Evaluation of Panel Reactive Antibodies in Living Donor Liver Transplantation

Acute antibody-mediated rejection (AMR) is a rare but serious complication following liver transplantation that can lead to graft loss. AMR is caused by preformed anti-donor antibodies, ABO incompatibility, or de novo antibodies that develop post-transplantation. In this study, we aimed to evaluate the diagnosis of AMR by comparing the preoperative and postoperative Panel Reactive Antibody (PRA) Class I and Class II results of patients who underwent liver transplantation at our clinic. Seventy consecutive patients and their donors who underwent living donor liver transplantation at our institution between November 2017 and March 2018 were included in this study. Patients were divided into 2 groups: those who developed a more than 3-fold increase in liver function tests (LFTs) in the early postoperative period and those with a normal clinical course. The Mann-Whitney U test was used to compare quantitative data between the groups. The Chi-square test was used for the comparison of qualitative data, and a p -value of less than .05 was considered statistically significant. The nonparametric Wilcoxon Signed Rank test was used to evaluate the difference between preoperative and postoperative PRA I and PRA II levels in patients with elevated enzymes. Postoperative PRA I levels were found to be increased in 9 patients and decreased in 6 patients compared to preoperative levels. No change was observed in the remaining 3 patients. Although this may appear clinically significant, no statistically significant difference was found between postoperative and preoperative PRA I levels ( p = .363). Similarly, postoperative PRA II levels were decreased in 9 patients, increased in 5, and unchanged in 4 when compared to preoperative PRA II levels. This result was also not statistically significant ( p = .721). When an elevation in LFTs occurs in liver transplant recipients, rejection should be considered after excluding vascular and other pathologies. AMR should be included among the possible diagnoses, and PRA testing should be part of the diagnostic workup. However, as observed in our study, changes in PRA levels may not always correlate with a diagnosis of AMR. Therefore, in such cases, a more appropriate approach would be to evaluate PRA results in conjunction with other diagnostic criteria.Key words: Antibody mediated rejection, liver transplantation, panel reactive antibody