'Royal College of Obstetricians & Gynaecologists (RCOG)'
Abstract
HLA matching is not routinely performed for liver transplantation as there is no consistent evidence of benefit, however the impact of HLA mismatching remains uncertain. We explored the effect of class I and II HLA mismatching on graft failure and mortality. 1042 liver transplants performed at a single centre, between 1999 and 2016 with available HLA typing data were included. Median follow up period was 9.38 years (IQR 4.9-14) and 350/1042 (33.6%) transplants resulted in graft loss and 280/1042 (26.9%) in death. Graft loss and mortality were not associated with the overall number of mismatches at HLA-A, -B, -C, -DR and -DQ loci. However, graft failure and mortality were both increased in the presence of one (p = 0.004 and p = 0.01) and two (p = 0.01 and p = 0.04) HLA-A mismatches. Elevated hazard ratios for graft failure and death were observed with HLA-A mismatches in univariate and multivariate Cox proportional hazard models. Excess graft loss with HLA-A mismatch (138/940 (14.7%) of mismatched compared to 6/102 (5.9%) matched transplants) occurred within the first-year following transplantation (OR 2.75, p = 0.02). Strikingly, all grafts lost due to hepatic artery thrombosis were in HLA-A mismatched transplants (31/940 vs. 0/102), as were those lost due to sepsis (35/940 vs. 0/102). In conclusion, HLA-A mismatching was associated with increased graft loss and mortality. The poorer outcome for The HLA mismatched group was due to hepatic artery thrombosis and sepsis and these complications occurred exclusively with HLA-A mismatched transplants. This suggests that HLA-A mismatching is important for post-transplant outcomes and knowledge of HLA-A status may enable enhanced surveillance and interventions to reduce risk of complications or stratified HLA-A matching in high-risk recipients