Factors affecting sensitization following kidney allograft failure

Management of immunosuppression in a kidney transplant recipient with a failed allograft is complex; continuation carries infectious and metabolic risks, and discontinuation can lead to sensitization.

We evaluated risk factors for sensitization in 89 kidney or simultaneous kidney-pancreas recipients, whose kidney transplant failed after January, 2013 and who were subsequently re-evaluated for kidney transplantation.

Among recipients with pre graft failure cPRA < 50%, calcineurin inhibitor (CNI) continuation (OR .11, P = .003) and steroid continuation (OR .17, P = .04) were associated with significantly lower odds of developing an absolute increase in cPRA of ≥50%. Each additional HLA mismatch was associated with OR of 2.16 (P = .02). CNI use was associated with OR of .09 (P = .001) for increase in cPRA to ≥80% if pre graft failure cPRA was <50%, and OR of .08 (P = .02) for increase in cPRA to ≥98% if pre graft cPRA was <80%. Anti-metabolites were continued more often among recipients who had a <50% increase (P = .006); however, the association was lost on multivariate analyses. Weaning off immunosuppression and higher number of HLA mismatches are associated with greater likelihood of sensitization.

While both CNI and steroid continuation conferred some protection against increase in cPRA, CNI continuation was the only factor protecting against becoming highly sensitized.