Clinical Manual > Diseases > Herpes Zoster/Shingles

Herpes Zoster/Shingles

July 2006

Chapter Contents

Background

Shingles is a skin or mucosal infection caused by the varicella-zoster virus (VZV) that occurs along a dermatome and represents a reactivation of varicella (chickenpox). Zoster is common in patients with HIV infection, including apparently healthy individuals before the onset of other HIV-related symptoms. The incidence may be higher at low CD4 cell counts and also within 4 months of initiating effective antiretroviral therapy.

Zoster may be particularly painful or necrotic in HIV-infected individuals. Disseminated infection, defined as outbreaks with >20 vesicles outside the primary and immediately adjacent dermatomes, usually involves the skin and the visceral organs. Neurologic complications of zoster include encephalitis, transverse myelitis, and vasculitic stroke.

S: Subjective

The patient complains of painful skin blisters or ulcerations along 1 side of the face or body. Loss of vision may accompany the appearance of facial lesions. Pain in a dermatomal distribution may precede the appearance of lesions by many days (prodrome).

Assess the following during the history:

Duration of pain or blisters (average of 2-3 weeks if untreated)
Location of pain or blisters; severity of pain
History of chickenpox (usually in childhood)

O: Objective

Perform a skin and neurologic examination to include the following:

Vesicular lesions with erythematous bases in a dermatomal distribution; may be bullous or hemorrhagic
Necrotic lesions; may persist for as long as 6 weeks
Dermatomal scarring (particularly in dark-skinned individuals)
Lesions in the eye area or tip of nose, along the trigeminal nerve; these represent ophthalmic nerve involvement, which requires immediate evaluation and intravenous treatment (see below)

A: Assessment

Rule out other causes of vesicular skin eruptions (eg, herpes simplex virus, severe drug reactions).
Assess contact exposures (see below).

P: Plan

Diagnostic Evaluation

The diagnosis is usually clinical and is based on the characteristic appearance and distribution of lesions. If the diagnosis is uncertain, perform viral cultures or antigen detection by direct fluorescent antibody from a freshly opened vesicle or biopsy from the border of a lesion.

Treatment

Treatment ideally should begin within 72 hours of an outbreak or while new lesions are appearing. Famciclovir (Famvir) 500 mg orally 3 times per day for 7-10 days or valacyclovir (Valtrex) 1 g orally every 8 hours for 7 days is the preferred regimen and may attenuate a herpes/VZV attack if started early.
An alternative treatment is acyclovir 800 mg orally 5 times per day.
Dosage reductions of these drugs are required for patients with renal impairment.
If new blisters are still appearing at the end of treatment, repeat course of oral therapy or consider intravenous treatment. Adjunctive corticosteroids aimed at preventing postherpetic neuralgia are not recommended.
Consult an ophthalmologist immediately if lesions appear in the eye area or on the tip of the nose, or if patient complains of visual disturbances, because VZV-related retinal necrosis can cause blindness. Because of the rapid progression associated with this diagnosis, hospitalization for intravenous acyclovir and possibly foscarnet is recommended.
VZV from zoster lesions is contagious, and contact or airborne spread from vesicle fluid may cause chickenpox in nonimmune people. If a zoster patient's household includes a pregnant woman (HIV infected or uninfected) or an HIV-infected child, consult with a specialist immediately for advice on management of exposed household members. (See " Postcontact Chickenpox Prevention " below.)
Give analgesics for pain; narcotics may be required.
Antiviral therapy may reduce the risk of postherpetic neuralgia, but if it does occur, special pain control techniques will be required:
- Nortriptyline 10-20 mg should be taken every night at bedtime and increased until pain is controlled and adverse effects remain tolerable. Other tricyclics may be used.
- Lidocaine 5% patches provide good local relief with minimal systemic absorption. Up to 3 patches may be applied simultaneously to the affected area for up to 12 hours in a 24-hour period.
- Gabapentin is given at 100-300 mg orally 3 times per day; this may be increased until reaching 3,600-mg total daily dosage.
- Sustained-release opiates may be required.

(See chapter Pain Syndrome and Peripheral Neuropathy for more options and specific recommendations.)

Severe or unresponsive cases

Intravenous acyclovir may be indicated if:
- The patient is severely immunocompromised
- The ophthalmic branch of the trigeminal nerve is affected (as noted above)
- Dissemination has occurred
- Lesions are not responsive to oral therapy
- Pain is intractable
The usual adult dosage is 10-12 mg/kg every 8 hours for 7-14 days; dosage reduction is required for patients with renal impairment. Refer to an infectious disease specialist.
Acyclovir resistance may occur in patients previously treated with acyclovir or related drugs, and foscarnet may be required for effective treatment. Resistance should be suspected if lesions are not resolving after 10 days of therapy or if they develop a verrucous appearance. Such lesions should be cultured and drug sensitivities should be obtained.

Postcontact Chickenpox Prevention

All persons, including pregnant women, who have close contact with a patient who has chickenpox or shingles must be treated to prevent chickenpox. Those who have no history of chickenpox or shingles or no detectable antibody against VZV should be administered varicella zoster immune globulin as soon as possible, but at least within 96 hours after contact. Even immunocompetent adults with primary VZV (chickenpox) can develop viral dissemination to the visceral organs. HIV-infected patients may develop encephalitis, pneumonia, or polyradiculopathy during primary zoster (chickenpox) or reactivated zoster (shingles).

Patient Education

Patients should bathe the skin lesions in mild soap and water. For necrotic lesions, patients should use warm, moist compresses 2-3 times a day to remove debris.
Antibiotic ointments may help prevent secondary infection and keep dressings from sticking.
Advise patients to take their medications as directed, and to call the clinic if symptoms worsen.

References

Anon. An improving outlook for patients with post-herpetic neuralgia . Drugs and Therapy Perspectives, 2001; 17(13)8-11.

Bartlett JG, Gallant JE. 2005-2006 Medical Management of HIV Infection . Baltimore: Johns Hopkins University Division of Infectious Diseases; 2005. Available online at hopkins-aids.edu/mmhiv/order.html.

Centers for Disease Control and Prevention, National Institutes of Health, Infectious Diseases Society of America. Treating Opportunistic Infections Among HIV-Exposed and Infected Children: Recommendations from CDC, the National Institutes of Health, and the Infectious Diseases Society of America . MMWR Recomm Rep. 2004 Dec 3; 53(RR14);1-63. Available online at aidsinfo.nih.gov/Guidelines/GuidelineDetail.aspx?GuidelineID=14. Accessed May 19, 2006.

Centers for Disease Control and Prevention, National Institutes of Health, HIV Medicine Association/Infectious Diseases Society of America. Treating Opportunistic Infections Among HIV-Infected Adults and Adolescents . MMWR Recomm Rep. 2004 Dec 17; 53(RR15);1-112. Available online at aidsinfo.nih.gov/Guidelines/GuidelineDetail.aspx?GuidelineID=14. Accessed May 19, 2006.

Erlich K. Herpes Simplex Virus and HIV . In: Peiperl L, Coffey S, Volberding PA, eds. HIV InSite Knowledge Base [textbook online]; San Francisco: UCSF Center for HIV Information; June 2003. Accessed February 7, 2006.

McCrary ML, Severson J, Tyring SK. Varicella zoster virus . J Am Acad Dermatol. 1999; 41(1):1-14.

Copyright 2010, the AIDS Education & Training Centers National Resource Center, unless otherwise noted. All rights reserved. Email webmaster@aidsetc.org with questions, comments, or problems. See disclaimer for usage guidelines.