Objective: Acute rejection infrequently occurs among immunologically low-risk recipients within the first few weeks after transplantation, and the role of induction treatment in the frequency of acute rejection and graft loss remains debatable.
Materials and Methods: This retrospective study analyzed 208 kidney transplant recipients with low immunological risk, defined by living donor transplantation, no prior transplantation history, absence of preformed anti-HLA antibodies, and a negative lymphocyte crossmatch prior to transplantation. Demographic data, immunologic characteristics, and graft functions were analyzed concerning early acute rejection history.
Results: Fifteen patients (7.2%) experienced acute rejection within two weeks post-transplantation. No correlation was found between the number of HLA mismatches and induction treatment with early acute rejection. The cumulative incidences of acute rejection in the no-induction and basiliximab groups were comparable at 7.8% and 6.4%, respectively. Donor age was markedly higher, and the tacrolimus trough level on the seventh day post-transplantation was significantly lower in the early acute rejection group; however, the significance was lost after adjustment. The incidence of graft loss was higher in the early acute rejection cohort than in the no-rejection cohort (33.3% vs. 3.1%, p<0.001). Early acute rejection was the only independent risk factor for graft failure (HR 10.286, CI 1.944–54.409, p=0.006).
Conclusion: Acute rejection within two weeks post-transplantation has been associated with suboptimal graft function in recipients with low immunological risk. Basiliximab does not provide additional advantages in preventing early acute rejection in patients with a low immunological risk on tacrolimus-based immunosuppression.