Bortezomib Maintenance for the Treatment of Monoclonal Gammopathy of Renal Significance.

Monoclonal gammopathy of renal significance (MGRS) defines renal diseases resulting from the nephrotoxic effects of monoclonal proteins secreted from non-malignant clonal B cells or plasma cells, that do not meet criteria for multiple myeloma, Waldenstrom's macroglobulinemia, chronic lymphocytic leukemia, or lymphomas. Renal disease in MGRS can result from monoclonal immunoglobulin deposition to different parts of the kidney and includes a wide spectrum of glomerular, tubulointerstitial and vascular renal diseases. Recognizing MGRS is important because renal outcomes are poor and treatments targeting the underlying clonal disease have been associated with improved renal survival. In this case report, we present a case of a patient with proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) subtype of MGRS who underwent a phased clone directed treatment of induction and extended maintenance therapy to achieve renal response.