Urinary L-type fatty acid-binding protein is a predictor of cisplatin-induced acute kidney injury

BACKGROUND: Although cisplatin-based chemotherapy is a standard treatment for urothelial carcinoma, it often causes acute kidney injury (AKI). AKI and dysfunction are observed in 25–35% of cisplatin-based chemotherapy patients, who may require treatment down-titration or withdrawal. In this study, we evaluated whether urinary L-FABP is a marker for early diagnosis of cisplatin-caused AKI. METHODS: We included 42 adult patients who underwent cisplatin-based chemotherapy for bladder cancer or upper tract urothelial carcinoma from January 2018 to March 2019. Urinary L-FABP and serum creatinine were measured at 2 and 6 h, and 1, 2, 3, 7 and 28 days after taking cisplatin. RESULTS: In the first week after receiving cisplatin, 10 patients (23.8%) were diagnosed with AKI (AKI(+) group). Pre-treatment (baseline) measurements did not significantly differ between the AKI(+) and AKI(−) groups. However, urinary L-FABP concentrations rapidly increased in the AKI(+) group and were significantly greater than in the AKI(−) group at Hour 2, Hour 6, Day 1 and Day 2. Serum creatinine also significantly differed between the AKI(+) group and the AKI(−) group on Days 3 and 7. ROC analysis was performed to evaluate the superiority of urinary L-FABP magnification which had the highest at the hour 6. The urinary L-FABP magnification and levels of aria under curve was 0.977. Based on ROC analysis, the best cut-off value of urinary L-FABP magnification was 10.28 times urinary L-FABP levels at the hour 0 (base line urinary L-FABP). CONCLUSIONS: Acute renal function deterioration was predicted by increased urinary L-FABP excretion within 6 h after receiving CIS-CT and, in those with AKI, the increase in urinary L-FABP excretion preceded the rise in sCr by over 2 days. In contrast, no appreciable changes in urinary L-FABP levels were observed in patients with stable renal function throughout the whole observation period. So early increase in urinary L-FABP may identify patients at risk of cisplatin-induced AKI, who might benefit from treatment to prevent nephrotoxicity. TRIAL REGISTRATION: This study was retrospectively registered.