Herpes simplex mimicking leukemia cutis

We present a patient with chronic lymphocytic leukemia who developed a painful penile ulcer that was initially diagnosed as leukemia cutis, as evidenced hy an atypical leukemic infiltrate on biopsy. A Tzanck preparation was positive for multinucleated giant cells, and the diagnosis of herpes genitalis was confirmed by viral culture. In patients with hematologic malignancies, herpes simplex virus must be included in the differential diagnosis of ulcerative lesions. The histopathologic findings of inflammatory dermatoses in these patients may include an atypical infiltrate, because of the predominance of atypical inflammatory cells in the peripheral circulation.