Reactive perforating collagenosis associated with scabies in a diabetic.

Reactive perforating collagenosis (RPC) in adults commonly manifests in patients with diabetes mellitus. Pruritus and consequent induced scratching have been identified as the bases for the evolution of this skin disease. We present the unusual case of a 55-year-old female diabetic with characteristic umbilicated skin lesions and a long history of scabies. Histology from a crusty nodule revealed transepidermal elimination of collagen. Following antiscabietic treatment, two courses of oral doxycycline demonstrated beneficial effects in controlling the perforating skin disorder.