Sensitization on Hemodialysis After Renal Graft Failure: HLA Incompatibility Still Matters

Patients with renal graft failure can develop human leukocyte antigen (HLA) sensitization when returning to dialysis. There is no consensus on which factors could be associated with an increased risk of this kind of sensitization after graft loss. To try to identify some of these factors, a retrospective observational study was performed in our center. Demographic and transplant-related data were collected: HLA mismatches, changes in calculated panel reactive antibody percentage over time, the immunosuppression withdrawal schedule during the first year on hemodialysis (HD), among others. Patients who developed anti-HLA antibodies after 1 year on HD had a greater number of total HLA mismatches (4.15 ± 1.3 vs 3.3 ± 1.1; P = .001), HLA-DR (1.35 ± 0.7 vs 0.7 ± 0.6; P = .001) and HLA-A mismatches (1.70 ± 0.5 vs 1.27 ± 0.7; P = .004) than patients who never developed anti-HLA antibodies. When we only analyzed patients who develop ≥98% calculated panel reactive antibody versus those who persist without anti-HLA antibodies, these differences were more evident (5.2 ± 1.1 MM vs 3.3 ± 1.1 MM; P < .001). The timing of discontinuation of immunosuppression did not influence sensitization. Thus, we have observed that HLA mismatches influence HLA sensitization after graft failure at least during the first year on HD. This study supports the importance of prioritizing HLA matching in patients who may require >1 graft over the years and being aware of the potential importance of HLA mismatches on sensitization on HD.