Acute retinal necrosis by herpes simplex virus type 1: an unusual presentation of a primary infection.

Herpes simplex virus (HSV) can affect the central nervous system causing meningitis, encephalitis and, rarely, acute retinal necrosis. We present a case of a 46-year-old man, previously healthy complaining of a 5-day persistent headache and sudden loss of vision of his left eye that progressed to the right. We started ceftriaxone, methylprednisolone and acyclovir for suspected encephalitis with vasculitis. HSV-1 was identified in vitreous and aqueous humour. Therapy with acyclovir was maintained and two intravitreous boluses of foscarnet were administered, without improvement. Usually being a benign infection, HSV can, in rare cases like this, have catastrophic effects in the optic tract.