Herpes Simplex Virus Necrotic Lymphadenitis Masquerading as Lymphoma

In immunocompromised patients, the rapid development of lymphadenopathy could pose a few diagnostic challenges. This is important, especially with chronic lymphocytic leukemia and small lymphocytic lymphoma (CLL/SLL) which can manifest with the development of infections or may even progress with transformation into a more aggressive form of the disease. We report a case of a patient with CLL/SLL who presented with fever and worsening dyspnea as well as inguinal lymphadenopathy upon evaluation. The excisional biopsy of affected lymph nodes revealed herpes simplex virus lymphadenitis confirmed by immunohistochemical staining. Flow cytometry showed no progression to diffuse large B-cell lymphoma. This case highlights the importance of considering a broad spectrum of differential diagnoses when assessing lymphadenopathy in immunocompromised patients receiving active immunosuppressive therapy.