Skin Sympathetic Response In Subclinical Diabetic Neuropathy

Abstract

Skin sympathetic response (SSR)—a method of assessing sudomotor sympathetic fibres dysfunction—is absent in 9–83% of diabetic patients with distal symmetrical sensorimotor neuropathy (1,2). There are only few reports in the literature about SSR in subclinical stages of diabetic neuropathy. We therefore measured SSR in 73 diabetic patients (49 patients with clinically evident diabetic neuropathy/assessed with pin prick test, light touch, 128 Hz tuning fork, ankle reflexes and 10 g monofilament/ and 24 patients without clinical signs of diabetic neuropathy, but with abnormal conduction studies of nervus suralis and peroneus) and 32 normal subjects at both feet and hands. We considered the SSR abnormal only when it was absent in two or more extremities. SSR was present in all normal subjects in all extremities (100%). SSR was absent in 47% of the whole group of diabetic patients. It was absent in 34.7% of the subgroup of patients with clinically evident diabetic neuropathy, and 20.8% in the subgroup without clinical signs of neuropathy. These differences were not statistically significant. Our results support the observations of higher vulnerability and early involvement of small unmyelinated peripheral sympathetic fibres in diabetes mellitus. We conclude, that measuring of SSR can be helpful in diagnosis of subclinical diabetic neuropathy and can extend spectrum of electrophysiological diagnostic methods.1. Soliven B, Maselli R, Jaspan J, Green A, Graziano H, Petersen M, Spire J‐P: Sympathetic skin response in diabetic neuropathy. Muscle Nerve 10, 1987: 711–716.2. Niakan E, Harati Y: Sympathetic skin response in diabetic peripheral neuropathy. Muscle Nerve 2, 1988: 261–264.