Herpes simplex virus lymphadenitis: the elusive doppelganger in immunocompromised patients.

Herpes simplex virus has protean manifestations and is an important cause of morbidity in the immunocompromised host. We report a case of recurrent lymphadenopathy and rash in a patient with chronic lymphocytic leukemia. The elusive clinical diagnosis eventually required core biopsy of a lymph node with immunohistochemistry and confirmation by polymerase chain reaction. This case illustrates the challenging clinical and laboratory diagnosis of herpes simplex virus lymphadenitis and the need to maintain a high index of suspicion for infection when treating an immunocompromised patient with unusual and/or persistent symptoms.