WCN26-2682 Intravascular Large B-cell Lymphoma Diagnosed by Renal Biopsy Presenting with Nephrotic Syndrome

Intravascular large B-cell lymphoma (IVLBCL) is a rare, aggressive subtype of extranodal diffuse large B-cell lymphoma characterized by selective proliferation of neoplastic lymphoid cells within small vessels. Its features are heterogeneous and nonspecific, often including fever of unknown origin (FUO) and organ dysfunction, leading to delayed diagnosis. We report a case of IVLBCL diagnosed by renal biopsy in a patient presenting with nephrotic syndrome and unexplained fever.