Importance of determination of urine neutrophile gelatinase associated lipocalin in early detection of acute kidney injury.

Acute kidney injury (AKI) is a complex, frequent and serious clinical problem with high rate of mortality. Therefore there is a serious need for early detection of AKI, with a tendency to detect early stage--RISK dut to start with therapy as soon as possible and prevent irreversible changes in renal function. Study's purposes were to explore the rhythm of urine neutrophile gelatinase associated lipocalin (urine NGAL) concentration changes before and after cardiovascular surgery and compare results of urine NGAL values with results of serum creatinine and creatinine clearance as main diagnostic indicators of renal function in order to define role of urine NGAL biomarker in early diagnosis of acute kidney injure. In the prospective clinical study 150 cardiovascular surgery patients were included. Basal value and concentration of urine NGAL were tested 3, 6 and 12 hours after cardiovascular surgery, and concentration of serum creatinine was tested once per day first three days after surgery. Also creatinine clearance value was calculated according to Cockrof-Goult formula. After above mentioned, rate of acute kidney injure was estimated according to RIFLE criteria. The study results showed that the value of urine NGAL was elevated above cutt-off after cardiac operation in a group of patients who developed AKI (defined according to RIFLE criteria). There were statisticaly significant difference between all four measerments (p < 0.05). There were also moderate positive correlation (0.500 and 0.502) between urine NGAL values and percentage difference of serum creatinine and creatinine clearence. All that indicate that higer values of urine NGAL are followed by higher percentage difference of serume creatinine and creatinine clearence. By using of automated urine NGAL test detection of acute kidney injure is posible 24-48 hours earlier comparing with actual results acquired by determination of serum creatinine concentration. The results of this study will indicate urine NGAL as a reliable biomarker of early acute kidney injure. A combination of early and late markers of kidney damage (urine NGAL, serum creatinine) can greatly contribute to better control the outcome of all those who are a risk group for the development of AKI.