Familial Dysautonomia

What is familial dysautonomia?

Familial dysautonomia (FD) is a condition that causes problems with your nervous system. You have this condition from birth.

Familial dysautonomia affects your body’s involuntary actions, such as:

• Breathing.
• Digesting.
• Forming tears.
• Regulating your blood pressure and body temperature.
• Salivating.

It also affects your sensory nervous system. This includes:

• Ability to taste.
• Sensitivity to pain and temperature.

You inherit FD from a gene change (mutation) passed down from your parents. Familial dysautonomia is also called:

• Riley-Day syndrome.
• Type III hereditary sensory and autonomic neuropathy (HSAN type III).

Familial dysautonomia can increase the risk of developmental delay. People with this condition also have shorter life expectancies.

Who might get familial dysautonomia?

You must inherit a defective gene from each of your parents to develop familial dysautonomia. FD mainly affects people of Ashkenazi Jewish heritage.

How common is familial dysautonomia?

Familial dysautonomia is a rare condition. An estimated 1 in 10,000 Ashkenazi Jews in the United States and 1 in 3,700 Ashkenazi Jews in Israel have this condition at birth.

What causes familial dysautonomia?

Genetic changes (mutations) cause familial dysautonomia. Both of your parents must carry a mutation in a gene called ELP1. The ELP1 gene makes a protein that helps your nervous system develop. If this gene has a mutation, problems occur with parts of your nervous system.

What are the symptoms of familial dysautonomia?

Symptoms of FD begin in infancy. Early symptoms may include:

• Difficulty feeding.
• Difficulty swallowing (dysphagia).
• Inability to maintain body temperature.
• Lack of tears when crying.
• Poor growth.
• Poor muscle tone (hypotonia).

As a child ages, they may hold their breath for extended periods of time. This breath-holding behavior usually ends by 6 years of age.

As the disease progresses, symptoms may include:

• Abnormal heart rhythms (arrhythmia).
• Abnormal sense of taste.
• Abnormal spine curving (scoliosis).
• Balance problems and gait disorders.
• Bedwetting.
• Chronic acid reflux (GERD).
• Developmental delays, such as delayed speech and trouble walking.
• Excess saliva.
• Eye problems, including dry eyes and crossed eyes (strabismus).
• Inability to feel pain and temperature changes.
• Low vision and vision loss.
• Lung infections.
• Poor bone quality (osteoporosis) and increased risk of bone fractures.
• Poor control of breathing, especially during sleep.
• Seizures (epilepsy).
• Vomiting.

Many people with familial dysautonomia have problems regulating blood pressure. This can lead to low blood pressure (orthostatic hypotension) when standing, which can cause dizziness or fainting. High blood pressure (hypertension) can also lead to kidney disease.

About 40% of people with FD have periods of time when symptoms worsen (autonomic crises). During these times, you may experience:

• Fever.
• Heart palpitations.
• High blood pressure.
• Reddish skin.
• Sweating.
• Vomiting.

How is familial dysautonomia diagnosed?

Your healthcare provider will first ask about your symptoms. They will also do a physical exam.

Your provider will look for an absence of tears when you cry. For children younger than 6 months, they may use the Schirmer test:

• They place the end of filter paper in the far corner of your child’s lower eyelid.
• After five minutes, less than 10 ml of wetness means your child may have familial dysautonomia.

Your provider will also look for:

• Decreased tendon reflexes: If you have FD, you won’t react when a provider taps your muscles.
• Reaction to a histamine injection: If you have FD, the injection won’t cause redness and swelling.
• Reaction to eye drops (methacholine): After about 20 minutes, you will have smaller pupils if you have FD.
• Smooth-looking tongue: If you have FD, you lack structures that house taste buds in the center of the back of your tongue (fungiform papillae).

If your provider suspects FD, they may suggest genetic testing. This involves a blood test to check for the gene change (mutation) that causes familial dysautonomia.

How is familial dysautonomia treated?

FD treatment focuses on reducing your symptoms. Treatments may include:

• Antibiotics or chest physiotherapy to help with lung infections.
• Compression socks or a permanent pacemaker to address orthostatic hypotension.
• CPAP or bilevel positive airway pressure (often known under the trade name BiPAP®) to help with breathing during sleep.
• Eye drops to protect your corneas.
• IV fluids to rehydrate after vomiting.
• Medications to help with GERD, kidney disease, saliva production, seizures or vomiting.
• Occupational therapy to assist with day-to-day activities.
• Physical therapy to improve balance.
• Surgery to help with spine problems.
• Tube feeding (enteral nutrition) for increased nutrition.

Researchers continue to study new treatments in clinical trials. These treatments could help treat the disease itself and not only the symptoms.

How can I reduce my risk of familial dysautonomia?

You can’t reduce your risk of FD. But you can look for the signs so you can get prompt monitoring and treatment if needed.

If you have Ashkenazi Jewish heritage and are considering pregnancy, you may want to have genetic counseling. Your provider can also perform genetic testing before or during pregnancy to see if you carry the ELP1 gene.

What is the outlook if I have familial dysautonomia?

There’s no cure for familial dysautonomia. People with FD have reduced life expectancies. About half of people with this condition live into their 30s. Others may live into their 70s.

Symptoms can become worse over time. For instance, about 49% of people with FD need assistance with walking by age 50. You may also have frequent bouts of pneumonia.

How do I take care of myself with familial dysautonomia?

You can help to reduce complications if you:

• Avoid hot or humid weather.
• Limit stressful situations.
• Refrain from long car rides.
• Try not to have a full bladder.

You should also receive regular monitoring from your healthcare provider. They should check your:

• Blood pressure.
• Eyes.
• Kidney function.
• Respiratory function.
• Spine.

A note from Cleveland Clinic

Familial dysautonomia (FD) is a rare genetic condition that affects your nervous system. FD can impact involuntary actions such as breathing, digestion, forming tears, regulating your blood pressure and body temperature and salivating. FD can also affect your ability to taste and sensitivity to pain and temperature. Though there’s no cure for FD, treatments such as medications, therapy and surgery focus on managing your symptoms. People with familial dysautonomia have reduced life expectancies but can lead full lives with proper treatment.