Derm Dx: Denuded, crusted patches on the lower lip

A patient, aged 46 years, presented with denuded and crusted patches on his lower lip. The condition had waxed and waned in intensity over the past three years and has not responded to a three-week course of topical fluocinonide ointment.

When flared, the patient reported the condition was extremely painful. The patient tested positive for hepatitis C. He smoked cigarettes until ...