Abstract: PO1464
Clinical and Histological Features of Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposits: A Single-Center Retrospective Study from China
Session Information
- Glomerular Diseases: Immunology and Inflammation in IgANP, C3GP, TMA, and Nephrotic Diseases
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Wang, Yifeng, Huashan Hospital Fudan University, Shanghai, Shanghai, China
- Zhu, Xiaoye, Huashan Hospital Fudan University, Shanghai, Shanghai, China
- Liu, Shaojun, Huashan Hospital Fudan University, Shanghai, Shanghai, China
- Xue, Jun, Huashan Hospital Fudan University, Shanghai, Shanghai, China
- Hao, Chuan-Ming, Huashan Hospital Fudan University, Shanghai, Shanghai, China
Background
PGNIMID is a new entity of monoclonal gammopathy affecting the kidney characterized by intact monoclonal immunoglobulins (mIg) deposits that result in membranoproliferative pattern of glomerular injury. In this study, clinical and histological of PGNMID cases were evaluated.
Methods
A total of 23 patients with biopsy-confirmed PGNMID in native kidney diagnosed between December 2015 to April 2021 were enrolled in this study. Clinical, histological, hematologic, and follow-up data were abstracted from the medical record.
Results
Of 23 cases, majority were male (65.2%), and the mean age was 49.5 years with 8 cases (34.8%) under 40 years old.At the time of biopsy,19 cases had proteinuria with a mean 24h urine protein of 3.99g (0.28 to 8.96), 11 of 22 cases had nephrotic syndrome, and 18 of 22 cases had hematuria. The mean serum creatinine was 1.52mg/dL (0.6 to 7.8), 15 cases (65.2%) had eGFR<90 mL/min (CKD-EPI), and 4 cases had eGFR <60 mL/min.Eleven of 23 cases (47.8%) showed MPGN, 6 cases showed EPGN, 2 cases showed MesPGN, and 2 cases showed MN. By IF, 21 cases (91.3%) showed mIgG deposits (12 IgG3κ, 5 IgG1κ, 1 IgG1λ, 1 IgG3λ, and 2 IgGκ without determined subclass) and 2 cases (8.7%) showed mIgAλ deposits. All cases showed C3 co-deposits, and 6 of 18 cases (33.3%) had a low serum C3 level. EM revealed unorganized and granular deposits in the mesangial area (17 of 17), subendothelial area (15 of 17), and subepithelial area (12 of 17). Three of 4 cases whose eGFR<60 mL/min showed EPGN. SIFE showed mIg that matched the renal deposits in 2 of 13 cases (15.38%). After mean follow up of 3 months in 3 cases, 1 patient treated with bortezomib+ CTX+DXM and another patient treated with rituximab both achieved partial renal remission. But the third patient treated with rituximab had a persistent renal dysfunction.Of note, previous or concurrent infections by fungi, HIV, HBV, HPV or other undetermined pathogen, were observed in 5 cases (21.7%). We also found 1 patient with autoimmunity and another with malignancy.
Conclusion
Compared with previous reports, our PGNMID cases showed similar clinical and histological features. EPGN pattern seems to be associated with more severe renal function damage. Previous or concurrent infections, autoimmunity and malignancy were observed in 21.7% of cases.