Long-term outcome of lung transplantation is predicted by the number of HLA-DR mismatches

Background. The importance of HLA mismatch in determining long-term outcome in lung transplantation remains largely uncertain.Methods. A retrospective analysis of 102 consecutive primary lung transplants was performed to identify risk factors for poor long-term outcome after lung transplantation defined as graft survival and bronchiolitis obliterans syndrome (BOS) stage I and II. Variables included were patient characteristics (age, sex, prior diagnosis), the number of HLA mismatches between donor and recipient, cold ischemic time, cyto-megalovirus serologic concordance, number of acute rejections, and time to first rejection. Variables carrying significance in a univariate analysis were subjected to a proportional hazard regression analysis.Results. In the multivariate analysis, arn increased number of acute rejections correlated positively with decreased graft survival (risk ratio [RR]=1.25; 95% confidence interval [CI], 1.05-1.5; P=0.011), development of BOS stage I (RR=1.36/episode; 95% CI, 1.16-1.58; PConclusions. HLA-DR mismatching appears to be a risk. factor for the development of BOS and graft loss, Improved outcome after lung transplantation might be achieved with prospective matching for HLA-DR. Alternatively, the amount and type of immunosuppressive drugs may be guided by the degree of HLA-DR (mis)matching.