Familial Dysautonomia

What is Familial Dysautonomia?

Familial dysautonomia is an inherited condition that causes nerve cells to deteriorate. It affects the autonomic nervous system, which controls involuntary actions such as breathing, tear production, blood pressure, and body temperature. It also affects the sensory nervous system, which controls senses such as the abilities to perceive taste, pressure, pain, and temperature.

Early symptoms in infants include feeding problems, poor growth, lack of tears, poor muscle tone, frequent lung infections, and marked fluctuations in body temperature. Until about age 6, children with the condition may also hold their breath for long periods of time, which may cause fainting or make their lips or skin appear blue. They may learn to walk and talk later than average.

Starting around age 5 or 6, children with the condition may develop symptoms including bed-wetting, vomiting, reduced sensitivity to temperatures and pain, decreased ability to taste, poor balance, abnormal curvature of the spine, easily fractured bones, and kidney and heart problems. They commonly experience a sharp drop in blood pressure when they stand up, which can cause blurred vision, dizziness, or fainting. They may also have episodes of high blood pressure when nervous or excited.

By adulthood, people with familial dysautonomia may have balance problems that prevent them from walking unaided. Other common complications include sleep apnea, lung damage due to repeated infections, poor vision as optic nerves atrophy, and kidney disease. Intellect is not usually impaired.

How Common is Familial Dysautonomia?

Familial dysautonomia is found almost exclusively in people of Ashkenazi Jewish descent, where it affects approximately 1 in 3,700 people. Roughly 1 in 31 Ashkenazi Jews is a carrier of the disease. It is extremely rare in the general population.

How is Familial Dysautonomia Treated?

There is no cure for the cause of familial dysautonomia. Treatment focuses on relieving its symptoms.

Infants with the condition may need to be fed thickened formula to ensure adequate nutrition and prevent them from inhaling their food. Vomiting crises are treated with IV fluids and anti-nausea medication. Recurrent pneumonia caused by inhaling food or vomit requires daily chest physiotherapy. Older children who experience low blood pressure may require elastic stockings and leg exercises to improve muscle tone and prevent blood from pooling in leg veins. Corneal injuries caused by low tear production may be treated with regular eye drops, soft contact lenses, or in rare cases, surgery. Spinal fusion surgery may be necessary to correct scoliosis. Kidney disease may require dialysis. Sleep apnea is generally treated with a machine to support breathing. Many adults require walkers or wheelchairs.

What is the prognosis for a person with Familial Dysautonomia

The average lifespan of a person with familial dysautonomia is significantly shortened. Only 60% of people with the disease survive to age 20.

Familial Dysautonomia Resources
Other Names for Familial Dysautonomia
  • HSN-III
  • HSAN3
  • Riley-Day Syndrome
  • Hereditary Sensory and Autonomic Neuropathy, Type III
  • HSAN III
  • Familial Dysautonomia

 

Take action now to assess your risk for familial dysautonomia and your risk for passing it to your children. To get started with a JScreen genetic test, click here.

Source: Counsyl.