Understanding Familial Dysautonomia: What You Need to Know About This Rare Nervous System Condition

Have you ever thought about how your body does many things without you even trying? Think about breathing, digesting food, keeping your body at the right temperature, making spit, and crying when you feel sad. All these automatic actions happen because of your nervous system. But what happens if something goes wrong with this system?

Today, we will talk about a rare and serious health condition you are born with. It is called familial dysautonomia (FD). This condition changes how your nerves work and affects your daily life in many ways.

What Is Familial Dysautonomia?

Simply put, familial dysautonomia is a condition you are born with that affects your nervous system. It mainly damages the parts of your body that handle automatic processes. These include:

• Breathing air in and out.
• Digesting food in your stomach.
• Making tears when you cry.
• Controlling your blood pressure and body heat.
• Making spit in your mouth.

Besides these automatic tasks, this condition also affects your sensory nervous system. This changes how you feel:

• The taste of your food.
• Pain and temperature on your skin.

This condition happens because of a gene mutation passed down from your parents. Familial dysautonomia also goes by other medical names:

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

Sadly, this condition can cause developmental delays in children. It may also mean that a person has a shorter life span than average.

Who Is Most Likely to Get This Condition?

To develop familial dysautonomia, a child must receive a faulty gene from both parents. This is a very rare condition. It is seen most often in people of Ashkenazi Jewish ancestry.

Reports show that about 1 in every 10,000 people in the Ashkenazi Jewish population in the United States has it. In Israel, about 1 in every 3,700 people is born with this condition. This means it is not a common disease that affects everyone.

What Causes This Condition?

The root cause of this condition is a gene mutation. Both of your parents must carry a change in the ELP1 gene. This specific gene builds proteins that help your nervous system grow and stay healthy.

If this gene has a flaw, parts of your nervous system will not work right. Think of it like building a house. If you miss one vital piece of material, the whole structure has problems.

What Are the Signs and Symptoms of Familial Dysautonomia?

Symptoms of this condition start right from when you are a baby. Early signs that doctors look for include:

• Trouble drinking milk: Little babies struggle to suck and feed properly.
• Trouble swallowing: Food and drink are hard to swallow, and you might choke.
• Trouble keeping body temperature stable: Your body heat can go up and down without warning.
• No tears when crying: This is a very unique sign. The baby cries, but no tears come out of the eyes.
• Poor growth: The baby does not gain weight or grow tall like other children of the same age.
• Weak muscles: The body feels floppy and lacks normal muscle strength.

As the child grows older, they might hold their breath for short periods. This looks like they are stopping their breath on purpose. Usually, this breath-holding habit stops by the time the child turns six years old.

As the disease progresses over time, more symptoms appear:

• Irregular heartbeat: Your heart beats too fast or skips beats.
• Taste problems: Food does not taste normal or lacks flavor.
• Curved spine (scoliosis): The back bones bend to one side.
• Balance and walking issues: Walking is hard, and you feel like you might fall over.
• Bedwetting: Wetting the bed while sleeping at night.
• Long-term acid reflux (GERD): Frequent heartburn and food coming up into your throat.
• Slow development: Learning to talk or walk takes much longer.
• Drooling: Too much spit falling from the mouth.
• Eye problems: Dry eyes or crossed eyes (strabismus).
• Loss of pain and temperature sense: Hot, cold, or cuts do not hurt like they should.
• Vision loss: Your eyesight gets weak or fades away.
• Lung infections: Mucus builds up in the lungs, causing frequent infections.
• Weak bones (osteoporosis): Bones break much easier.
• Breathing trouble during sleep: Problems controlling breath while sleeping.
• Seizures: Epilepsy or sudden shaking spells.
• Vomiting spells: Sudden throws and upset stomach.

Many people with this condition have blood pressure problems. When you stand up, your blood pressure drops (orthostatic hypotension), making you feel dizzy or faint. High blood pressure can also lead to kidney disease.

About 40% of people with this condition experience autonomic crises. These are times when symptoms get very bad all at once. During a crisis, you might notice:

• Fever.
• Racing heartbeat.
• High blood pressure.
• Red skin.
• Heavy sweating.
• Vomiting.

Think about how hard it is for a young child to go through these constant problems. Parents find it very hard to watch, too. But with proper medical care and advice, you can manage these challenges.

How Do Doctors Diagnose Familial Dysautonomia?

Your doctor will start by asking about your symptoms and doing a physical exam.

A key test checks if you make tears when you cry. For babies under six months old, doctors use the Schirmer test:

• The doctor places a tiny piece of filter paper inside the lower eyelid.
• After five minutes, the doctor measures the wetness on the paper. If it is less than 10 millimeters, the doctor may suspect familial dysautonomia.

The doctor will also check for these signs:

• Low tendon reflexes: When a doctor taps your knee or arm, your muscles do not react normally.
• Histamine skin test: When a person with this condition gets this injection, their skin does not turn red and swell up like it would for a healthy person.
• Eye drop test (methacholine): After putting special drops in the eyes, the pupil shrinks if you have this condition.
• Smooth tongue look: The tiny bumps on your tongue that help you taste (fungiform papillae) are missing, making your tongue look very smooth.

If the doctor spots these signs, they will suggest a genetic test. This test takes a blood sample to look for the gene flaw that causes familial dysautonomia.

What Are the Treatments for Familial Dysautonomia?

Treatment for this condition focuses on managing and reducing symptoms. Doctors use several different methods to help patients feel better:

• For lung infections: Antibiotics or chest physical therapy to clear mucus.
• For low blood pressure when standing: Special compression socks for your legs or a permanent pacemaker for your heart.
• For breathing trouble during sleep: Machines like CPAP or BiPAP® to keep airways open.
• To protect your eyes: Eye drops to keep them moist.
• For dehydration from vomiting: Fluids given through an IV in your arm.
• For GERD, kidney issues, spit control, seizures, or vomiting: Various prescription medicines.
• To make daily tasks easier: Occupational therapy.
• To improve balance: Physical therapy.
• For spine problems: Surgery to fix the back bones.
• For better nutrition: Feeding tubes (enteral nutrition) if swallowing is too hard.

Researchers are also running clinical trials to test new treatments. These studies give hope that future medicines might do more than just manage symptoms—they might help cure the condition.

Can You Lower the Risk of Familial Dysautonomia?

You cannot lower the risk of getting this condition after birth because it is genetic. However, knowing the signs and getting early medical care is the most important step.

If you come from an Ashkenazi Jewish background and plan to have children, genetic counseling is a very smart choice. Your doctor can also test you before or during pregnancy to see if you carry the ELP1 gene.

What Is the Long-Term Outlook for Someone With Familial Dysautonomia?

There is no complete cure yet for familial dysautonomia. People with this condition often have a shorter life span than average. About half of these people live into their 30s, while some live into their 70s.

Hearing this might make you feel scared or sad. But remember that with proper medical care and good support, you can help these people live a happy and fulfilling life.

Symptoms can get worse over time. For example, about 49% of people with this condition need help walking by the time they turn 50. They are also more likely to catch pneumonia and other lung infections.

How Can Someone With Familial Dysautonomia Take Care of Themselves?

You can help lower your risk of health problems by following these tips:

• Stay away from very hot or humid weather.
• Try to keep stress levels low.
• Avoid taking very long trips if possible.
• Do not wait until your bladder is completely full before using the bathroom.

You should also visit your doctor regularly to check:

• Your blood pressure.
• Your eyes and vision.
• Your kidney function.
• Your breathing health.
• Your spine health.

Medical Comparison: Familial Dysautonomia vs. Healthy Nervous System.