Herpes zoster ophthalmicus (HZO) is a neurocutaneous disease caused by reactivation of herpes zoster infection from latent phase after varicella infection in elderly population. It affects ophthalmic division of trigeminal nerve. Common ocular presentation includes conjunctivitis, anterior uveitis, and keratitis. Orbital apex syndrome rarely occurs as a complication of herpes zoster ophthalmicus in young human immunodeficiency virus (HIV)-positive men.
A 20-year-old, recently diagnosed HIV-positive man, presented with vesicular skin rashes over right periorbital and forehead area, associated with right eye redness. He was treated as herpetic zoster ophthalmicus with oral antiviral (acyclovir). Three days later, he developed right eye ptosis, reduced visual acuity, anisocoria, and total ophthalmoplegia. An orbit magnetic resonance imaging showed swelling of all rectus muscles of right eye with right optic nerve perineural enhancement. Diagnosis of right eye herpes zoster ophthalmicus with orbital apex syndrome was established, and intravenous acyclovir was initiated. Systemic antiviral acyclovir continued for up to 10 days. Upon discharge, his ocular features improved; however, his visual impairment persisted.
Orbital apex syndrome is a rare complication of herpes zoster ophthalmicus. This irreversible sight- threatening complication can be prevented by early diagnosis of HZO and immediate starting of anti­viral treatment.