Background: Delayed graft function (DGF) has significant impact on the short term and long term allograft outcomes after kidney transplantation. However, the impact of DGF on highly sensitized patients in deceased donor kidney transplantation has not been investigated yet.
Methods: We analyzed 655 deceased donor kidney transplantation recipients underwent a panel reactive antibody (PRA) test from October 2005 to December 2018 at Seoul St. Mary’s Hospital and Dongsan Hospital. DGF was defined by the need for dialysis within 2 weeks after kidney transplantation. Highly sensitized patients were defined as PRA greater than 50%. We divided them into four groups based on the development of DGF and sensitization. Out of 534 patients with PRA below 50%, 437 patients were low PRA without DGF group and 97 patients were low PRA with DGF group. A total of 121 patients were highly sensitized patients, 96 patients of which were high PRA without DGF group, and the rest 25 patients were high PRA with DGF group. The primary outcome was the death-censored graft loss rate and the secondary outcomes were biopsy proven acute rejection (BPAR), change of allograft function and patient mortality.
Results: In the Kaplan-Meier analysis, death-censored graft loss rate tended to be higher when DGF developed but was not statistically significant. In the highly sensitized group, the cox regression model adjusted by three factors, old age, DM, and prior KT, showed that the death-censored graft loss rate was statistically higher when DGF developed (P = 0.027). And the Hazard ratio was 4.832 (1.197-19.496). The development of BPAR was 14.6% (low PRA without DGF), 20.6% (low PRA with DGF), 21.9% (high PRA without DGF), and 32.0% (high PRA with DGF), respectively. The development of BPAR tended to be higher in the DGF developed group depending on the degree of sensitization. The change of allograft function was statistically different until 1 month after kidney transplantation based on the development of DGF, regardless of the degree of sensitization. Patient mortality did not show statistical difference among the four groups.
Conclusion: The development of DGF in highly sensitized patients may be correlated with a higher death-censored graft loss rate, BPAR, and lower allograft function. However, patient mortality may not be different according to the development of DGF or the degree of sensitization. The synergistic effect of the degree of sensitization and the development of DGF on the allograft outcome is unclear.