Nodular perianal herpes simplex with prominent plasma cell infiltration

Nodules are exceptional manifestations of herpes simplex virus (HSV) infection in immunocompromised patients. Only two cases of nodular HSV-2 infection of the perianal region have been reported previously.

The case of a 46-year-old homosexual man with AIDS presenting with painful perianal nodules resembling squamous cell carcinoma is described.

This case report presents details of the histologic findings and treatment regimen.

Histologic examination showed the presence of rare multinucleated giant epithelial cells and a dense inflammatory infiltrate composed mostly of plasma cells. Polymerase chain reaction analysis was positive for HSV-2 and negative for HSV-1, cytomegalovirus, Epstein-Barr virus, and human herpesvirus types 6 and 7. After being treated ineffectively with oral acyclovir (4 g/d) for 15 days, the patient was treated with oral valacyclovir (6 g/d), resulting in marked improvement in 10 days and complete resolution after 2 months.

In immunocompromised patients, HSV-2 infection may present with atypical clinical and histopathological features.