[Sudomotor dysfunction in Parkinson's disease].

Sudomotor function was evaluated by using the sympathetic skin response (SSR) and the sweat response to intradermal acetylcholine (ACh) injection in 69 patients with Parkinson's diseases (PD). The incidence of SSR abnormality (34.8%) was as high as that of orthostatic hypotension (30.4%) and increased with the severity of the illness. Anticholinergic drug did not influence the incidence of SSR abnormality. Therefore, the SSR is useful in evaluating sudomotor efferent pathway in PD patients. Moreover, in all patients, sweat response to ACh showed a reduced number of excitable sweat glands and a low volume of sweat. In a patient in whom sweat response to ACh was markedly impaired, however, the density of acetylcholinesterase-positive unmyelinated fibers in biopsied sural nerve was in normal range. Therefore, this is considered to indicate functional disturbance of the postganglionic sympathetic fibers in PD patients, without morphological changes.