Primary splenic diffuse large B-cell lymphoma masquerading as systemic lupus erythematosus: a case report

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma, while primary splenic DLBCL is extremely rare. The article describes a case of an elderly patient with recurrent fever, hyperinflammatory state, and decreased blood cell counts who tested positive for autoimmune antibodies and lupus anticoagulant, strongly suggesting systemic lupus erythematosus. However, the patient did not respond to adequate doses of corticosteroids. Bone marrow and peripheral blood flow cytometry examination revealed a small population of aberrant B cells, and positron emission tomography-computed tomography showed mild splenomegaly with diffuse increased fluorodeoxyglucose uptake. The definitive diagnosis of primary splenic DLBCL was confirmed only after splenectomy. Unfortunately, the patient died of sudden cardiac death shortly after diagnosis.