Modest dose anti-thymocyte globulin administered intraoperatively is safe and effective in kidney transplantations: a retrospective study

BACKGROUND: Anti-thymocyte globulin (ATG) as induction therapy in renal transplantation is facing the dilemma of reducing the incidence of acute rejection (AR) and delayed graft function (DGF) or increasing risks of infection and malignancy. The purpose of this study was to delineate the safety and efficiency of the optimal ATG dosage. METHODS: We retrospectively evaluated 91 deceased donor kidney transplant recipients (KTRs) in our institution between March 2011 and January 2019. The patients were classified into three groups based on induction therapy: (1) Group 1: modest-dose ATG (three mg/kg) intraoperatively (N = 21); (2) Group 2: low-dose ATG (1–1.5 mg/kg) intraoperatively (N = 23); (3) Group 3: basiliximab 20 mg both on day 0 and 4 (N = 47). In Groups 1 and 2, all patients received a daily low-dose program (1–1.5 mg/kg each day) with target dosage of six mg/kg. Induction therapy was combined with standard immunosuppressive regimen consisting of calcineurin inhibitors, mycophenolate/the mammalian target of rapamycin inhibitors and corticosteroids. RESULTS: There was no significant difference in patient characteristics among groups. The outcomes of infection rate, biopsy-proven acute rejection, post-transplant diabetes mellitus, graft survival, and patient survival were similar among groups. Compared to the daily low-dose ATG regimen, the intraoperative modest-dose regimen did not cause more dose interruption and hence was more likely to reach the target ATG dosage. The intraoperative modest-dose regimen also seemed to reduce the rate of DGF. DISCUSSION: In recent years, a trend of using a “lower” dose of ATG has seemed to emerge. Our results suggest intraoperative modest-dose ATG followed by daily low-dose ATG regimen was safe and effective in cadaveric renal transplantations for preventing DGF, AR, and graft loss.