Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical condition such as alcoholism, a tumor, or a stroke. Other causes may include toxins, chemicals, and viruses. Sometimes the cause is not known.

Degenerative nerve diseases include

• Alzheimer's disease
• Amyotrophic lateral sclerosis
• Friedreich's ataxia
• Huntington's disease
• Lewy body disease
• Parkinson's disease
• Spinal muscular atrophy

Degenerative nerve diseases can be serious or life-threatening. It depends on the type. Most of them have no cure. Treatments may help improve symptoms, relieve pain, and increase mobility.

Rett syndrome is a rare genetic disease that causes developmental and nervous system problems, mostly in girls. It's related to autism spectrum disorder. Babies with Rett syndrome seem to grow and develop normally at first. Between 3 months and 3 years of age, though, they stop developing and even lose some skills. Symptoms include

• Loss of speech
• Loss of hand movements such as grasping
• Compulsive movements such as hand wringing
• Balance problems
• Breathing problems
• Behavior problems
• Learning problems or intellectual disability

Rett syndrome has no cure. You can treat some of the symptoms with medicines, surgery, and physical and speech therapy. Most people with Rett syndrome live into middle age and beyond. They will usually need care throughout their lives.

What is polio?

Polio, or poliomyelitis, is a disease that spreads from person to person. It is caused by the poliovirus. The virus attacks the nervous system. In serious cases, it can cause paralysis (where you can't move parts of the body). The paralysis may be lifelong and can sometimes be life-threatening.

Because of vaccines, polio is rare in the United States. But polio does occur in some parts of the world, and travelers can spread the virus.

How does polio spread?

The poliovirus is very contagious. It spreads through contact with:

• The stool (poop) of person who has the infection
• Droplets from a sneeze or cough of someone who has the infection

This contact can happen if:

• You get contaminated stool or droplets on your hands and then touch your mouth
• A child puts contaminated toys or other objects into their mouth
• You share food or utensils with someone who has the infection

People who have the infection can spread it to others just before and up to several weeks after the symptoms appear. People who don't have symptoms can still spread the virus to others and make them sick.

Who is more likely to develop polio?

Polio mainly affects children under age 5. But people of any age (including adults) who are unvaccinated are at risk of developing polio. People who live in or travel to areas where there is polio are more likely to get polio.

What are the symptoms of polio?

Most people who get infected with poliovirus do not have any symptoms. But one out of four people who get polio will have flu-like symptoms. These symptoms usually last 2 to 5 days, and they include:

• Sore throat
• Fever
• Fatigue
• Nausea
• Headache
• Stomach pain

In rare cases, polio can be very serious. It can lead to:

• Meningitis, an infection of the covering of your spinal cord and/or brain.
• Weakness or paralysis in your arms, legs, or both. This paralysis or weakness can last a lifetime. It is possible for the paralysis to become life-threatening if it affects the muscles that you use to breathe.
• Post-polio syndrome (PPS), which happens later in life.

What is post-polio syndrome (PPS)?

Post-polio syndrome (PPS) is a condition that affects polio survivors many years after they recovered from polio. It usually happens 15-40 years later. It is not contagious.

People who get PPS start having new weakening in muscles that were previously affected by the polio infection. Symptoms may range from mild to serious. The symptoms of PPS include:

• Muscle weakness
• Muscle atrophy (wasting away of muscles)
• Loss of muscle function
• Mental and physical fatigue
• Joint pain
• Curving of the spine (scoliosis)

PPS is rarely life-threatening, but the symptoms can interfere with your daily life.

How is polio diagnosed?

If you think you or someone in your family has symptoms of polio, call your healthcare provider right away or go to an emergency room.

To find out if you or your child has polio, the provider:

• Will do a physical exam.
• Will take a detailed medical history, including your vaccination history and history of any recent travel.
• Will collect samples of body fluids, such as stool, saliva, blood, urine, and spinal fluid. Poliovirus is most likely to be detected in stool specimens.
• May do an MRI to look at pictures of the spinal cord.

What are the treatments for polio and post-polio syndrome (PPS)?

There is no cure or specific treatment for polio. For a mild case, getting rest and drinking plenty of liquids may help with some of the symptoms.

