Angiotropic Large Cell Lymphoma Presenting as Fever of Unknown Origin
To the Editor: Angiotropic lymphoma is an intravascular large cell lymphoma [1].
Although fever is a common manifestation of this disease, it is extremely rare for it to be initially seen as fever of unknown origin (FUO) [2].
A 67-year-old white woman was admitted with a 3-week history of nausea, vomiting, and diarrhea. She was not aware of fever before her admission and denied weight loss or cutaneous lesions. Her physical examination was notable only for a pulse of 107/min and dry mucous membranes. There were no cutaneous lesions, lymphadenopathy, or organomegaly.
Initial laboratory investigations revealed a hemoglobin of 7.1 g/dL, hematocrit of 20.8%, platelet count of 368,000/L, and a white blood cell count of 6,800/L (differential WBC: 70% neutrophils, 13% lymphocytes, and 15% monocytes). While the patient was hospitalized, repeated episodes of fever up to 103Β°F were noted. An extensive workup for FUO, including repeated blood and urine cultures, chest x-ray, duplex scan of the lower extremities, and computed tomography scans of the chest, abdomen, and pelvis, was unrevealing.
During the third week of hospitalization, a serum immunofixation study revealed the presence of a low-level IgG kappa monoclonal protein. Because of this finding, a punch biopsy of clinically normal abdominal skin and subcutaneous tissue was obtained to look for amyloidosis. The biopsy specimen revealed neoplastic cells filling the lumens of multiple small blood vessels in the dermis and subcutaneous tissue. Immunoperoxidase stains using antibodies to CD3, CD20, and CD79a revealed the cells to be CD20+, large neoplastic B cells indicative of angiotropic lymphoma (Fig. 1). Shortly after the skin biopsy was performed, the patient's condition worsened, and she died.