HSV ΙΝFECTION WITH ABUNDANT EXTRACELLUAR INCLUSION BODIES IN A PATIENT WITH ACUTE MYELOID LEUKEMIA

Summary: The histopathologic presentation of HSV infection is often very distinctive. The typical lesion is of an intraepidermal vesicle with acantholytic and necrotic keratinocytes within the blister. Infected keratinocytes show nuclear changes such as margination of the nuclear chromatin, multinucleation and nuclear inclusions. We report a case of an unusual histopathologic presentation of HSV infection with abundant free viral particles in a patient with a history of AML. The 45-year-old patient presented with a large perirectal ulcerated lesion and a recent hospitalization for bacteremia. A punch biopsy was performed to rule out leukemia cutis. The sections revealed prominent tissue necrosis beneath the ulcer and a dense lymphohistiocystic infiltrate. Throughout the necrotic dermis, there were scattered light pink homogenous particles with an associated sparse mixed inflammatory cell infiltrate. Immunohistochemical (IHC) studies revealed that these particles were positive for both HSV-1 and HSV-2. VZV, CMV, PAS and AFB were negative. There was no diagnostic evidence of involvement by hematolymphoid neoplasm. Unlike the usual intraepidermal blister presentation, this case emphasizes an unusual histopathologic presentation of abundant extracellular HSV inclusion bodies that may be seen in immunocompromised patients. IHC staining is confirmative of the presence of specific viral antigens. The etiology will be discussed.