Congenital sensory neuropathies. Diagnostic distinction from familial dysautonomia.

Among congenital sensory neuropathies there are several variants that share features of diminished pain sensitivity and/or autonomic dysfunction with familial dysautonomia but can be shown to be distinct from this entity by clinical and pathologic criteria. Recognition of the unique nature of each disease type is an essential prerequisite for genetic and causative studies. We reviewed the diagnostic tests that can be used in the clinical evaluation of sensory and autonomic function. Based on this process of evaluation, we studied 13 patients who were initially considered to have familial dysautonomia but who were later shown to have five distinct syndromes that were confirmed by neuropathologic studies.