Evaluation of the Prevalence of Acute Rejection in Post-kidney Transplant Patients with Acute Tubular Necrosis in Nemazee Hospital During 2010 - 2016

Abstract

Background: Delayed graft function (DGF), defined as the need for dialysis within the first postoperative week, is a common complication after kidney transplantation and is associated with reduced graft survival. Acute tubular necrosis (ATN) and acute rejection are the main underlying causes; however, distinguishing between them is essential for appropriate management. Objectives: This study aimed to determine the histopathological prevalence of ATN and acute rejection in kidney transplant recipients with DGF and to identify the associated immune and nonimmune risk factors. Methods: In this retrospective observational study, 195 adult kidney transplant recipients with DGF were evaluated at a single center between 2010 and 2016. All patients underwent allograft biopsy. Donor and recipient characteristics, induction immunosuppression, and clinical variables were analyzed. Patients were categorized according to biopsy findings as having isolated ATN, isolated acute rejection, or combined ATN and rejection. Results: Acute tubular necrosis was identified in 155 patients (79.5%), whereas acute rejection was present in 86 patients (44.1%). Concurrent ATN and rejection occurred in 55 patients (28.2%). Isolated ATN and isolated rejection were observed in 100 patients (51.3%) and 31 patients (15.9%), respectively. Biopsy findings were significantly associated with several factors. Donor cause of death differed significantly between the isolated ATN and isolated rejection groups (P = 0.01). Recipient sex distribution also differed significantly among groups: ATN versus rejection (P = 0.03), ATN versus ATN plus rejection (P = 0.01), and rejection versus ATN plus rejection (P = 0.001). In addition, the induction immunosuppressive regimen differed significantly across all pairwise comparisons: ATN versus rejection (P = 0.03), ATN versus ATN plus rejection (P = 0.002), and rejection versus ATN plus rejection (P = 0.009). Conclusions: Acute tubular necrosis is the predominant histopathological finding in kidney transplant recipients with DGF; however, acute rejection, either alone or concomitant with ATN, remains common. These findings underscore the critical role of an early allograft biopsy in guiding targeted therapy and optimizing transplant outcomes.