A case report of superficial necrolytic dermatitis in a beagle dog with diabetes mellitus.

A case of superficial necrolytic dermatitis in a young laboratory beagle dog with diabetes mellitus was investigated. Macroscopically, the skin lesion was restricted to paws showing erosion and swelling of the interdigital areas. The most predominant histopathological feature was upper-epidermal vacuolation of keratinocytes. In the pancreas, the number and size of islets were found to be markedly reduced, and only glucagon-positive cells were detected. In the liver, severe and widespread vacuolation of hepatocytes was observed. Blood biochemical assays showed that the serum glucose and plasma glucagon levels were increased. In addition, levels of individual amino acids varied markedly, although the total amino acid concentration was within the normal range. From these results, it was suggested that the skin lesion in this case was primarily caused by hyperglucagonemia in diabetes mellitus.