Kidney Week

Abstract: SA-PO0824

Clinicopathological Features and Kidney Outcomes of Biopsy-Proven Monoclonal Gammopathy-Associated Kidney Disease: A Single-Center Case Series

Session Information

• Glomerular Diseases: Management, Evolving Strategies, and Practice-Changing Advances
  October 24, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Arabi, Ziad, King Abdulaziz Medical City in Riyadh, Riyadh, Riyadh Province, Saudi Arabia

Ziad Arabi, MD

• Khormi, Abdullah Hassan, King Abdulaziz Medical City in Riyadh, Riyadh, Riyadh Province, Saudi Arabia

Abdullah Hassan Khormi, MBBS

• Alreshidi, Ahmed Abdullah, King Abdulaziz Medical City in Riyadh, Riyadh, Riyadh Province, Saudi Arabia

Ahmed Abdullah Alreshidi, MBBS

• Alabdulsalam, Abdulrahman K., King Abdulaziz Medical City in Riyadh, Riyadh, Riyadh Province, Saudi Arabia

Abdulrahman K. Alabdulsalam, MBBS

• Aloudah, Nourah Mohamed, King Abdulaziz Medical City in Riyadh, Riyadh, Riyadh Province, Saudi Arabia

Nourah Mohamed Aloudah, MD

• Alsadhan, Abdulmajeed Abdullah, King Abdulaziz Medical City in Riyadh, Riyadh, Riyadh Province, Saudi Arabia

Abdulmajeed Abdullah Alsadhan, MD

Background

Monoclonal gammopathy-associated kidney disease represents a heterogeneous group of renal lesions caused by monoclonal immunoglobulin deposition and tubular toxicity. We describe the renal presentation, histopathological findings, and renal outcomes of biopsy-proven cases at our center, representing one of the largest reported series from the region.

Methods

We retrospectively reviewed 1,127 native kidney biopsies performed between 2015 and 2026. Nine patients with biopsy-confirmed monoclonal gammopathy-associated kidney disease were identified. Clinical, laboratory, histopathological, and renal outcome data were analyzed.

Results

Nine patients were identified (0.8% of native kidney biopsies). Median age was 69 years (range 52–85), and 7/9 (77.8%) were male. Renal manifestations included proteinuria in 9 patients (100%), microscopic hematuria in 8 (88.9%), and acute kidney injury in 7 (77.8%). Median presenting serum creatinine was 457 µmol/L (range 144–2770). Four patients (44.4%) required hemodialysis at presentation and remained dialysis-dependent, while 4 others developed persistent CKD.
Multiple myeloma was identified in 7 patients (77.8%). IgG kappa monoclonal gammopathy was the most common subtype (44.4%), while kappa light-chain restriction was identified in 6 patients (66.7%).
Histopathological findings were heterogeneous. Myeloma cast nephropathy/light-chain cast nephropathy was identified in 4 patients (44.4%), monoclonal deposition disease-related lesions in 2 (22.2%), AL amyloidosis in 1 (11.1%), PGNMID in 1 (11.1%), and proximal tubulopathy with crystals in 1 (11.1%). Moderate-to-severe interstitial fibrosis/tubular atrophy was present in 8/9 biopsies (88.9%).
Median follow-up duration was 4 years (range 3 months–9 years). Four patients (44.4%) died during follow-up.

Conclusion

Monoclonal gammopathy-associated kidney disease is an uncommon but clinically significant cause of severe renal injury with diverse histopathological manifestations and frequently poor renal and patient prognosis. High presenting creatinine, chronic histologic injury, and dialysis dependence at presentation were associated with adverse outcomes. Kidney biopsy remains essential for diagnosis and guiding management.