Evaluation of screening tests for pre-transplant compatibility testing in live-related kidney transplants: Single-center report from India - A prospective observational study

Introduction: Pre-transplant compatibility testing involves the use of different methodologies (cell-based and solid phase based) for the determination of anti-human-leukocyte antigen (HLA) antibodies. Implementation of these donor-recipient methods in the screening of patients awaiting transplantation increased their chance of successful graft and patient outcomes. Materials and Methods: A total of 1054 patients visiting tertiary care hospitals for pretransplant compatibility testing were screened with cell-based tests; complement-dependent cytotoxicity crossmatch (CDC-XM) and flow cytometric crossmatch (FC-XM). The patients positive for either or both screening tests were suspected to have anti-HLA antibodies. Luminex single-antigen bead (SAB) tests were performed in such patients to determine and identify antibody specificity and establish donor-specific antibody (DSA). Results: The study showed a significantly higher sensitivity of the FCXM (94.6%) method when compared with CDC-XM (35.7%), considering the SAB assay as the gold standard technique. The specificity of CDC-XM (100%) was slightly higher than the FC-XM (76.3%). Combination of FC-XM with CDC-XM (17 cases) was 100% sensitive and specific to identify DSA (s). The graft-survival was 94.77% using the proposed algorithm. Conclusions: The combination of CDC-XM and FC-XM, along with SAB assay, could be used as a screening algorithm as it is a useful technique in identifying the specificities of alloantibodies, assessment of DSAs. Hence, the presented algorithm can become a new standard for the identification of potential recipients awaiting kidney transplantation in India.