Autonomic dysfunction in peripheral nerve disease.

Autonomic dysfunction is a common complication of peripheral neuropathies. Frequently, it is of little clinical importance, but in some conditions there may be profound disturbance of autonomic function, including orthostatic hypotension, impairment of heart rate and bladder control, and impotence. Some autonomic neuropathies are of acute onset, but most are chronic and of gradual onset. Diseases that primarily affect small fibers in peripheral nerves or cause acute demyelination of small myelinated fibers are those most likely to cause autonomic dysfunction. Conditions that cause severe autonomic dysfunction include acute dysautonomia, familial and primary amyloidosis, Guillain-Barré syndrome, diabetes, porphyria, Chagas' disease, and some hereditary sensory and autonomic neuropathies. Management consists of treating the underlying cause and symptomatic therapy.