PT - JOURNAL ARTICLE AU - Gonçalo Pereira Cruz AU - Cristina Fonseca AU - Joaquim Oliveira AU - José Saraiva da Cunha TI - Acute retinal necrosis by herpes simplex virus type 1: an unusual presentation of a primary infection AID - 10.1136/bcr-2019-232566 DP - 2019 Dec 01 TA - BMJ Case Reports PG - e232566 VI - 12 IP - 12 4099 - http://casereports.bmj.com/content/12/12/e232566.short 4100 - http://casereports.bmj.com/content/12/12/e232566.full SO - BMJ Case Reports2019 Dec 01; 12 AB - 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.