Herpes zoster is a dermatomal, unilateral reactivation of the varicella zoster virus. All ages, including infants, can be affected. The eruption may occur anywhere but most commonly occurs on the face and trunk. Pruritus, pain, tenderness, and dysesthesias may present 4 to 5 days prior to an eruption composed of umbilicated, grouped vesicles on an erythematous, edematous base. The vesicles may become purulent or hemorrhagic. Occasionally, nerve involvement may occur without cutaneous involvement. Rare presentations involve multiple dermatomes or cross midline. Ophthalmic zoster (see related item) involves the nasociliary branch of the 5th cranial nerve and presents with vesicles on the nose and cornea (Hutchinson sign). Ramsay Hunt syndrome (see related item) is a herpes zoster infection of the geniculate ganglion with tinnitus, decreased hearing, facial palsy, and vesicles on the tympanic membrane, pinna, and ear canal.
Management and Disposition
Antiviral medication (acyclovir, famciclovir, or valacyclovir) hastens healing. If started within 72 hours of vesicle appearance, the duration, intensity, and associated pain are significantly decreased (benefit seen at least up to 7 days after vesicle appearance).
Admission for IV acyclovir is usually reserved for complicated cases involving multiple dermatomal distributions, involvement of the ophthalmic branch of the trigeminal nerve, disseminated disease, or immunocompromised patients. Herpes zoster keratitis requires emergent ophthalmologic consultation to avoid any potential scarring or vision loss.
Herpes Zoster. Dermatomal distribution of vesicles and crusted erosions. (Photo contributor: Department of Dermatology, Wilford Hall USAF Medical Center and Brooke Army Medical Center, San Antonio, TX.)
Herpes Zoster. Trigeminal nerve (V1) dermatomal distribution with upper eyelid involved; ophthalmologic evaluation is needed to rule out corneal involvement. (Photo Contributor: Kevin J. Knoop, MD, MS.)
Herpes Zoster. Unilateral T4 distribution with grouped erythematous vesicles. (Photo Contributor: Kevin J. Knoop, MD, MS.)
Avoid contact with nonimmune or immunocompromised contacts from the prodrome stage until complete reepithelialization of the lesions.
Herpes zoster during pregnancy confers no risk to a healthy mother or fetus (as opposed to primary varicella virus infection, which causes morbidity and mortality in both mother and fetus).
Postherpetic neuralgia (intense, chronic pain in the affected dermatome) affects 10% to 20% of patients and is more common with advancing age, family history, and immunosuppression.
Immunocompromised patients can have unusual presentations with diffuse cutaneous and visceral involvement.