HLA-DQ Mismatching and Kidney Transplant Outcomes

Area of Science:

• Transplantation immunology
• Organ transplantation outcomes
• HLA genetics

Background:

• HLA-DQ mismatching is linked to anti-DQ donor-specific antibodies and poor graft outcomes.
• The clinical impact of broad HLA-DQ antigen mismatching on graft survival requires further investigation.

Purpose of the Study:

• To examine the association between HLA-DQ mismatching and kidney transplant outcomes.
• To assess the impact of HLA-DQ mismatching on graft survival and acute rejection rates.

Main Methods:

• Analysis of primary kidney transplant data from 2005-2014 (UNOS/OPTN).
• Classification of patients into zero or one/two HLA-DQ mismatches.
• Evaluation of death-censored graft survival and acute rejection incidence.

Main Results:

• HLA-DQ mismatching increased graft loss risk in living donor recipients (HR 1.18) and deceased donor recipients with cold ischemia time ≤17 hours (HR 1.12).
• A higher incidence of acute rejection at 1 year was observed in recipients with one or two HLA-DQ mismatches (aOR 1.13-1.14).
• Specific HLA-DQ mismatches showed varied associations with rejection and graft failure risk.

Conclusions:

• HLA-DQ mismatching negatively impacts graft survival in living donor kidney transplants and short cold ischemia time deceased donor transplants.
• Increased 1-year acute rejection risk is associated with HLA-DQ mismatching in both living and deceased donor kidney transplants.