Fulminant intravascular lymphoma presenting as fever of unknown origin.

Intravascular large cell lymphoma (IVLL) is a rare neoplasm characterized by the proliferation of malignant lymphoid cells within the lumens of small to medium-sized blood vessels. The central nervous system, skin, and endocrine systems are most commonly involved. IVLL may disseminate to the heart, pancreas, liver, spleen, kidneys, and adrenal glands. We report a 52-year-old patient who was admitted for fever of unknown origin for 3 weeks, jaundice and abnormal liver function tests. Fever, high levels of bilirubin, severe anemia, thrombocytopenia, and a very fulminant course characterized the clinical picture. Although bone marrow involvement is quite rare, the diagnosis of IVLL in this patient was done by bone marrow biopsy. The patient was treated with CHOP protocol and received the first course but the aggressive disease led to the patient's death.