Background and Goal of Study: Acute kidney injury (AKI) after coronary artery bypass grafting (CABG) is one of the main complication that increases morbidity and mortality. The serum creatinine which is frequently used as a marker of renal function does not reflect the status of kidney function during acute changes.  The aim of this study is to assess the correlation between three urinary biomarkers [Microalbumine (MA), Neutrophil gelatinase-associated lipocalin (NGAL), Kidney injury molecule-1(KIM-1)] and AKI in CABG patients.
Materials and Methods:  All patients >18 years of age, underwent with cardiopulmonary bypass between February 2016 and July 1016 were enrolled in the prospective study. The primary outcome was AKI, defined as  ≥ %25 decrease in glomerular filtration rate. The GFR was calculated as creatinine clearance rates with 24-hour urine collection. The single urine samples for MA and NGAL were obtained at postoperative 2-h and for KIM-1 at 24-h. 
 Results and Discussion: A total of 70 patients were included in this study.  AKI was identified in 18 (%25.7) patients while other 52 patients (74.3) were classified as non-AKI.
The MA and NGAL were significantly higher in AKI patients than in non-AKI patients 
(median [IQR], MA:  37.87 [15.81-78.94] ʋ 18.24 [11.04-38.63] [μg/ml], p=0.022; MA/Cr: 150.77 [65.91-535.08] ʋ 81.18  [41.95-180.26] [μg/mg], p=0.05; uNGAL 33.35 [7.3-67.58] ʋ 11.50 [6.98-18.13] [ng/ml], p=0.023; uNGAL/Cr: 81.66 [47.84-274.95] ʋ 52.95 [31.04-89.53] [ng/mg], p=0.023). The 2-h NGAL /Cr values correlated with length of stay in hospital (p=0.042) and 2-h MA/ Cr measurements correlated with length of İCU stay (p=0.02). 
Conclusion(s): Single measurements of  urine NGAL and MA in 2-h after  CABG may be useful for predicting the occurrence of AKİ while, urine KİM-1  which was measured in postoperative 24.hour was not associated with AKİ. 


08 / Comparison of urinary biomarkers for prediction of acute kidney injury after coronary artery bypass surgery.