Impact of Low-Level Donor-Specific Anti-HLA Antibody on Posttransplant Clinical Outcomes in Kidney Transplant Recipients

Abstract

Background:The clinical significance of low-level donor-specific anti-HLA antibody (low-DSA) remains controversial. We investigated the impact of low-DSA on posttransplant clinical outcomes in kidney transplant (KT) recipients.Methods: We retrospectively reviewed 1,027 KT recipients, namely, 629 living donor KT (LDKT) recipients and 398 deceased donor KT (DDKT) recipients, in Seoul St. Mary's Hospital (Seoul, Korea) between 2010 and 2018. Low-DSA was defined as a positive anti-HLA-DSA result in the Luminex single antigen assay (LABScreen single antigen HLA class I -combi and class II -group 1 kits; One Lambda, Canoga Park, CA, USA) but a negative result in a crossmatch test. We compared the incidence of biopsy-proven allograft rejection (BPAR), changes in allograft function, allograft survival, patient survival, and posttransplant infections between subgroups according to pretransplant low-DSA. Results:The incidence of overall BPAR and T cell-mediated rejection did not differ between the subgroups. However, antibody-mediated rejection (ABMR) developed more frequently in patients with low-DSA than in those without low-DSA in the total cohort and the LDKT and DDKT subgroups. In multivariate analysis, low-DSA was identified as a risk factor for ABMR development. Its impact was more pronounced in DDKT (odds ratio [OR]: 9.60, 95% confidence interval [CI]: 1.79-51.56) than in LDKT (OR: 3.76, 95% CI: 0.99-14.26) recipients. There were no significant differences in other outcomes according to pretransplant low-DSA.Conclusions: Pretransplant low-DSA has a significant impact on the development of ABMR, and more so in DDKT recipients than in LDKT recipients, but not on long-term outcomes.

Impact of Low-level Donor-specific Antibody Determined With a Positive Luminex and Negative Flow Cytometric Crossmatch on Kidney Transplantation Outcomes

“…Given its well-known association with better allograft outcomes despite the presence of DSAs, several institutions consider desensitization treatment. Lee, et al [12] showed that patients who received desensitization treatment to achieve low-level DSA (PLNF) before transplantation did not have a notable increase in the risk of graft failure, and there was also no increased risk of post-transplant infection.…”

“…In this issue of Annals of Laboratory Medicine , Lee, et al . [ 12 ] reported the results of an analysis of 1,090 kidney transplantation patients (629 living and 398 deceased donors), wherein 178 patients (127 living and 51 deceased donors) had undergone desensitization before transplantation. In these 178 patients, sera collected after desensitization prior to transplantation were used for DSA analysis using the Luminex assay and flow cytometric crossmatch approach.…”

“…In this study by Lee, et al . [ 12 ], a higher proportion of low-level DSA (PLNF) patients with living donors received desensitization treatment, including not only rituximab but also plasmapheresis/intravenous immunoglobulin, which might have contributed to a better allograft outcome. Desensitization treatment did not increase the risk of post-transplant infection in their study.…”

“…Lee, et al . [ 12 ] showed that patients who received desensitization treatment to achieve low-level DSA (PLNF) before transplantation did not have a notable increase in the risk of graft failure, and there was also no increased risk of post-transplant infection.…”

“…Despite the main limitation of the study by Lee, et al . [ 12 ] as a single-institution study, this work has the advantage of accurately determining the effect of low-level DSA (PLNF) on kidney transplantation outcomes using a unified immunosuppressive treatment protocol. The authors did not analyze the peak MFI before desensitization, which might have affected the study results.…”