> Table of Contents > Herpes Zoster (Shingles)
Herpes Zoster (Shingles)
Robert J. Hyde, MD, MA, NRP, FACEP
image BASICS
DESCRIPTION
  • Results from reactivation of latent varicella-zoster virus (human herpesvirus type 3) infection
  • Postherpetic neuralgia (PHN) is defined as pain persisting at least 1 month after rash has healed. The term zoster-associated pain is more clinically useful.
  • Usually presents as a painful unilateral vesicular eruption with a dermatomal distribution
  • System(s) affected: nervous; integumentary; exocrine
  • Synonym(s): shingles
EPIDEMIOLOGY
Predominant sex: male = female
Incidence
  • Incidence increases with age. 2/3 of cases occur in adults age ≥50 years. Incidence is increasing overall as the U.S. population ages.
  • Herpes zoster: 4/1,000 person-years (1)
  • PHN: 18% in adult patients with herpes zoster; 33% in patients ≥79 years of age
Prevalence
Nearly 1 million new cases of herpes zoster annually
Pregnancy Considerations
May occur during pregnancy
Geriatric Considerations
  • Increased incidence of zoster outbreaks
  • Increased incidence of PHN
Pediatric Considerations
  • Occurs less frequently in children
  • Has been reported in newborns infected in utero
ETIOLOGY AND PATHOPHYSIOLOGY
Reactivation of varicella-zoster virus from dorsal root/cranial nerve ganglia. Upon reactivation, the virus replicates within neuronal cell bodies, and virions are carried along axons to dermatomal skin zones, causing local inflammation and vesicle formation.
RISK FACTORS
  • Increasing age
  • Immunosuppression (malignancy or chemotherapy)
  • HIV infection
  • Use of immunosuppressant drugs (e.g., following organ transplant surgery)
  • Spinal surgery
GENERAL PREVENTION
  • Herpes zoster vaccination (Zostavax) is recommended by Advisory Committee on Immunization Practices (ACIP) for patients ≥60 years (FDA-approved for patients >50 years) (2,3,4):
    • Vaccine reduces cases of zoster and the incidence of PHN (5,6).
  • Patients with active zoster may transmit disease-causing varicella virus (chickenpox) to susceptible persons.
COMMONLY ASSOCIATED CONDITIONS
Immunocompromised individuals, HIV infection, posttransplantation, immunosuppressive drugs, and malignancy
image DIAGNOSIS
PHYSICAL EXAM
  • Acute phase
    • Rash: initially erythematous and maculopapular; evolves rapidly to grouped vesicles
    • Vesicles become pustular and/or hemorrhagic in 3 to 4 days.
    • Weakness (1% have weakness in distribution of rash)
    • Resolution of rash, with crusts separating by 14 to 21 days
  • Possible sine herpete (zoster without rash) and other chronic disorders associated with varicellazoster virus without the typical rash
    • Herpes zoster ophthalmicus (HZO). Vesicles on tip of the nose (Hutchinson sign) indicate involvement of the external branch of cranial nerve V; associated with increased incidence of ocular zoster.
  • Chronic phase
    • PHN (15% overall; increases with age)
    • A small percentage (1-5%) may affect the motor nerves, causing weakness (zoster motorius); facial nerve (e.g., Ramsay Hunt syndrome); spinal motor radiculopathies.
DIFFERENTIAL DIAGNOSIS
  • Rash
    • Herpes simplex virus
    • Coxsackievirus
    • Contact dermatitis
    • Superficial pyoderma
  • Pain
    • Cholecystitis
    • Appendicitis
    • Nephrolithiasis
    • Pleuritis
    • Myocardial infarction
    • Diabetic neuropathy
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
Rarely necessary because clinical appearance is sufficiently distinctive
Follow-Up Tests & Special Considerations
  • Viral culture
  • Tzanck smear (does not distinguish from herpes simplex, and false-negative results occur)
  • Polymerase chain reaction
  • Immunofluorescent antigen staining
  • Varicella-zoster-specific IgM
Test Interpretation
  • Multinucleated giant cells with intralesional inclusion
  • Lymphatic infiltration of sensory ganglia with focal hemorrhage and nerve cell destruction
image TREATMENT
GENERAL MEASURES
  • Treatment is directed to control symptoms and prevent complications.
  • Antiviral therapy decreases viral replication, lessens inflammation and nerve damage, and reduces the severity and duration of long-term pain.
  • Prompt analgesic control may shorten the duration of zoster-associated pain.
  • Lotions, such as calamine and colloidal oatmeal, may help reduce itching and burning sensation.
MEDICATION
First Line
  • Acute treatment
    • Antiviral agents initiated within 72 hours of skin lesions help relieve symptoms, speed resolution, and prevent or mitigate PHN (7)[A].
    • Valacyclovir: 1,000 mg PO TID for 7 days
    • Famciclovir: 500 mg PO TID for 7 days
    • Acyclovir: 800 mg q4h (5 doses daily) for 7 days
  • Analgesics (acetaminophen, NSAIDs)
  • Corticosteroids given acutely during zoster infection do not prevent PHN (8).
    • Tricyclic antidepressants (TCAs; amitriptyline 25 mg at bedtime and other low-dose TCAs) relieve pain acutely and may reduce pain duration; dose may be titrated up to 75 to 150 mg/day as tolerated.
