Impact of active antibody-mediated rejection treatment on donor-specific antibodies in pediatric kidney transplant recipients.

Abstract

AMR is a major cause of graft loss after kidney transplantation. We evaluated a retrospective cohort of 13 pediatric kidney transplant patients diagnosed with active AMR. All 13 patients were treated with plasmapheresis (PP), IVIg, and rituximab. Anti-HLA DSAs were measured at the time of transplantation, AMR diagnosis, 30days post-rejection treatment, 90days post-rejection treatment, and 24±12months post-AMR. A total of 68 DSAs were identified from 13 patients at the time of active AMR diagnosis. The primary objective of this study was to differentiate treatment response rates between class I and class II anti-HLA DSA post-AMR treatment. Overall, DSAs were significantly reduced at 30days, and the reduction was sustained at 90days post-treatment, even for class II anti-HLA and strongly positive DSAs. A significant difference between class I and class II anti-HLA DSA was observed at 30days; however, between class significance was lost at 90-day follow-up due to continued class II anti-HLA DSA treatment response. Low DSA strength was predictive of treatment response. eGFR demonstrated significant improvement 90days after AMR diagnosis compared to the initial value at the time of AMR, and the effect was sustained for 12months. These results suggest that the AMR treatment is effective in pediatric kidney transplant recipients with an early diagnosis of active AMR across both class I and class II anti-HLA DSAs.