• herpes simplex virus;
  • immune compromise;
  • pemphigus vulgaris;
  • plasmacytic atypia

The clinical and histopathological features of cutaneous herpes simplex virus (HSV) infection have been well described. Genital herpetic infections are largely induced by HSV type 2, but 30% of cases can be caused by HSV type 1. Immunocompromised patients are known to exhibit atypical patterns of clinical presentation with variable lesion morphology and anatomic location. A subset of patients may show morphology such as nodules or verrucous lesions. Analogously, some biopsy specimens may show unusual microscopical features, such as a lack of keratinocyte cytopathology, lymphocyte infiltration or vasculopathic changes that are expected irrespective of the patient's immune status. We present the case of a patient carrying a previous diagnosis of pemphigus vulgaris, status posttreatment with methotrexate and prednisone, who developed a perineal ulcer exhibiting significant numbers of plasma cells, many of which were cytologically atypical. This morphology was suggestive of a hematopoietic malignancy. Immunoperoxidase staining for HSV decorated a focal collection of keratinocytes that lacked appreciable viral changes expected of HSV infection.

Boyd AS, Zwerner JP, Miller JL. Herpes simplex virus-induced plasmacytic atypia.