Human Pooled Immunoglobulin as Treatment of Active Antibody-Mediated Rejection of Transplanted Kidney

• Antibody-mediated rejection (ABMR) has emerged as the leading cause of renal graft loss.
• The optimal treatment protocol for ABMR remains unknown.
• IVIG improved graft function in renal recipients diagnosed with ABMR.

BackgroundAntibody-mediated rejection (ABMR) has emerged as the leading cause of renal graft loss. The optimal treatment protocol in ABMR remains unknown. This study aimed to assess the efficacy of intravenous immunoglobulin (IVIG) for treatment of ABMR in renal recipients.MethodsThirty-nine ABO-compatible cross-match–negative renal recipients with biopsy-proven ABMR composed the study group. Pulses of methylprednisolone (MP) and appropriate enhancement of net state of immunosuppression were applied in all individuals; 17/39 recipients were administered IVIG (IVIG group); the remaining 22/39 patients, identified to be nonadherent or unsatisfactorily immunosuppressed, were kept on the initial treatment (MP group). Serum creatinine concentration was obtained at each of 10 intended visits, and glomerular filtration rate (GFR) was estimated with the use of the standard Modification of Diet in Renal Disease (MDRD) formula. Generalized linear mixed model was used for statistical analysis.ResultsRenal function (modeled as linear slope of MDRD-based GFR change over time, separately for the pre- and post-intervention periods) improved significantly in IVIG-treated recipients. Pre-intervention slopes were −0.72 and −0.46 mL/min/mo for IVIG and MP groups, respectively (P = NS), whereas post-intervention the slopes changed to −0.03 and −0.47 mL/min/mo (IVIG and MP, respectively; P < .005). Within-group changes of slopes at the time of intervention were 0.69 and −0.01 mL/min/mo in IVIG (P < .01) and MP (P = NS) groups, respectively. The relative slope change (pre- to post-intervention) was 0.7 mL/min/mo in favor of the IVIG group (P < .033). None of the classic immunologic or nonimmunologic graft function predictors influenced GFR during 12 months of follow-up.ConclusionsIVIG improved graft function in renal recipients diagnosed with ABMR.