Autonomic Disorders Consortium

Information for Patients and Families

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Familial Dysautonomia (FD)

What is Familial Dysautonomia (FD)?

Familial Dysautonomia (FD) is a genetic disease primarily causing dysfunction of the autonomic and sensory nervous systems.

Symptoms displayed by a baby with FD include:

  • Hypotonia (Poor muscle tone)
  • Weak or absent suck
  • Respiratory congestion due to misdirected swallowing
  • Blotching of skin
  • Difficulty in maintaining body temperature

Symptoms in an older child with FD include:

  • Delay in developmental milestones such as walking and speech
  • Poor balance and unsteady gait
  • Scoliosis (spinal curvature)
  • Orthostatic hypotension (extreme drop in blood pressure with change in posture)
  • Breath holding in early years to the point of fainting
  • Episodic vomiting
  • Excessive drooling and sweating
  • A smooth tongue and decrease in sense of taste
  • Difficulty in maintaining body temperature
  • Poor weight gain and growth
  • Frequent lung infections
  • Decreased reaction to pain or no reaction at all
  • Cold, puffy hands and feet
  • Extremes in blood pressure
  • Corneal abrasions and dry eyes
  • Gastric dysmotility (abnormal movement through the stomach)
  • Dysautonomic "crisis" (severe reactions to physical and emotional stress)

Who gets FD?

FD occurs primarily in persons of Ashkenazi (central or eastern European) Jewish descent.

What causes FD?

Familial Dysautonomia is caused by mutations in the IKBKAP gene.
The IKBKAP gene provides instructions for making a protein called IKK complex-associated protein (IKAP). This protein is found in a variety of cells throughout the body, including brain cells.

Nearly all individuals with familial dysautonomia have two copies of the same IKBKAP mutation in each cell.

More information on the IKBKAP gene can be found at Genetics Home Reference

How is FD diagnosed?

To diagnose FD, physicians use health and family history in addition to physical examination. A definitive diagnosis can be made with a blood test. Over 99% of affected individuals will have two copies of the most common gene mutation.

What is the treatment for FD?

Treatment of FD is individualized, since FD symptoms may vary greatly among patients. Treatment often involves managing the most problematic symptoms, such as: