What is familial dysautonomia?
Familial dysautonomia (Riley–Day syndrome, hereditary sensory and autonomic neuropathy type III) is an autosomal recessive disorder affecting primarily people of Ashkenazi Jewish descent.
It affects the development and survival of sensory, sympathetic, and some parasympathetic neurons.
The genetic abnormality responsible for the disease has been identified as the splicing mutation in the IKBKAP (IKB kinase-associated protein) gene on the distal long arm of chromosome 9.
The cardinal clinical features include alacrima (absence of tears), absent fungiform papillae of the tongue, depressed patellar reflexes, and absent skin response to scratch and histamine injection.
Autonomic features result primarily from sympathetic system dysfunction and include transient and emotionally induced erythematous skin blotching, orthostatic hypotension, hyperhidrosis or erratic sweating, and esophageal and GI transit dysfunction.
Dysautonomic crisis is a constellation of symptoms including vomiting, tachycardia, excessive sweating, blotching of the skin, piloerection, ileus, and dilation of the pupils that may occur in response to physiologic or psychologic stress.
