Middle-aged man seen for 3 days of aching eye pain and blurred vision

A 53-year-old HIV-positive man was admitted to Tufts Medical Center for 3 days of worsening periocular pain and blurred vision in his left eye.Initially, he noticed mild swelling of the left upper eyelid associated with an ipsilateral aching pain when he looked in left lateral gaze. As the pain worsened, he also noticed blurred vision in the left eye. He denied sinusitis or symptoms of an upper respiratory infection, nasal or ocular discharge, diplopia or headaches. He also noted that for the last “few days” he had “not felt well,” including feeling “unsteady” on his feet. He denied any fevers or chills. His CD4 count was within normal limits, and his viral load was undetectable.