The predictors and risk factors of two-year rejection in renal transplant patients: A multicenter case-control study

Am J Nephrol. 2024 Apr 26. doi: 10.1159/000538963. Online ahead of print.

Abstract

Introduction: Kidney transplantation is a definitive treatment for end-stage renal disease. It is associated with improved life expectancy and quality of life. One of the most common complications following kidney transplantation is graft rejection. To our knowledge, no previous study has identified rejection risk factors in kidney transplant recipients in Saudi Arabia. Therefore, the purpose of this study was to determine the specific risk factors of graft rejection.

Methods: A multicenter case-control study was conducted at four transplant centers in Saudi Arabia. All adult patients who underwent a renal transplant in the period between 01/01/2015 and 31/12/2021 were screened for eligibility. Included patients were categorized into two groups (cases and control) based on the occurrence of biopsy-proven rejection within two years. The primary outcome was to determine the risk factors for rejection within the first two years of transplant. Exact matching was utilized using a 1:4 ratio based on patients' age, gender, and transplant year.

Results: Out of 1320 screened renal transplant recipients, 816 patients were included. The overall prevalence of two-year rejection was 13.9%. In bivariate analysis, deceased donor status, the presence Donor Specific Antibody (DSA), intraoperative hypotension, serum Chloride levels, Pseudomonas aeruginosa, Candida, and any Infection within two years were linked with increased risk of two-year rejection. However, in the logistic regression analysis, DSA was identified as a significant risk for two-year rejection (Adjusted OR 2.68; 95% CI, 1.10, 6.49, p = 0.03). While, the presence of Panel-reactive antibody (PRA) and higher serum chloride levels one week prior to transplant was associated with lower odds of rejection (Adjusted OR 0.12; 95% CI, 0.03, 0.53, p = 0.005 and Adjusted OR 0.93; 95% CI, 0.86, 0.98, p = 0.02, respectively). Furthermore, blood infection, infected with Pseudomonas aeruginosa or BK virus within two years of transplant was associated with higher odds of two-year rejection (Adjusted OR 3.10; 95% CI, 1.48, 6.48, p = 0.003, Adjusted OR 3.23; 95% CI, 0.87, 11.97, p = 0.08 and Adjusted OR 2.76; 95% CI, 0.89, 8.48, p = 0.07, respectively).

Conclusion: Our findings emphasize the need for appropriate prevention and management of infections following kidney transplantation to avoid more serious problems, such as rejection, which could significantly raise the likelihood of allograft failure and probably death. Further studies with larger sample size are needed to investigate the impact of serum chloride levels prior to transplant and intraoperative hypotension on the risk of rejection.