[Acquired reactive perforating collagenosis in diabetes mellitus]

A 70-year-old woman with type 2B diabetes mellitus was referred to the dermatology department because of inflammatory skin changes of unknown origin over the trunk and limbs. On admission follicular and parafollicular livid-red papulae with central crusts and reddened margins were noted over the lower legs and the lumbosacral region.

Further physical examination revealed no additional abnormalities. Erythrocyte sedimentation rate was 41/79 mm. The day-time blood-glucose profile was raised (10.2, 12.6 and 8.6 mmol/l), as was the glycosylated haemoglobin HbA1c (9.0%). Swabs from fresh lesions gave no evidence of fungal or bacterial infection. Biopsies revealed areas of widened epidermis with central ulceration filled with fibrin, granulocytes and collagen fibres.

The clinical and histological findings indicated an acquired reactive perforating collagenosis (dermatosis) which should be judged in relation to the long-standing diabetes mellitus. The cutaneous changes were covered with salicylate- and steroid-containing preparations, while individual lesions were excised or removed by curettage.

The condition of acquired reactive perforating collagenosis is, like Kyrle's disease (perforating follicular and parafollicular hyperkeratotic dermatosis), perforating serpiginous elastosis and perforating folliculitis classified among the perforating dermatoses. In the presence of renal failure and (or) diabetes mellitus these dermatoses must be thought of in the differential diagnosis, in addition to the more frequent pruriginous conditions, if there are corresponding skin changes.