Luminex Crossmatch for Pre-Transplant Workup of Renal Transplants - 30 Months Experience from Indian Subcontinent

Background: Prior to 2013, most centers in India performed only Complement Dependent Cytotoxicity crossmatch (CDCXM) for detection of donor specific antibodies. Aim: This study was undertaken to evaluate the usefulness of Luminex based crossmatch (LXM) for pretransplant detection of HLA class I and II donor specific IgG antibodies in patients with end stage renal disease. Methods: Luminex Crossmatch was performed on samples from 654 patients, which included 582 first time recipients and 72 retransplants. CDC crossmatch was done for all 654 recipients. Panel Reactive Antibody (PRA) screen was performed for 352 (53.8%) recipients. Low resolution HLA typing was done by reverse Sequence Specific Oligonucleotide probes on Luminex platform. Results: Twenty-five recipients (3.8%) had a positive CDCXM. LXM was positive in 277 samples (39.2%): HLA -class I donor specific antibodies (DSA) were detected in 40 (5.6%), class II DSA in 155 (21.9%) and both classes in 82 (11.5%) samples. High background was present in 70 (9.9%) samples the results of which were confirmed by retesting a fresh sample or by correlation with PRA screen. Conclusions: LXM in combination with PRA screen is useful for detection of clinically relevant HLA IgG donor specific antibodies for pretransplant workup and is a huge improvement on CDCXM.