Use of the Monocyte-to-Lymphocyte Ratio to Predict Delayed Graft Function in Patients after Kidney Transplantation

Background: Delayed graft function (DGF) is a significant complication following kidney transplantation, affecting graft survival. The monocyte-to-lymphocyte ratio (MLR) is being explored as a potential predictor of DGF, reflecting inflammatory and immune responses. Evaluating MLR's utility in predicting DGF could improve patient management post-transplantation. Methods: Medical records of patients undergoing kidney transplantation at Police General Hospital from January 1989 to December 2023 were reviewed. DGF was defined as a temporary impairment of kidney function immediately after transplantation, requiring dialysis within the first week post-transplant. Clinical data and laboratory were collected. The optimal cut-off value for MLR was determined using receiver operating characteristic (ROC) curve analysis. Univariate and multivariate logistic regression models were performed to investigate the risk factors associated with DGF. Results: A retrospective cohort study was conducted on 162 kidney transplant patients, of which 58 had DGF, while 104 did not. Clinical outcomes focused on DGF, with MLR investigated as a potential biomarker. In the receiver-operating characteristic (ROC) curve analysis, MLR, with an optimal cut-off value of 0.255 (AUC of 0.686; 95% CI 0.603, 0.769; P < 0.001), predicted the DGF with a sensitivity of 81.0% and specificity of 55.8%. The multivariate logistic regression analysis confirmed that MLR was an independent factor of DGF (MLR) >0.255 (Adj. OR 3.74 [95% CI 1.55, 9.02], P=0.003). Conclusion: This study suggested that high MLR may associated with DGF. The MLR is an inexpensive and straightforward indicator to reflect systemic inflammation status to help clinicians improve kidney transplant care.