If the polio is more serious, you or your child may need:

• Physical or occupational therapy to help with arm or leg weakness. The earlier therapy is started, the better.
• Pain relievers to help with pain and treat fever. If your child is sick, do not give them aspirin unless their provider tells you to.
• A ventilator to help with breathing if the breathing muscles are weak or paralyzed.

There is no cure for PPS. Treatments may help you manage your symptoms. They include:

• Non-fatiguing exercises (exercises that do not cause pain or fatigue that lasts more than 10 minutes). These exercises may improve muscle strength and reduce tiredness. Your provider can help you figure out which exercises are best for you.
• Mobility aids.
• Ventilation equipment.
• Lifestyle changes, such as eating a healthy diet, getting enough sleep, and not smoking.

Can polio be prevented?

There are two types of vaccine that can prevent polio:

• Inactivated poliovirus vaccine (IPV) given as an injection in the leg or arm, depending on how old you are. Since 2000, this has been the only polio vaccine used in the United States.
• Oral poliovirus vaccine (OPV) is given as drops in the mouth. It is still used throughout much of the world.

Children in the United States get four doses of PV as part of their routine childhood immunizations. Most adults in the United States were vaccinated against polio as children.

There is a one-time IPV booster. It may be given to adults who have completed their polio vaccinations but are at higher risk of contact with poliovirus. You may be at higher risk if you are:

• Traveling to a country where the risk of getting polio is greater
• Working in a laboratory or healthcare setting and handling samples that might contain polioviruses
• A healthcare worker who has contact with patients who could have polio

Another way to help prevent the spread of polio is to wash your hands often with soap and water. Alcohol-based hand sanitizers will not kill poliovirus.

What are peripheral nerves?

Nerves are like wires that carry messages back and forth between your brain and your body. Your peripheral nerves branch off from your brain and spinal cord and connect to all parts of your body, including your muscles and organs. Peripheral nerves carry messages from your brain that control your movement, breathing, heartbeat, digestion, and more. They also carry messages from your body to your brain, so you can feel things, such as pain, heat, and cold.

What are peripheral nerve disorders?

Peripheral nerve disorders happen when one or more peripheral nerves are damaged. Damaged nerves may not carry messages correctly, or they may not work at all. As a result, you may have pain, trouble walking, or a variety of other problems, depending on which nerves are involved.

Peripheral nerve disorders are very common. There are more than 100 different types.

What causes peripheral nerve disorders?

Many things can damage nerves and lead to peripheral nerve disorders:

• Diabetes is the most common cause of peripheral nerve disorders. Most people with diabetes will develop diabetic nerve problems.
• Physical injury (trauma) that stretches, crushes, squeezes, cuts, or puts pressure on one or more nerves. Some examples of peripheral nerve disorders from physical injury include complex regional pain syndrome and brachial plexus injuries.
• Health conditions, including:
  • Certain cancers and their treatment (chemotherapy and radiation therapy).
  • Infections, such as HIV and Lyme disease.
  • Problems with blood or blood vessels.
  • Autoimmune diseases, such as rheumatoid arthritis and lupus.
  • Kidney or liver disease.
• Certain medicines.
• Contact with certain toxic substances, such as lead or mercury.
• Alcohol use disorder (AUD) and smoking.
• Vitamin imbalances, especially a lack of vitamin B12.
• Your genes, including changes in your genes or conditions that you inherit from your parents, such as Charcot-Marie-Tooth disease.

In certain cases, the cause of peripheral nerve disorder is not known.

What are the symptoms of peripheral nerve disorders?

The symptoms of peripheral nerve disorders depend on which nerves are affected, what is causing the damage, and how serious it is:

Symptoms may range from mild to very strong. They may develop quickly over days or slowly over months and years. But they are rarely life-threatening.

How are peripheral nerve disorders diagnosed?

To find out if you have a peripheral nerve disorder, your provider will:

• Ask about your medical history
• Ask about your family health history
• Do a physical exam
• Order tests, which may include:
  • Blood tests
  • Genetic tests
  • Nerve tests that measure:
    • Electrical activity in your nerves and muscles
    • How well your autonomic nerves are working
  • A biopsy of nerve or skin tissue
  • CT or MRI scan to see what may be pressing on your nerves

What are the treatments for peripheral nerve disorders?

