Association between "diabetic thick skin syndrome" and neurological disorders in diabetes mellitus.

Skin thickness on the extremities of patients with diabetes mellitus has been described controversially. Using high resolution ultrasonography, we were able to show a significant increase in skin thickness at the forearm (P < 0.05), thigh (P < 0.001) and lower limb (P < 0.05) of diabetic patients, most prominent at the thigh. No difference in skin thickness was found at the dorsum of the foot. In addition, skin thickness was not related to the duration of diabetes, age or HbA1. A close association was found between diabetic neuropathy and increasing skin thickness. Diabetic patients with neurological disorders had a significant increase in skin thickness versus diabetic patients without neuropathy. The present findings suggest that diabetic neuropathy and abnormalities of connective tissue have a common etiological link in their development or that both are time-dependent processes. Whether changes in capillary blood flow, increase of nonenzymatic glycosylation, polyol accumulation or other metabolic disorders are responsible for these findings remains still to be established.