The importance of urine caspase-3 and cytochrome C levels in the pathogenesis of ureteropelvic junction obstruction

Introduction: The aims of this study are to investigate the cytochrome c and caspase-3 levels in the urine samples of patients with unilateral hydronephrosis, and to examine the differences in urinary biomarker levels in the evaluation of postoperative treatment success in patients who underwent surgical intervention. Method: A total of 66 urine samples (before and after surgery) were collected from 33 patients with clinically demonstrated obstruction of ureteropelvic junction. All patients had unilateral hydronephrosis, and underwent open pyeloplasty (Pyeloplasty group). Ultrasonography results were obtained in terms of anteroposterior pelvis diameter (APD) and scintigraphic differential renal function (DRF). First control group included 32 patients with non-obstructive hydronephrosis [non-obstructive dilation (NOD) group], whereas 34 healthy children formed the second control group. Cytochrome c and caspase-3 measurements were performed using the ELISA method and the results were calculated by diving by serum creatinine levels. Results: Urinary caspase-3 levels were significantly higher preoperatively when compared to postoperative levels as well as NOD and control groups. In the postoperative period, the urinary caspase-3 levels decreased and were detected similar to the control groups. There was no significant change in urinary cytochrome c levels between all groups. Although there was a negative correlation between APD and DRF in the pyeloplasty group, there was no correlation between these parameters and other urinary groups. In ROC (Reciever Operating Curve) analysis, urinary caspase 3 level showed moderate diagnostic sensitivity and specificity for distinguishing patients that require pyeloplasty. Conclusion: Urinary caspase-3 levels increased while cytochrome c levels did not change significantly in patients with Ureteropelvic Junction (UPJ) obstruction which support that extrinsic apoptosis pathway plays a role in the cell death mechanism in urinary obstruction.