It's important to treat any conditions that are causing nerve damage. In certain cases, that will allow your nerves to heal over time.

Treatment for symptoms depends on the type of peripheral nerve disorder you have, where it is, and how severe. Treatment options include:

• Braces or splints
• Over-the-counter patches and skin creams
• Prescription medicines
• Non-drug pain management, such as electrical stimulation or relaxation therapy
• Surgery to relieve pressure on a nerve

Can peripheral nerve disorders be prevented?

You can help prevent peripheral nerve disorders by:

• Managing health conditions that may cause nerve damage, especially diabetes
• Preventing falls and accidents
• Avoiding toxic substances
• Being careful to avoid repeated motions and body positions that press on your nerves
• Eating a balanced diet, exercising, limiting alcohol, and not smoking

Parkinson's disease (PD) is a type of movement disorder. It happens when nerve cells in the brain don't produce enough of a brain chemical called dopamine. Sometimes it is genetic, but most cases do not seem to run in families. Exposure to chemicals in the environment might play a role.

Symptoms begin gradually, often on one side of the body. Later they affect both sides. They include

• Trembling of hands, arms, legs, jaw and face
• Stiffness of the arms, legs and trunk
• Slowness of movement
• Poor balance and coordination

As symptoms get worse, people with the disease may have trouble walking, talking, or doing simple tasks. They may also have problems such as depression, sleep problems, or trouble chewing, swallowing, or speaking.

There is no lab test for PD, so it can be difficult to diagnose. Doctors use a medical history and a neurological examination to diagnose it.

PD usually begins around age 60, but it can start earlier. It is more common in men than in women. There is no cure for PD. A variety of medicines sometimes help symptoms dramatically. Surgery and deep brain stimulation (DBS) can help severe cases. With DBS, electrodes are surgically implanted in the brain. They send electrical pulses to stimulate the parts of the brain that control movement.

Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord. It damages the myelin sheath, the material that surrounds and protects your nerve cells. This damage slows down or blocks messages between your brain and your body, leading to the symptoms of MS. They can include

• Visual disturbances
• Muscle weakness
• Trouble with coordination and balance
• Sensations such as numbness, prickling, or "pins and needles"
• Thinking and memory problems

No one knows what causes MS. It may be an autoimmune disease, which happens when your immune system attacks healthy cells in your body by mistake. Multiple sclerosis affects women more than men. It often begins between the ages of 20 and 40. Usually, the disease is mild, but some people lose the ability to write, speak, or walk.

There is no single test for MS. Doctors use a medical history, physical exam, neurological exam, MRI, and other tests to diagnose it. There is no cure for MS, but medicines may slow it down and help control symptoms. Physical and occupational therapy may also help.

A genetic brain disorder is caused by a variation or a mutation in a gene. A variation is a different form of a gene. A mutation is a change in a gene. Genetic brain disorders affect the development and function of the brain.

Some genetic brain disorders are due to random gene mutations or mutations caused by environmental exposure, such as cigarette smoke. Other disorders are inherited, which means that a mutated gene or group of genes is passed down through a family. They can also be due to a combination of both genetic changes and other outside factors.

Some examples of genetic brain disorders include

• Leukodystrophies
• Phenylketonuria
• Tay-Sachs disease
• Wilson disease

Many people with genetic brain disorders fail to produce enough of certain proteins that influence brain development and function. These brain disorders can cause serious problems that affect the nervous system. Some have treatments to control symptoms. Some are life-threatening.

Friedreich's ataxia is an inherited disease that damages your nervous system. The damage affects your spinal cord and the nerves that control muscle movement in your arms and legs. Symptoms usually begin between the ages of 5 and 15. The main symptom is ataxia, which means trouble coordinating movements. Specific symptoms include

• Difficulty walking
• Muscle weakness
• Speech problems
• Involuntary eye movements
• Scoliosis (curving of the spine to one side)
• Heart palpitations, from the heart disease which can happen along with Friedreich's ataxia

People with Friedreich's ataxia usually need a wheelchair 15 to 20 years after symptoms first appear. In severe cases, people become incapacitated. There is no cure. You can treat symptoms with medicines, braces, surgery, and physical therapy.

