Riley-Day syndrome

Alternative Names

Familial dysautonomia; Hereditary sensory and autonomic neuropathy – type III (HSAN III)

Definition of Riley-Day syndrome

Riley-Day syndrome is an inherited disorder that affects the development and function of nerves throughout the body.

Causes, incidence, and risk factors

Riley-Day syndrome is passed down through families (inherited). A person must inherit a copy of the defective gene from each parent to develop the condition.

Signs and tests

The health care provider will perform a physical exam. The patient may have:


Treatment may include:

Expectations (prognosis)

With advances in diagnosis and treatment, survival continues to improve. Currently, a newborn with Riley-Day has a 50% chance of reaching age 30.


Diana Chambers, MS, EdD, Certified Genetics Counselor (ABMG), Charter Member of the ABGC, University of Tennessee, Memphis, TN. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 10/15/2008

Chromosomes and DNA

ADAM Medical Encyclopedia

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