Abstract: SA-PO199
The Clinico-Pathologic Characteristics of Patients with Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposits
Session Information
- Onconephrology: Immunological Cross-Talk
November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1700 Onconephrology
Authors
- Gudura, Tariku T., Cleveland Clinic, Cleveland, Ohio, United States
- Sawaf, Hanny, Cleveland Clinic, Cleveland, Ohio, United States
- Herlitz, Leal C., Cleveland Clinic, Cleveland, Ohio, United States
- Mehdi, Ali, Cleveland Clinic, Cleveland, Ohio, United States
- Gebreselassie, Surafel K., Cleveland Clinic Florida, Weston, Florida, United States
- Bobart, Shane A., Cleveland Clinic Florida, Weston, Florida, United States
Background
Proliferative glomerulonephritis with monoclonal immunoglobin (Ig) deposits (PGNMID) is a rare form of monoclonal gammopathy of renal significance (MGRS). However, the Monoclonal (M) protein and hematologic clone is found in less than half of the cases.
Methods
We identified all patients with PGNMID from the Cleveland Clinic Kidney Biopsy Epidemiology Project from January 2015 to March 2023. Retrospective chart review was performed to obtain demographic and clinical characteristics.
Results
From 34 patients with PGNMID, 16 patients were excluded due to insufficient data. Of the 18 remaining patients, 67% were male and 78% of patients self-reported as white. The median age was 60 years, with 22% of patients < 50 years. Clinically, features at kidney biopsy were: hypertension (78%), acute kidney injury (72%), hematuria (78%), nephrotic syndrome (22%), and hypocomplementemia (23%). M protein was identified in 33% with an underlying clone identified in only 17% (3/18) of cases (MM, CLL and B cell lymphoma). Mean serum creatinine and proteinuria at biopsy were 3.2mg/dl (0.64 - 9.0) and 4.3 gm/dl (0 - 14.0gm) respectively.
Regarding pathology, endocapillary hypercellularity (55%), pure mesangial (28%) and MPGN (16%) patterns were most common. The majority of patients (>65%) had mild chronicity and 1 case had crescents. IgG/Kappa was the predominant finding (83%), one patient had IgM/Kappa. Of 13 patients with IgG subclass staining, 77% had IgG3 and one case each of IgG1, IgG2 and IgG4. CyBorD and CyBord-Daratumumab were the most common chemotherapy regimens used, each accounting 35% followed by Rituximab in 12% of cases.
Regarding outcomes, 18 patients had follow up data, with 8 (44%) progressing to ESKD post biopsy with mean duration of 7.8 months (0 - 13) and 44% had either complete (< 0.5 g) or partial remission (proteinuria reduction > 50% with stable eGFR) during follow up. No clinico-pathologic variables were predictive of response on univariate and multivariable analysis.
Conclusion
Our study adds to growing evidence of low clonal detection rate among patients with PGNMID and high rate of disease progression despite treatment. More studies are needed to better understand the true nature of this disease to hopefully guide therapeutic interventions.