Pityriasis rosea (herald patch)

    Article Contributors: 
    Sean Klepper M.D.
    Artur Zembowicz M.D....

    Clinical Features:

     

    • Papulosquamous eruption of probable viral etiology primarily affecting children and young adults
    • A viral prodrome is followed by single large lesion known as a "herald patch."  Later, a more generalized rash develops in a "Christmas tree" distribution on the trunk.

    Histologic Features:

     

    • Spongiosis
    • The epidermis may be normal in thickness to mildly acanthotic.
    • Focal parakeratosis, sometimes with one end of the parakeratotic focus "tilting up"
    • Perivascular lymphocytic infiltrate with varying degrees of exocytosis
    • Dyskeratosis and red blood cell extravasation may sometimes be present.
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    Cases associated with this book:

  • Pityriasis rosea
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: DermatopathologyConsultations.com Teaching Collection