Histological findings in clinically normal skin of patients with insulin-dependent diabetes.

Biopsies of clinically normal skin of 22 young patients with insulin-dependent diabetes of varying duration ( > 10 years, n= 12; <5 years, n= 10) were examined using a panel of histological stains, and compared with those of 10 non-diabetic control subjects of similar age. Abnormalities under light microscopy were scored for severity. Scores for both groups of diabetics were significantly greater than scores for controls (P<0.001). Increased upper dermal vasculature and PAS positivity of blood vessel walls were more frequent in diabetic skin than in controls, and increased with duration of disease. PAS positivity was caused in part by deposition of glycogen in endothelial cells. Clumping of elastic fibres in the upper dermis was observed in seven of the 22 skin biopsies from diabetic patients, but not in control biopsies. An inflammatory infiltrate was more frequent in diabetic skin. No association was demonstrated between the histological scores and the presence of diabetic retinopathy, or the concentration of glycosylated haemoglobin in the diabetic subjects. None of the histological features was specific to diabetic skin. [ABSTRACT FROM AUTHOR]