We examined autonomic functions in 14 patients with peripheral neuropathy caused by necrotizing vasculitis. These patients consisted of three allergic granulomatous angitis (Churg-Strauss syndrome, AGA), two systemic lupus erythematosus (SLE), two progressive systemic sclerosis (PSS), one mixed connective tissue disease (MCTD), one polyarteritis nodosa (PN) and five nonsystemic vasculitis. All of them were proven to have a vasculitis by sural nerve, muscle or skin biopsy. Sixteen age- and sex-matched healthy volunteers were also examined. Local sweating induced by intradermal injection of pilocarpine and nicotine (a concentration of 10(-4) g/dl, 0.1 ml) was measured with ventilated capsular method on the forearm and lower lateral leg at 23 degrees C of room temperature and 40% of relative humidity. Other autonomic functions including skin temperature at rest and after cold loading (15 degrees C, 6 minutes), variation in the R-R interval of heart beat (CV%), orthostatic hypotension and bladder dysfunction were also monitored. A decrease in sweat rate and recovery rate of skin temperature after cold-loading was seen more frequently in patients with necrotizing vasculitis than normal volunteers. Abnormality in the local sweat response against nicotine and pilocarpine was more frequently present in the involved area of somato-sensory and motor nerves as compared with those in the non-involved area. An occurrence of decrease in recovery rate of skin temperature after cold-loading also well correlated to the region of somato-sensory- and motor involvement. So far other autonomic dysfunction, only one patient had orthostatic hypotension, impotence and bladder dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)