Painful Red Eye

A 27-year-old man presented to the emergency department (ED) with a complaint of left eye pain and redness for three days. The eye was initially watery and pruritic and a day later had become completely red and painful. He had no vision changes or antecedent trauma and denied any constitutional or upper respiratory symptoms. Vital signs were normal. The left upper eyelid showed ecchymosis. Pupils were equal and reactive. Visual acuity was 20/25 in both eyes. There was no fluorescein uptake and the remainder of the slit lamp exam was unremarkable.