    • Lidocaine patch 5% (Lidoderm) applied over painful areas (limit 3 patches simultaneously or trim a single patch) for up to 12 hours may be effective.
    • Gabapentin: 100 to 600 mg TID for pain and other quality-of-life indicators; limited by adverse effects
    • P.479

    • Capsaicin cream and other analgesics may be useful adjuncts. Use opioids sparingly.
    • Pregabalin: 50 to 100 mg TID reduces pain, but usefulness is limited by side effects.
  • Prevention of PHN and zoster-associated pain: No treatment has been shown to prevent PHN completely, but treatment may shorten duration and/or reduce severity of symptoms (9)[A].
    • Antiviral therapy with valacyclovir, famciclovir, or acyclovir given during acute skin eruption may decrease the duration of pain.
    • Low-dose amitriptyline (25 mg at bedtime) started within 72 hours of rash onset and continued for 90 days may reduce PHN incidence/duration.
    • Insufficient evidence to suggest that corticosteroids reduce incidence, severity, or duration of PHN (8)
  • Precautions
    • Assess renal function prior to using valacyclovir, famciclovir, or acyclovir.
    • Valacyclovir, famciclovir, and acyclovir are pregnancy Category B.
Second Line
Numerous therapies have been advocated, but supporting evidence to routinely recommend is lacking.
COMPLEMENTARY & ALTERNATIVE MEDICINE
Studies on cupping therapy (traditional Chinese medicine) show potential benefit, but evidence is conflicting (10)[A].
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
Outpatient treatment, unless disseminated or occurring as complication of serious underlying disease requiring hospitalization
image ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Referral to ophthalmology if concern for involvement of ophthalmic branch of the trigeminal nerve
Patient Monitoring
Follow duration of symptoms—particularly PHN. Consider hospitalization if symptoms are severe; patients are immunocompromised; >2 dermatomes are involved; serious bacterial superinfection, disseminated zoster, or meningoencephalitis develops.
DIET
No special diet
PATIENT EDUCATION
  • The duration of rash is typically 2 to 3 weeks.
  • Encourage good hygiene and proper skin care.
  • Warn of potential for dissemination (dissemination must be suspected with constitutional illness signs and/or spreading rash).
  • Warn of potential PHN.
  • Warn of potential risk of transmitting illness (chickenpox) to susceptible persons.
  • Seek medical attention if any eye involvement.
PROGNOSIS
  • Immunocompetent individuals should experience spontaneous and complete recovery within a few weeks.
  • Acute rash typically resolves within 14 to 21 days.
  • PHN may occur in patients despite antiviral treatment.
REFERENCES
1. Yawn BP, Saddier P, Wollan PC, et al. A population-based study of the incidence and complication rates of herpes zoster before zoster vaccine introduction. Mayo Clin Proc. 2007;82(11):1341-1349.
2. Hales CM, Harpaz R, Ortega-Sanchez I, et al. Update on recommendations for use of herpes zoster vaccine. MMWR Morb Mortal Wkly Rep. 2014;63(33):729-731.
3. Schmader KE, Levin MJ, Gnann JW Jr, et al. Efficacy, safety, and tolerability of herpes zoster vaccine in persons aged 50-59 years. Clin Infect Dis. 2012;54(7):922-928.
4. Harpaz R, Ortega-Sanchez IR, Seward JF, et al. Prevention of herpes zoster: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2008;57(RR-5):1-30.
5. Chen N, Li Q, Zhang Y, et al. Vaccination for preventing postherpetic neuralgia. Cochrane Database Syst Rev. 2011;(3):CD007795.
6. Langan SM, Smeeth L, Margolis DJ, et al. Herpes zoster vaccine effectiveness against incident herpes zoster and post-herpetic neuralgia in an older US population: a cohort study. PLoS Med. 2013;10(4):e1001420.
7. McDonald EM, de Kock J, Ram FS. Antivirals for management of herpes zoster including ophthalmicus: a systematic review of highquality randomized controlled trials. Antivir Ther. 2012;17(2):255-264.
8. Chen N, Yang M, He L, et al. Corticosteroids for preventing postherpetic neuralgia. Cochrane Database Syst Rev. 2010;(12):CD005582.
9. Li Q, Chen N, Yang J, et al. Antiviral treatment for preventing postherpetic neuralgia. Cochrane Database Syst Rev. 2009;(2):CD006866.
10. Cao H, Li X, Liu J. An updated review of the efficacy of cupping therapy. PLoS One. 2012;7(2):e31793.
See Also
&NA;
  • Bell Palsy; Chickenpox (Varicella Zoster); Herpes Eye Infections; Herpes Simplex
  • Algorithm: Genital Ulcers
Codes
&NA;
ICD10
  • B02.9 Zoster without complications
  • B02.29 Other postherpetic nervous system involvement
Clinical Pearls
&NA;
  • Zoster vaccine is recommended for patients ≥60 years of age and is approved for patients >50 years.
  • Patients with herpes zoster should begin antiviral therapy within 72 hours of the onset of rash to be most effective.
  • Patients with active herpes zoster can transmit clinically active disease (chickenpox) to susceptible individuals.