Cases from the Osler Medical Service at Johns Hopkins University. Herpetic keratitis

Presenting features

A 38-year-old man with a history of intravenous drug use was admitted to the hospital for treatment of an arm abscess. He noted that his right eye was “blood shot” and painful, but denied recent ocular trauma. He had photophobia and felt that his vision had become worse. Physical examination revealed a red right eye; there was hyperemia of the conjunctiva without surrounding vesicles, and the cornea was cloudy (Figure 1). Visual acuity was normal in the left eye but decreased (20/200) in the right eye. Fundoscopic examination was otherwise unremarkable. The rest of the physical examination was normal except for a tender painful swelling and cellulitis on the left forearm. Laboratory findings revealed antibodies to human immunodeficiency virus (HIV).What is the diagnosis?