Tacalcitol in the treatment of acquired perforating collagenosis

Acquired perforating collagenosis (APC) is a rare perforating dermatosis characterized by transepidermal collagen elimination. We describe a 65-year-old patient, with long-standing type 2 diabetes mellitus and a 2-year history of itchy hyperkeratotic nodules situated on the back, who was subsequently diagnosed with APC. Treatment included topical corticosteroids and antihistamines, without improvement of the lesions. However, therapy with topical tacalcitol administered for 2 months produced a significant response leading to complete remission of APC.