HLA-DQ matching in cadaveric renal transplantation

The impact of matching for the human leukocyte antigen (HLA)-DQ phenotype in cadaveric renal transplantation is unclear. We analyzed the effect of matching serologically defined HLA-DQ phenotypes on renal allograft survival in 12,050 first cadaveric renal transplants (recipients were 63.5% white and 36.5% African-American). Recipients were entered into the South-Eastern Organ Procurement Foundation (SEOPF) database between 1 October 1987 and 6 June 1995. A series of life table analyses were done to test the equality of survival curves for HLA-DQ match, both alone and accommodating for differences in recipient race and HLA-DR match. Cox regression models were then performed to detect differences in allograft survival based upon HLA-DQ match. Initial adjustments were done by recipient race. Subsequent adjustments were done by recipient and donor race, age and sex, cold ischemia time (CIT), body mass index (BMI), cyclosporine A (CyA) use, peak panel reactive antibody (PRA) titer, year of transplant, presence of diabetes mellitus (DM), and degree of HLA-A,B and HLA-DR match as covariates. The effect of varying degrees of HLA-DQ match on graft survival were similar between the two races (p = 0.87). In all recipients, an 8.3% reduction in graft failure was observed for each increase in HLA-DQ match using the Cox regression model adjusted only for recipient race (p = 0.004). A non-significant 3.0% reduction in graft failure (p = 0.38) was observed for each level of increasing HLA-DQ match when using the Cox regression model adjusted for recipient and donor race, age and sex, CIT, BMI, CyA use, year of transplant, DM, HLA-A,B and -DR match. In this model, superior HLA-A,B match and HLA-DR match, recipient and donor age, male donor sex, shorter CIT, white race of recipient, lower peak PRA, CyA use, and absence of DM significantly improved graft survival (all < or = 0.004). We conclude that HLA-DQ matching does not significantly affect cadaveric renal allograft survival once adjusted for other known predictors of graft outcome.