Abstract: FR-OR079

HLA-DQ Mismatching and Kidney Transplant Outcomes: A UNOS/OPTN Analysis

Session Information

Category: Transplantation

  • 1702 Transplantation: Clinical and Translational

Authors

  • Leeaphorn, Napat, Beth Israel Deaconess Medical Center, Brookline, Massachusetts, United States
  • Pena, J. ryan, Beth Israel Deaconess Medical Center, Brookline, Massachusetts, United States
  • Thamcharoen, Natanong, Beth Israel Deaconess Medical Center, Brookline, Massachusetts, United States
  • Khankin, Eliyahu V., Beth Israel Deaconess Medical Center, Brookline, Massachusetts, United States
  • Pavlakis, Martha, Beth Israel Deaconess Medical Center, Brookline, Massachusetts, United States
  • Cardarelli, Francesca, Beth Israel Deaconess Medical Center, Brookline, Massachusetts, United States
Background

Recent evidence suggests that HLA epitope-mismatching at HLA-DQ loci is strongly associated with the development of anti-DQ donor-specific antibodies (DSA) and adverse graft outcomes. However, the clinical significance of broad antigen HLA-DQ mismatching (MM) in predicting graft outcomes is not well examined. Using UNOS/OPTN data, we analyzed the effect of HLA-DQ MM on graft outcomes.

Methods

Patients with primary kidney transplants performed between 2007 and 2015 were included. Patients were classified as having either zero HLA-DQ MM, one or two HLA-DQ MM. Primary outcomes were death-censored graft survival (DCGS), and incidence of acute rejection.

Results

95,664 patients were included in the analysis, with median follow-up time of 3.45 years. Of these, 22,379 (23.39%) and 73,294 (76.61%) received zero and one or two HLA-DQ MM kidneys, respectively. After adjusting for HLA-ABDR, various recipient and donor variables and initial immunosuppression, HLA-DQ MM was associated with an increased risk of graft loss in living donor kidney transplant (LDKT) recipients with an adjusted hazard ratio (HR) of 1.12 (95% CI, 1.01-1.26; p=0.042), but not in deceased donor kidney transplant (DDKT) recipients (HR 1.07, 95% CI, 0.99-1.53; p=0.066). When taking cold ischemic time (CIT) into account, HLA-DQ MM was an independent factor for an increased risk of graft loss in DDKT recipients with CIT ≤ 17 hours (HR 1.15, 95% CI 1.03-1.27; p=0.010), but not in DDKT recipients with CIT > 17 hours (HR 1.00, 95% CI, 0.90-1.11; p=0.971). Compared with recipients who received zero HLA-DQ MM kidneys, those who received one or two HLA-DQ MM kidneys had a higher incidence of acute rejection at 1-year with adjusted odd ratios of 1.12 (95% CI, 1.02-1.22; p=0.012) in DDKT and 1.14 (95% CI, 1.03-1.28; p=0.016) in LDKT, respectively.

Conclusion

HLA-DQ mismatching is a predictor for graft survival and acute rejection independent of mismatching of HLA-ABDR and initial immunosuppression. Cold ischemic times of longer than 17 hours appear to obviate the benefit of zero HLA-DQ MM.