MSFinals-0713

A 50-year-old man presents to his physician with a complaint of excessive dandruff. He also reports the presence of scaling lesions on his face. Upon examination, there is waxing scale with underlying erythema on his eyebrows, scalp, and nasolabial fold. The patient has a history of HIV for the past 3 years and is currently taking retroviral medication. What is the most probable diagnosis?