Donor-specific antibodies present at the time of kidney transplantation in immunologically unmodified patients increase the risk of acute rejection.

BACKGROUND: Human leukocyte antigens (HLA) class II donor-specific antibodies (DSAs) are associated with microcirculation inflammation, transplant glomerulopathy and ultimately graft loss. There is however no data on allograft outcomes in deceased donor kidney transplant recipients who have not received any desensitization prior to transplantation.

METHODS: We prospectively evaluated the association of HLA DR and DQ DSAs on rejection and short-term graft survival in patients who did not receive desensitization prior to transplantation. On the basis of their cumulative strength of HLA DR and/or DQ DSA, the patients were dichotomized into: 1) median fluorescence intensity (MFI)<1000 and 2) MFI≥1000.

RESULTS: In the two year study period, 50 consecutive patients with HLA DR and/or DQ sensitization were transplanted in our two centers. Post-transplantation, the incidence of acute rejection was significantly greater in the MFI≥1000 group (35%; 8/22) compared to the MFI<1000 group (7%; 2/28) (p<0.001). There were two graft losses, both in the MFI≥1000 group.

CONCLUSION: The strength of DR and/or DQ DSA at the time of renal transplantation influences the risk of rejection in non-desensitized recipients with HLA class II DSA.