Effect of Recipient Age at Liver Transplantation on Prevalence of Post-Transplant Donor-Specific HLA Antibody

Background: Post-transplant donor-specific HLA antibodies (DSA) may have a detrimental effect on long-term outcomes of organ transplantation. The aim of this study was to specifically evaluate the effect of recipient age on the prevalence of DSA over a long-term follow-up after living donor liver transplantation (LDLT). Material/Methods: A retrospective analysis of DSA evaluations was performed in 50 pediatric patients with HLA data available. Patients were divided into 2 groups based on their age at the time of LDLT: younger (Y) group, age <3 years; older (O) group, age >= 3 years. DSA evaluation was performed using Luminex single-antigen bead assays, with a mean fluorescence intensity >= 1000 used as a cut-off for positive results. Results: There were no between-group differences in terms of sex, ABO incompatibility or acute rejection. Only one of our 50 patients tested positive for class I DSA. Significantly more patients tested positive for HLA-DR DSA in group Y (40.6%) than in group O (11.1%; p=0.02). Recipients <3 years of age at the time of LDLT may be at a higher risk of testing positive for class II DSA. Conclusions: These findings can inform the implementation of cost-effective screening of post-transplant DSA in pediatric LDLT recipients.