Nephrotic Syndrome Secondary to Mantle Cell Lymphoma: A Case Report

Abstract: Mantle cell lymphoma (MCL) is a rare type of B cell Non-Hodgkin lymphoma (NHL) with infrequent renal involvement, which can arise from direct lymphomatous infiltration or paraneoplastic glomerulopathy. Minimal change nephrotic syndrome (MCNS) is most commonly described in association with classical Hodgkin lymphoma but remains exceptionally rare in MCL. We report a 65-year-old male who presented with a 12-month history of progressive generalised oedema, nephrotic-range proteinuria and acute kidney injury (AKI) requiring urgent haemodialysis. Laboratory investigations revealed severe hypoalbuminaemia (1.5 g/dL), proteinuria (albumin:creatinine ratio 5020 mg/g), and AKI (creatinine 3.12 mg/dL; eGFR 21 mL/min/1.73 m²). Serological screening for immune-mediated glomerulopathies was negative. Renal biopsy demonstrated concurrent direct MCL infiltration, MCNS and bone marrow biopsy confirmed Stage IV MCL. His condition was complicated by gastrointestinal bleeding, Staphylococcus capitis bacteremia, and transfusion-dependent anemia. Following initiation of R-CHOP immunochemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone), progressive renal recovery was observed; haemodialysis was successfully discontinued after 12 sessions, with creatinine stabilising at 242–253 μmol/L. This case highlights the importance of considering haematologic malignancies in unexplained nephrotic syndrome and demonstrates that dialysis independence may be achievable with combined lymphoma-directed and nephrological supportive care.