Use of Urine N-Terminal Prohormone of Brain-Natriuretic Peptide (NT-proBNP) as a Non-Invasive Indicator for Renal Function Recovery after Surgical Relief of Hydronephrosis

Cardiorenal syndrome is rarely discussed in patients with obstructive uropathy. On the other hand, there is currently no accurate and convenient clinical biomarker to predict the recovery of renal function after the resolution of ureteral obstruction. The purpose of this study is to explore the association between hydronephrosis and cardiorenal syndrome by measuring the change of the N-terminal prohormone of brain-natriuretic peptide (NT-proBNP), which is a biomarker typically used for cardiac failure, in patients receiving surgery to relieve obstructive uropathy. A total of 212 patients admitted for ureteroscopic (URS) procedures to relieve hydronephrosis were enrolled in this study. The severity of hydronephrosis as well as plasma and urine NT-proBNP levels were obtained before and after surgery. The results showed a significant correlation between urine NT-proBNP levels and renal function recovery following the resolution of hydronephrosis (OR 3.24, 95% CI 1.09-9.70, p = 0.035). Urine NT-proBNP could even predict the recovery of renal function with an area under the ROC = 0.775 (0.65-0.88, p < 0.001). In conclusion, urine NT-proBNP could be a useful early marker of renal function recovery after URS surgery, identifying patients whose renal and heart functions were compromised by the obstruction.