Abstract: SA-PO282

Renal Outcomes in Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposits

Session Information

Category: Glomerular

  • 1005 Clinical Glomerular Disorders

Authors

  • Gumber, Ramnika I., University of Pennsylvania, Philadelphia, Pennsylvania, United States
  • Cohen, Jordana B., University of Pennsylvania, Philadelphia, Pennsylvania, United States
  • Palmer, Matthew, University of Pennsylvania, Philadelphia, Pennsylvania, United States
  • Dember, Laura M., University of Pennsylvania, Philadelphia, Pennsylvania, United States
  • Weiss, Brendan M., University of Pennsylvania, Philadelphia, Pennsylvania, United States
  • Hogan, Jonathan J., University of Pennsylvania, Philadelphia, Pennsylvania, United States
Background

The natural history and response to therapy of proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) is poorly characterized.

Methods

We retrospectively analyzed renal responses of 20 patients with PGNMID evaluated at our center from 2011 though 2016. Patients were stratified by treatment approach: targeted to detected clonal cell type or non-targeted. Renal response was defined as: 1. complete response (CR) if proteinuria decreased to <0.5 grams (per 24h urine collection or urine protein:creatinine ratio<0.5) with return to baseline of serum creatinine (SCr) 2. partial response (PR) if there was ≥50% decrease in proteinuria (and at least <3 grams) with stabilization of SCr.

Results

Median eGFR at presentation was 37 (interquartile range (IQR) 22-56) ml/min/1.73m2, median proteinuria was 3.7 (IQR 2.5-8.1) grams. A paraprotein was detected in serum or urine in 8 patients and an underlying clone was detected in 7 patients (B cell n=2, plasma cell n=3, lymphoplasmacytic cell n=2); 5 of these patients received clone-directed therapy. All patients with clone-directed therapy had a renal response (CR in 60%); 54% of patients not receiving clone directed therapy had a renal response (CR in 27%). All patients receiving bortezomib-based therapy (n=4) had renal response (CR in 75%); 67% of patients not receiving bortezomib-based therapy (n=12) had renal response (CR in 25%). Among those who responded, median time to any renal response was 98 days in bortezomib-treated patients vs. 190 days in non-bortezomib-treated patients.

Conclusion

All patients with PGNMID who received clone-directed therapy had a renal response. Future studies should explore more sensitive methods for detecting an underlying pathogenic clone to direct treatment. Bortezomib appears promising for these conditions and should be explored further.

Renal response stratified by treatment approach
 Clone-Directed Therapy
(N=5)
Non-Clone Directed Therapy
(N=11)
No Therapy
(N=4)
Complete Response3 (60%)3 (27%)0 (0%)
Partial Response2 (40%)3 (27%)0 (0%)
No Response0 (0%)5 (45%)4 (100%)