this way will help the doctor who is delivering the baby take special safety measures to avoid injury. These safety measures include not using forceps or a vacuum extractor to assist in the delivery of the baby, if possible. The same precautions to protect the baby apply if the father has VWD.

After Delivery

Women with VWD are at risk for serious bleeding after delivery. During any pregnancy, the body makes higher amounts of clotting factors to prevent bleeding. However, the high levels of clotting factors during pregnancy drop back to lower levels after delivery. If the woman has low levels of clotting factor, then she can bleed after delivery or surgery (for example, following a Cesarean section). Some women have bleeding from the birth canal that lasts a long time. This is called postpartum hemorrhage and can require treatment to stop the bleeding.

Tips

To reduce the chances of having problems during pregnancy and after delivery, a woman with VWD should:

Talk to her doctor about her bleeding disorder before becoming pregnant.
Think about seeing a doctor who specializes in high-risk pregnancies and a hospital that has a hematologist (a doctor who specializes in bleeding disorders) on staff for prenatal care and delivery.
Talk to her doctor before having any prenatal tests or medical procedures (for example, amniocentesis) to find out whether anything needs to be done to prevent serious blood loss.
Have blood tests done during her third trimester to measure the levels of VWF and factor VIII in her blood to help plan for delivery.
Meet with an anesthesiologist (a doctor who specializes in giving patients medicines for pain relief) to review her options for pain medicine and to discuss taking medicine to lower her risk of bleeding.

To reduce the chances that her baby will have a problem after delivery, a woman with VWD or a woman having a baby with a man who has VWD should:

Talk to her doctor about the chance that her baby will have VWD and any special plans that need to be made for the baby at the hospital where she will deliver.

Source: Centers for Disease Control and Prevention (CDC)

Additional Materials (3)

Women and Bleeding Disorders: Living with von Willebrand Disease

Video by Centers for Disease Control and Prevention (CDC)/YouTube

How will Von Willebrand disease affect my bleeding during and after delivery?

Video by IntermountainMoms/YouTube

Women and Bleeding Disorders - The impact of menstruation

Video by European Haemophilia Consortium/YouTube

7:25

Women and Bleeding Disorders: Living with von Willebrand Disease

Centers for Disease Control and Prevention (CDC)/YouTube

2:34

How will Von Willebrand disease affect my bleeding during and after delivery?

IntermountainMoms/YouTube

5:22

Women and Bleeding Disorders - The impact of menstruation

European Haemophilia Consortium/YouTube

Related HealthJournals

Bleeding Disorders in Women

A bleeding disorder is a health problem that makes it difficult for a person to stop bleeding. Bleeding disorders may affect 1 in 10 women with heavy periods and can cause other health problems if not treated.

Bleeding Disorders

Normally, if you get hurt, your body forms a blood clot to stop the bleeding. For blood to clot, your body needs cells called platelets and proteins known as clotting factors. If you have a bleeding disorder, you either do not have enough platelets or clotting factors, or they don't work the way they should. Read more about bleeding disorders and treatments.

Heavy Menstrual Bleeding

Heavy menstrual bleeding (formerly known as menorrhagia) refers to unusually heavy or long menstrual periods. Learn about the causes, signs, diagnosis and treatments for heavy menstrual bleeding.

Factor V Deficiency

Factor V deficiency is an inherited bleeding disorder that prevents blood clots from forming properly. This disorder is caused by mutations in the F5 gene, which leads to a deficiency of a protein called coagulation factor V.

Factor V Leiden Thrombophilia

Factor V Leiden thrombophilia is an inherited disorder of blood clotting. Factor V Leiden is the name of a specific gene mutation that results in thrombophilia, which is an increased tendency to form abnormal blood clots that can block blood vessels.

Factor XIII Deficiency

Factor XIII deficiency is an extremely rare inherited blood disorder characterized by abnormal blood clotting that may result in abnormal bleeding. In affected individuals, the blood fails to clot appropriately, resulting in poor wound healing. Blood may seep into surrounding soft tissues, resulting in local pain and swelling.

Factor X Deficiency

Factor X deficiency is a rare disorder that affects the blood's ability to clot. The severity of the disorder and the associated signs and symptoms can vary significantly from person to person.

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Von Willebrand Disease

Von Willebrand disease (VWD) is a bleeding disorder that slows the blood clotting process, causing prolonged bleeding after an injury. VWD is the most common bleeding disorder, found in up to 1% of the U.S. population. There are 3 major types of VWD: Type 1, Type 2, and Type 3. Learn more about this bleeding disorder and how it's managed.

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