Severe complications of herpes zoster.

The usual presentation of herpes zoster is as a self-limiting vesicular rash, often accompanied by post-herpetic neuralgia (PHN), its most common complication. However, herpes zoster can give rise to other complications, many of which have unusual presentations and serious sequelae. The incidence and burden of many of these less common complications are poorly understood. Ocular complications of ophthalmic zoster are relatively frequent but, with early antiviral therapy, need not be sight-threatening. Delayed contralateral hemiparesis is a rare complication of ophthalmic zoster that may present as stroke, temporally remote from the zoster episode. Ramsay Hunt syndrome is caused by reactivation of varicella zoster virus (VZV) involving the facial nerve; facial paralysis, ear pain and vesicles in the ear are diagnostic. Facial paralysis in the absence of vesicles may indicate zoster sine herpete, which can be mistaken for Bell's palsy. Herpetic facial palsies may respond to combination therapy with an antiviral plus steroid, but further research is needed to determine the benefit of such treatments.