Autonomic involvement in inherited neuropathies.

The inherited peripheral neuropathies constitute a large group of disorders, in some of which the causative metabolic defect has been identified whereas in the majority it is still unknown. Amongst the former, autonomic involvement is an important component in porphyric neuropathy, in the familial amyloid polyneuropathies, in Fabry's disease and in dopamine beta-hydroxylase deficiency. The latter group includes the hereditary sensory and autonomic neuropathies in some of which, such as the Riley-Day syndrome, autonomic disturbances are prominent, whereas in others they constitute only a minor component of the symptomatology. Autonomic dysfunction is an important component of the neurological manifestations in multiple endocrine neoplasia type IIB.