C3 glomerulonephritis; a rare complication of CLL

Kidney disease develops in chronic lymphocytic leukemia (CLL) patients via multiple mechanisms including infiltration, obstruction, tumor lysis syndrome, and glomerular disease. We present a rare case of C3 glomerulonephritis (C3GN) associated with pulmonary renal syndrome that we believe was an autoimmune manifestation of CLL. A 76-year-old male with a 15-year history of SLL/CLL, DVT, HTN, DM and Stage 3 CKD developed SOB and dry cough. At ED presentation he was in respiratory distress with BIPAP-resistant hypoxia requiring intubation. Labs included Cr 7.1 mg/dL, K 5.7 mEq/L and uric acid 12.2 mg/dL CXR showed vascular congestion. Prior to developing anuria urine sediment showed RBC casts. Bronchoscopy DAH, consistent with a pulmonary renal syndrome. Patient was started on plasmapheresis, high-dose steroids and CRRT. Autoimmune workup including ANA, anti-GBM and ANCA was negative. Kidney biopsy showed diffuse proliferative and sclerosing glomerulonephritis with lymphocytic infiltrates consistent with involvement by patient\u27s known CD5+, CD23+ B-cell lymphoproliferative disorder. IF showed diffuse C3 staining. Steroids and plasmapheresis were continued. Renal function improved and dialysis discontinued, with Cr at last follow up 1.9. Chemotherapy for CLL has been ordered. We present a case of C3GN and DAH secondary to CLL autoimmune etiology, a rare complication of CLL which usually affects the kidney by infiltration and by toxicity of the CLL treatment. Due to the rarity of the disease, there is no standard of care treatment but this patient initially responded well to steroids and plasmapheresis. Recent case reports suggest improved outcomes of CLL-associated C3GN when CLL is treated. CLL is a rare cause of C3GN. A high suspicion of the disease and early intervention with immunosuppression is the key in treating such condition. Chemotherapy for CLL is expected to improve the patient\u27s long-term renal outcome