Renal Involvement in Chronic Graft-Versus-Host Disease.

Area of Science:

• Nephrology
• Hematology
• Immunology

Background:

• Graft versus host disease (GvHD) is a common complication after allogeneic hematopoietic stem cell transplantation (HSCT).
• While typical GvHD targets skin, eyes, mouth, and liver, kidney involvement is increasingly recognized but poorly characterized.
• Limited data exist on GvHD-associated kidney disease, often from small retrospective studies.

Purpose of the Study:

• To investigate the clinical characteristics, diagnosis, and outcomes of kidney involvement in HSCT recipients.
• To identify the specific renal pathology associated with GvHD-induced nephrotic syndrome.
• To evaluate the efficacy of immunosuppressive therapy in managing renal GvHD.

Main Methods:

• Retrospective analysis of 1441 HSCT patients.
• Identification of patients with nephrotic syndrome and renal biopsy confirmation of membranous nephropathy (MN).
• Review of clinical data, including proteinuria, time to diagnosis, renal vein thrombosis, pathology, and treatment response.

Main Results:

• Twelve patients (0.8%) developed nephrotic syndrome with biopsy-proven MN post-HSCT, with no prior renal disease.
• Median proteinuria was 6.6 g/24h; diagnosis occurred 1.8 years post-HSCT and 407 days after GvHD diagnosis.
• Immunosuppressive therapy led to complete or partial response in 11 of 12 patients; none developed irreversible renal impairment.

Conclusions:

• Kidney involvement, presenting as nephrotic syndrome with membranous nephropathy, is a rare but significant complication of HSCT.
• Renal biopsy is essential for diagnosing GvHD-induced kidney disease in the absence of specific biomarkers.
• Early immunosuppressive treatment is effective in managing renal GvHD and preventing irreversible kidney damage.