EndourologyOriginal articleInvestigation of urinary neutrophil gelatinase associated lipocalin (NGAL) for early diagnosis of acute kidney injury after percutaneous nephrolithotomy

IntroductionPercutaneous nephrolithotomy (PCNL) could be mentioned as the most important treatment of choice for kidney staghorn stones. Previous publications reported that the novel biomarker urinary neutrophil gelatinase-associated lipocalin (NGAL) activity significantly increases in acute kidney injury (AKI) but there is not many published articles related to increase of NGAL after PCNL procedure.ObjectiveThis study aimed to investigate AKI by urinary measurement of NGAL after PCNL procedure.Subjects and methodsBased on a cross-sectional design, 41 patients with staghorn renal stones were nominated. All patients have been informed and signed the consent form. NGAL levels were measured by urinary sampling at 2 h before and 12 h after the procedure. Serum creatinines (Cr) were measured 12 h before and 48 h after the surgery. Demographic and clinical data including surgical procedure were recorded in Excel and analyzed by SPSS (SPSS Inc., Chicago, IL) for windows.ResultsWith a minimum of 20 and a maximum of 70, the mean age of patients was 47 years old. 71% of patients studied were males. There was a significant change in mean serum Cr (1.06 versus 1.12 mg/dL; p < 0.01) before and after the procedure respectively. Glomerular filtration rate (GFR) with a mean of 81.93 umol/L before the procedure was decreased (p < 0.02) to 77.46 umol/L after the procedure. The changes in urine level of NGAL were significant (p < 0.02), associated to an increase in mean value of 20.63 ng/mL (two hours before) versus 56.28 ng/mL (twelve hours after)the PCNL procedure.ConclusionsWithin different extents after PCNL procedure there was a significant increase in the biomarker of NGAL levels.In order to reduce AKI and other post-operative complications, further studies in a large population of patients seem to be advantageous.