Urinay neutrophil gelatinase-associated lipocalin as a biomarker in different renal problems.

BACKGROUND/AIM Neutrophil gelatinase-associated lipocalin (NGAL) is used previously to estimate the etiology, severity, and clinical outcomes of acute kidney injury (AKI). However, the role of urinary NGAL (uNGAL) in the post-renal setting is not clear. In our study, we aimed to discover the cut-off value of uNGAL that can be used in the differential diagnosis of underlying AKI etiologies. MATERIALS AND METHODS In this prospective cross-sectional study, we examined 82 subjects in four groups: Patients that had (1) post-renal AKI; (2) AKI other than post-renal etiologies; (3) stable chronic kidney disease; and (4) healthy subjects. A renal function assessment was carried out by measuring serum creatinine (sCr) and uNGAL at the time of diagnosis (0th minute (T0)). We followed the study group for three months. RESULTS At the time of diagnosis, sCr (T0) was highest in the post-renal AKI and AKI groups in contrast to stable chronic kidney disease patients and healthy subjects (p<0.001), as expected. T0 median uNGAL was highest in the post-renal group (p<0.001). Area under curve (AUC) of uNGAL to estimate post-renal AKI presence was 0.957 (95% CI, 0.897?1.000; P < 0.001). The cut-off point of uNGAL was 42.625ng/ml for this estimation. CONCLUSION Patients with AKI must be classified according to the underlying etiologies as soon as possible. uNGAL may be useful to estimate the etiologies, and whether the problem is acute or chronic in the course. In post-renal kidney problems, to plan the urgency of the urologic procedures, it is crucial.