Reliability of urinary neutrophil gelatinase-associated lipocalin level in patients with ileal conduit urinary diversion

Objective: Inevitable metabolic changes occur in patients after radical cystectomy (RC) and urinary diversion (UD) surgery. The relationship between serum creatinine (SCr) and serum cystatin C (ScysC) and urinary neutrophil gelatinase-associated lipocalin (uNGAL) measurements was evaluated in order to diagnoseearly, prevent andslow down the metabolic complications that may occur. Materials and Methods: The study included 14 patients who underwent open RC and UD in Manisa Celal Bayar University, Faculty of Medicine, Urology Clinic between January 2022 and September 2022, without hydronephrosis at diagnosis and follow-up. SCr and ScysC measurements were made from the same tube, 3 days before surgery, 1 month and 3 month after surgery. Simultaneous with these blood samples, urine samples were collected and stored at -80°C until uNGAL analysis. All urine samples were analyzedby the same specialist doctor at the same time. Results: It was determined that SCr and ScysC measurements and estimated glomerular filtration rates (eGFR, eGRFcr and eGFRcys) of the patients who underwent RC and ICUD showed a significant correlation in the preoperative and postoperative period. There was no correlation between uNGAL analyzes and SCr, ScysC, eGFRcr, eGFRcys results. Differences in CKD staging were observed between eGFRcr and eGFRcys, which may be important in clinical practice. Conclusion: CKD is among the important complications of RC and UD. UD makes this patient group special because of the metabolism of fluids, electrolytes, urinary solutes, and creatinine.Our findings suggest that ScysC and eGFRcys would be more reliable inthe evaluation of renal function in patients who underwent RC and UD. For the reliability of the calculations, studies with a larger patient population and comparisons of eGFR calculations using SCr, ScysC, both SCr and ScysC and MAG3 dynamic renal scintigraphy are needed. Keywords: Correlation, cystatin C, NGAL, radical cystectomy, urinary diversion