Necrobiosis lipoidica diabeticorum: a clinicopathologic study.

Necrobiosis lipoidica diabeticorum is an unusual dermatologic condition with a characteristic clinical appearance and a clear association with diabetes mellitus. There is currently no treatment that reverses the atrophic changes associated with this lesion. We have carried out a clinicopathologic study on 15 subjects and, in addition, have reviewed 10 further biopsy specimens of necrobiosis lipoidica diabeticorum. We found a frequent association of necrobiosis lipoidica diabeticorum with other chronic complications of diabetes mellitus, including limited joint mobility. It is possible that nonenzymatic glucosylation or other changes in collagen may be important in the etiology of necrobiosis lipoidica diabeticorum and the limited joint mobility. We confirmed that cutaneous anesthesia is usually present in the necrobiosis lipoidica diabeticorum lesions. With the use of an antibody to S100 protein and an immunohistochemical method, there was an apparent decreased number of nerves in the skin lesions. We suggest that sensory loss results from local destruction of cutaneous nerves by the inflammatory process. Finally, in six elliptical biopsies extending into clinically normal skin, we demonstrated that the inflammatory infiltrate of necrobiosis lipoidica diabeticorum extended from the lesion into apparently normal skin surrounding clinically active lesions. Thus, intradermal steroids might be administered to perilesional areas surrounding active lesions in the hope of halting progression.