Creutzfeldt-Jakob disease (CJD) is a rare, degenerative brain disorder. Symptoms usually start around age 60. Memory problems, behavior changes, vision problems, and poor muscle coordination progress quickly to dementia, coma, and death. Most patients die within a year.

The three main categories of CJD are

• Sporadic CJD, which occurs for no known reason
• Hereditary CJD, which runs in families
• Acquired CJD, which occurs from contact with infected tissue, usually during a medical procedure

Cattle can get a disease related to CJD called bovine spongiform encephalopathy (BSE) or "mad cow disease." There is concern that people can get a variant of CJD from eating beef from an infected animal, but there is no direct proof to support this.

When you play the piano or hit a tennis ball you are activating the cerebellum. The cerebellum is the area of the brain that controls coordination and balance. Problems with the cerebellum include

• Cancer
• Genetic disorders
• Ataxias - failure of muscle control in the arms and legs that result in movement disorders
• Degeneration - disorders caused by brain cells decreasing in size or wasting away

Treatment of cerebellar disorders depends on the cause. In some cases, there is no cure but treatment may help with symptoms.

Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body. Your nerves take in information from your senses and send it to the brain to be processed. Your brain and nerves also communicate to help you move and to control your body's functions.

When the brain is healthy, it works quickly and automatically. But when you have a brain disease, it may affect how well you can function and do your daily activities. Some common brain diseases include:

• Brain tumors, which can press on nerves and affect brain function.
• Degenerative nerve diseases, which can affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Types include Alzheimer's disease and Parkinson's disease.
• Encephalitis (inflammation in the brain), which can lead to problems such as vision loss, weakness, and paralysis.
• Genetic brain disorders, which are caused by changes in genes (also called variants or mutations). These disorders can affect the development and function of the brain.
• Strokes, which can cause a loss of brain cells and can affect your ability to think clearly.
• Traumatic brain injuries (TBIs), which can affect brain function. They may range from mild to severe. The effects of a TBI may be temporary or permanent.

The symptoms of brain diseases vary widely, depending on the specific problem. In some cases, damage is permanent. In other cases, treatments such as surgery, medicines, or therapies such as physical, occupational, and speech therapies, may cure the disease or improve the symptoms.

Amyotrophic lateral sclerosis (ALS) is a nervous system disease that attacks nerve cells called neurons in your brain and spinal cord. These neurons transmit messages from your brain and spinal cord to your voluntary muscles - the ones you can control, like in your arms and legs. At first, this causes mild muscle problems. Some people notice

• Trouble walking or running
• Trouble writing
• Speech problems

Eventually, you lose your strength and cannot move. When muscles in your chest fail, you cannot breathe. A breathing machine can help, but most people with ALS die from respiratory failure.

The disease usually strikes between age 40 and 60. More men than women get it. No one knows what causes ALS. It can run in families, but usually it strikes at random. There is no cure. Medicines can relieve symptoms and, sometimes, prolong survival.

Alzheimer's disease (AD) is the most common form of dementia among older people. Dementia is a brain disorder that seriously affects a person's ability to carry out daily activities.

AD begins slowly. It first involves the parts of the brain that control thought, memory and language. People with AD may have trouble remembering things that happened recently or names of people they know. A related problem, mild cognitive impairment (MCI), causes more memory problems than normal for people of the same age. Many, but not all, people with MCI will develop AD.

In AD, over time, symptoms get worse. People may not recognize family members. They may have trouble speaking, reading or writing. They may forget how to brush their teeth or comb their hair. Later on, they may become anxious or aggressive, or wander away from home. Eventually, they need total care. This can cause great stress for family members who must care for them.

AD usually begins after age 60. The risk goes up as you get older. Your risk is also higher if a family member has had the disease.

No treatment can stop the disease. However, some drugs may help keep symptoms from getting worse for a limited time.

Neurodegeneration with brain iron accumulation (NBIA) is a rare, inherited, neurological movement disorder characterized by an abnormal accumulation of iron in the brain and progressive degeneration of the nervous system. Several genes have been found that cause NBIA.

