ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005


The Latest on Twitter

Kidney Week

Abstract: SA-PO114

A Case of Focal Immune-Complex Membranoproliferative Glomerulonephritis (MPGN) in Low-Risk Chronic Lymphocytic Leukemia

Session Information

Category: Onconephrology

  • 1600 Onconephrology


  • Tan, Akira Francis Henghui, Singapore General Hospital, Singapore, Singapore
  • Ong, Shin Yeu, Singapore General Hospital, Singapore, Singapore
  • Loh, Alwin Hwai Liang, Singapore General Hospital, Singapore, Singapore
  • Choo Chon Jun, Jason, Singapore General Hospital, Singapore, Singapore
  • Tan, Hui Zhuan, Singapore General Hospital, Singapore, Singapore

A broad spectrum of kidney diseases is associated with chronic lymphocytic leukemia (CLL). Optimal treatment of low-risk CLL with renal involvement (CLL-R) is unknown.

Case Description

A 48 year-old Chinese man with low-risk CLL presented with new-onset microhematuria and subnephrotic range proteinuria (uPCR 1.88g/g) for evaluation. Peak serum creatinine (sCr) was 115µmol/L (baseline 81µmol/L). Investigations were notable for low C3 (0.88g/L), C4 (<0.06g/L) and IgG-λ monoclonal gammopathy (2g/L). Autoimmune markers, virologies, and serum cryoglobulins were negative.

Kidney biopsy showed focal membranoproliferative (MPGN) pattern of injury. No TMA changes were seen. Immunofluorescence showed C3-dominant glomerular and mesangial staining (2+), and segmental IgM mesangial staining (1+). Segmental C4d staining was observed. No deposits were seen on electron microscopy (EM). Pronase digestion was not performed. Findings were most consistent with CLL-related immune-complex MPGN.

Venetoclax and Obinutuzumab (Ven-Obi) was commenced. Thrombocytopenia developed 2 days after the first obinutuzumab infusion, leading to gross hematuria and acute kidney injury (AKI) (sCr 161µmol/L). Tumour lysis syndrome was excluded. AKI resolved with conservative management. Interestingly, normalization of complements and proteinuria reduction (uPCR 0.38g/g) were observed within 2 weeks of treatment. Treatment is ongoing but remain uncomplicated.


We report a case of focal MPGN with C3 dominance in a patient with low-risk CLL. Lack of antigen retrieval techniques precluded the search for masked deposits. Positive C4d staining, together with low C3 and C4, suggested an immune-complex, instead of an alternative pathway mediated process. The absence of deposits on EM was likely due to early focal disease.

Studies suggest that clone-directed therapies improve renal outcomes in dysproteinemic-related kidney disease, but the optimal regimen and timing of treatment in early/mild CLL-R is unknown. We demonstrated early renal response to Ven-Obi in our patient. No tumor lysis syndrome was observed during treatment, although thrombocytopenia, a rare adverse effect of Obinutuzumab, did occur together with AKI, the latter possibly due to tubular obstruction by red blood cells casts. Longer follow-up is needed to determine treatment efficacy of Ven-Obi in CLL-R.