Reactive Perforating Collagenosis

Excerpt

Reactive perforating collagenosis (RPC), one of the perforating dermatoses, is a rare skin disease with a characteristic transepidermal elimination of altered collagen through the epidermis. It occurs in 2 forms: an inherited form in childhood that is rare and an acquired form in adulthood, more commonly found in patients with diabetes mellitus and end-stage renal disease. Commonly, patients will have hyperkeratotic papules on the extensor areas of extremities and hands, most likely over areas of superficial trauma. The lesions are very pruritic and can grow into large, umbilicated papulonodules with a central keratotic plug that relapse and remit throughout the patient’s lifetime. Most cases are self-limited and do not require treatment.