Supplementary Material for: Furosemide Stress Test as a Predicting Biomarker for Delayed Graft Function in Kidney Transplantation

Background: Delayed graft function (DGF) could worsen early and long-term outcomes of kidney transplantation (KT). DGF is caused by several pre-transplantation and perioperative factors in both donors and recipients. At present, there are no biomarkers or tests during the immediate post-KT period that can accurately predict the development of DGF. Materials and methods: This prospective study was conducted in deceased donor KT (DDKT) at King Chulalongkorn Memorial Hospital, Thailand. All recipients underwent furosemide stress test (FST) by receiving a single dose of intravenous furosemide, 1.5 mg/kg at 3 h after allograft reperfusion. We determined the correlations between DGF (requiring dialysis within the first week after transplantation) and the values of urine volume recorded hourly after FST until 6 h, the parameters of postoperative dynamic tests, including resistive index (RI) of renal arteries and effective renal plasma flow (ERPF), and urine neutrophil gelatinase-associated lipocalin (NGAL). Results: Of the 59 total DDKT recipients enrolled, 24 developed DGF. The FST is a more accurate biomarker than urine NGAL, RI of renal arteries, and ERPF in the prediction of DGF. The 4-h urine volume less than 350 mL (FST non-responsive) was the best cut-off value in predicting DGF with 87.5% sensitivity, 82.9% specificity, and 82.5% accuracy. Multiple logistic regression analyses showed an odds ratio of 0.993 (0.986–0.999, p = 0.035) for the 4-h urine volume to predict DGF. Conclusions: The FST is a simple and accurate biomarker for predicting DGF in early post-KT period. Close monitoring and well prepared dialysis are suggested in patients with urine volume < 350 mL after 4 h of FST. The FST non-responsive patients could be the target for further DGF preventive intervention. ClinicalTrials.gov identifier: NCT03071536.