Monoclonal gammopathy of renal significance in low‑middle income settings: delayed management leads to end‑stage kidney disease

Abstract

Monoclonal Gammopathy of Renal Significance (MGRS) represents a serious yet underrecognized condition that can cause irreversible kidney damage despite not meeting the diagnostic criteria for hematological malignancy. We report a case of a 38-year-old woman who presented with new-onset nephrotic syndrome, hematuria, and impaired kidney function. Kidney biopsy revealed IgG-dominant monoclonal heavy-chain deposits, with electron microscopy demonstrating electron-dense deposits. A lambda-restricted serum paraprotein was also detected, despite bone marrow plasmacytosis <10-15%. Delayed multidisciplinary nephrologist and hematologist assessment, resulting from by fragmented diagnostic testing, initially incomplete biopsy immunofluorescence examination of the kidney biopsy, and absence of multidisciplinary protocols, precluded early clone-directed therapy. Consequently, the patients progressed to end-stage kidney disease (ESKD) requiring dialysis within months. This missed therapeutic opportunity illustrates the aggressive renal course of MGRS in low- and middle-income settings like Egypt, limitations may increase the risk of disease progression. This case highlights the importance of comprehensive biopsy processing, prompt serum/urine electrophoresis, free light chain measurement, and bone marrow examination, and close collaboration between hematologists and nephrologists to facilitate timely clone-directed therapy and preserve kidney function. MGRS should be routinely considered in patients with unexplained glomerular disease. Standardized diagnostic and management protocols may reduce the risk of progression to ESKD, emphasizing the urgent need for greater global awareness and equitable access to onconephrological care.