Symptoms, which vary greatly and usually develop during childhood, can include:

• Dystonia (slow writhing, distorting muscle contractions of the limbs, face, or trunk)
• Dysarthria (slurred or slow speech)
• Choreoathetosis (involuntary, purposeless jerky muscle movements)
• Muscle rigidity (uncontrolled tightness of the muscles)
• Spasticity (sudden, involuntary muscle spasms)

• Ataxia (inability to coordinate movements)
• Confusion
• Seizures
• Stupor
• Dementia
• Visual changes

Cognitive decline occurs in some forms of NBIA, however, the majority of individuals with NBIA do not have cognitive impairment.

NBIA is a progressive condition. Most individuals experience periods of rapid decline lasting weeks to months, with relatively stable periods in between. The rate of progression correlates with the age at onset. For those with early onset, dystonia and spasticity can eventually limit the ability to walk.

There is no cure for NBIA, nor is there a standard course of treatment. Treatment is symptomatic and supportive, and may include physical or occupational therapy, exercise physiology, and/or speech pathology.

Ataxia often occurs when parts of the nervous system that control movement are damaged. People with ataxia experience a failure of muscle control in their arms and legs, resulting in a lack of balance and coordination or a disturbance of gait. While the term ataxia is primarily used to describe this set of symptoms, it is sometimes also used to refer to a family of disorders. It is not, however, a specific diagnosis.

Most disorders that result in ataxia cause cells in the part of the brain called the cerebellum to degenerate, or atrophy. Sometimes the spine is also affected. The phrases cerebellar degeneration and spinocerebellar degeneration are used to describe changes that have taken place in a person's nervous system (neither term constitutes a specific diagnosis). Cerebellar and spinocerebellar degeneration have many different causes.

Many ataxias are hereditary and are classified by chromosomal location and pattern of inheritance:

• Autosomal dominant, in which the affected person inherits a normal gene from one parent and a faulty gene from the other parent
• Autosomal recessive, in which both parents pass on a copy of the faulty gene

Among the more common inherited ataxias are Friedreich's ataxia and Machado-Joseph disease. Sporadic ataxias can also occur in families with no prior history.

Ataxia also can be acquired. Conditions that can cause acquired ataxia include stroke, multiple sclerosis, tumors, alcoholism, peripheral neuropathy, metabolic disorders, and vitamin deficiencies.

There is no cure for the hereditary ataxias. If the ataxia is caused by another condition, that underlying condition is treated first. A variety of drugs may be used to either effectively prevent symptoms or reduce the frequency with which they occur. Physical therapy can strengthen muscles, while special devices or appliances can assist in walking and other activities of daily life. The prognosis for individuals with ataxia and cerebellar/spinocerebellar degeneration varies depending on its underlying cause.

What is striatonigral degeneration?

Striatonigral degeneration is a neurological disorder caused by a disruption in the connection between two areas of the brain-the striatum and the substantia nigra. These two areas work together to enable balance and movement. Striatonigral degeneration is a type of multiple system atrophy (MSA). Symptoms of the disorder resemble some of those seen in Parkinson's disease, including rigidity, instability, impaired speech, and slow movements.

Is there any treatment?

There is no cure for striatonigral degeneration, and treatments for the disorder have variable success. Treatments used for Parkinson's disease are recommended. However, unlike Parkinson's disease, striatonigral degeneration is not responsive to levodopa. Dopamine and anticholinergics provide some benefit. Generally, treatment is reevaluated as the disorder progresses.

What is the prognosis?

Striatonigral degeneration progresses slowly. Some patients have normal life expectancy.

Huntington's disease (HD) is an inherited disease that causes certain nerve cells in the brain to waste away. People are born with the defective gene, but symptoms usually don't appear until middle age. Early symptoms of HD may include uncontrolled movements, clumsiness, and balance problems. Later, HD can take away the ability to walk, talk, and swallow. Some people stop recognizing family members. Others are aware of their environment and are able to express emotions.

If one of your parents has Huntington's disease, you have a 50 percent chance of getting it. A blood test can tell you if have the HD gene and will develop the disease. Genetic counseling can help you weigh the risks and benefits of taking the test.

There is no cure. Medicines can help manage some of the symptoms, but cannot slow down or stop the disease.