Herpes zoster

    Clinical Features:

    • Caused by viral reactivation in patients previously infected by varicella zoster virus (VZV)
    • Painful vesicles on an erythematous base in the distribution of a sensory dermatome
    • Most often seen in elderly and immunocompromised individuals
    • Immunocompromised patients are at risk for disseminated infection.

    Histologic Features:

    • The changes are identical to those seen in varicella and herpes simplex:
      • "Steel gray" keratinocyte nuclei
      • Multinucleated keratinocytes with margination of chromatin ("pomegranates")
      • Eosinophilic nuclear inclusions surrounded by clear haloes
      • Intracellular edema and ballooning degeneration
      • Acantholysis
      • Intraepidermal vesiculation
      • Dense dermal lymphocytic inflammation
      • Sometimes inflammation of nerve twigs and/or vasculitis is seen.
    • Immunocompromised patients may have marked necrosis of the epidermis and widespread involvement of adnexal structures.
    External Links:

    Herpes zoster folliculitis:

    Clinical Features:

    • Herpes simplex and herpes zoster virus do not typically involve the hair follicles, but may occasionally do so, particularly in early infection.
    • Lesions may be especially widespread and severe in immunocompromised patients.

    Histologic Features:

    • Viral cytopathic effects may be seen within the hair follicles: dysmaturation, acantholysis, dyskeratosis, multinucleate keratinocytes.
    • There may be focal to extensive necrosis of the hair follicle.
    • The dermis shows dense perivascular and sometimes perineural lymphocytic infiltrates, in some cases with atypia that may mimic lymphoma.

     

    Cases associated with this book:

  • Herpes zoster folliculitis
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: DermatopathologyConsultations.com Teaching Collection