Fast Five Quiz: Herpes Zoster Facts vs Fiction

William James, MD


September 22, 2021

The thoracic dermatome is most commonly involved in herpes zoster, followed by the cervical and trigeminal dermatomes. Lesions are typically unilaterally distributed within a single dermatome. Rarely, herpes zoster manifests bilaterally. Bilateral presentations should always raise concern for disseminated disease (and immunocompromise) or for an alternate diagnosis, specifically herpes simplex.

Symptoms typically include prodromal sensory phenomena along one or more skin dermatomes; these are usually noted as pain or, less commonly, itching or paresthesias. After the onset of prodromal symptoms, the following signs and symptoms occur:

  • Patchy erythema, occasionally accompanied by induration, develops in the dermatomal area of involvement.

  • Regional lymphadenopathy occurs either at this stage or subsequently.

  • Grouped herpetiform vesicles develop on the erythematous base (the classic finding).

  • Pain in the dermatomal area of involvement may remain the same as in prodrome or may change in character and intensity with the onset of other symptoms. Many patients describe the pain as burning, throbbing, or stabbing in nature. It may be severe, mild, constant, rare, or felt as another sensation such as pruritus. The involved area may be tender to palpation.

  • Vesicles are initially clear but eventually cloud, rupture, crust, and involute, a process that may be greatly accelerated by treatment.

  • After vesicular involution, slow resolution of the remaining erythematous plaques occurs, typically without visible sequelae. However, scarring can occur if deeper epidermal and dermal layers have been compromised by excoriation, secondary infection, or other complications.

Read more about the presentation of herpes zoster.


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