Publication:

Clinical outcomes of plasma exchange in acute and chronic antibody-mediated rejection following kidney transplantation: a prospective observational study

Background Antibody-mediated rejection (ABMR) remains a major cause of renal allograft dysfunction and graft loss after kidney transplantation. Plasma exchange (PE) is widely used for antibody removal; however, its effectiveness in acute and chronic ABMR remains incompletely defined.

Methods This prospective observational study was conducted at the Institute of Kidney Diseases and Research Centre–Institute of Transplantation Sciences (IKDRC-ITS), Ahmedabad, Gujarat, India. The study included 60 kidney transplant recipients with biopsy-proven ABMR treated between September 2017 and November 2019. Patients were classified as acute ABMR (n=30) or chronic ABMR (n=30) according to Banff criteria. All patients received plasma exchange in combination with corticosteroids, intravenous immunoglobulin, and optimization of maintenance immunosuppression. Demographic, clinical, histopathological, immunological, and renal outcomes were assessed at baseline, 6 months, and 5 years.

Result Baseline demographic and laboratory characteristics were comparable between groups (p>0.05). Acute ABMR demonstrated significant improvement in histological activity scores following treatment, including C4d, glomerulitis, peritubular capillaritis, and vasculitis (p≤0.002), whereas chronic ABMR showed no significant histological improvement (p>0.05). At 6 months, acute ABMR was associated with significantly better renal function, lower proteinuria, and lower donor-specific antibody levels than chronic ABMR (all p<0.001). At 5 years, acute ABMR maintained superior renal outcomes with lower serum creatinine, lower proteinuria, lower persistent donor-specific antibody positivity, and higher estimated glomerular filtration rate (p<0.001). Chronic ABMR was associated with more hospitalizations (p<0.001), infection-related admissions (p=0.004), cardiovascular events (p=0.002), mortality (p=0.044), and graft loss requiring maintenance dialysis (p=0.026).

Conclusion Plasma exchange is associated with substantial histological and functional recovery in acute ABMR but provides limited benefit in chronic ABMR. Early diagnosis and intervention may improve long-term allograft survival and clinical outcomes.