#2300 Validation Study of the 4-Variable Kidney Failure Risk Equation for Prediction of Allograft Loss in a Group of Pediatric Kidney Transplant Recipients

Abstract Background and Aims Emerging evidence suggests that the 4-variable Kidney Failure Risk Equation (KFRE) can be used to predict the risk of graft failure in adult transplant recipients. However, research studies in pediatric patients are lacking. This study aimed to validate the 4-variable KFRE (age, sex, estimated glomerular filtration rate [eGFR], and urine albumin-to-creatinine ratio [uACR]) for prediction of the 2- and 5-year risk of graft failure in a group of pediatric transplant patients. Method A retrospective observational study involving 59 pediatric patients who underwent kidney transplant between January 2007 and December 2017 was conducted. The KFRE risk scores were calculated with data collected at 1-year post-transplantation. The area under the receiver operating characteristic curves (AUC) and calibration plots were used to assess the discrimination and calibration properties of the 4-variable KFRE in predicting the risk of graft failure at 2 and 5 years from the point of the 1-year post-transplantation measurements. Results Among the 59 patients, 41 (69.5%) were male, with median age of 12.8 years (interquartile range 9.2-15.7) at the time of the kidney transplant. Eleven (18.6%) were living donor recipients. Median eFGR at 1-year post-transplantation was 62.0 mL/min/1.73 m2 (50.0-76.5); 1 (1.7%) and 3 (5.1%) patients developed graft failure within 2 and 5 years from the point of the 1-year post-transplantation measurements, respectively. The 4-variable KFRE showed excellent discrimination for the 2-year risk (AUC 0.966, 95% confidence interval [CI] 0.914-1.000) and very good discrimination for the 5-year risk (AUC 0.887, 95% CI 0.732-1.000). Calibration plots however showed imprecise calibration. A discernible trend was apparent in this sample, suggesting that living donor recipients have increased probability of experiencing graft failure in the first 5 years (p = 0.069). Conclusion The 4-variable KFRE may be of interest in predicting kidney failure progression in pediatric kidney transplant recipients using data at 1-year post-transplant, however to substantiate these findings and ensure the robustness of conclusions, larger-scale studies should be conducted.