Clinical significant of urine neutrophil, gelatinase-associated lipocalin and urine interleukin-18 in detecting critically ill patients with acute kidney injury

Objective To investigate the significance that urine neutrophil gelatinase-associated lipocalin(uNGAL) and urine interleukin-18 (uIL-18) as early biomarkers for acute kidney injury(AKI) in critically ill patients and evaluate the predictive value of them in patients with established AKI.Methods Fiftynine Children with critically ill were selected as our subjects,who were hospitalized at PICU or health examination center in Women's and Children's Medical Center of Guangzhou from May 2012 to December 2013.The patients were divided into critically ill patients with AKI group (Group A),critically ill patients without AKI group(Group B) and 30 healthy children were served as control group(Group C).The level of uNGAL and uIL-18 were measured,and the relation between the changes of level and creatinine clearance rate (Ccr).Results Compared with critically ill patients without AKI group and control group,the level of uNGAL and uIL-18 in AKI group were (156.88 ± 59.67) μg/L and (3.95 ± 1.08) μg/L,higher than those in the without AKI group((26.38 ± 12.01) μg/L,(0.24 ± 0.15) μg/L; F =125.69,P ＜ 0.01) or control group ((20.08 ±8.03) μg/L,(0.17 ±0.13) μg/L;F=302.97,P＜0.01).Two days before the diagnosis of AKI,the area under the curve(AUC) of uNGAL and ulL-18 were 0.882 (95％ CI 0.787-0.977,P ＜ 0.05) and 0.840(95％ CI0.729-0.951,P ＜0.05).One day before the diagnosis of AKI,the AUC of uNGAL and ulL-18 were 0.867 (95％ CI 0.766-0.968,P ＜ 0.05) and 0.873 (95％ CI 0.767-0.979,P ＜ 0.05).The level of uNGAL and uIL-18 in AKT group were negative with Ccr at just before diagnosis 1 d (r =-0.578,P ＜0.05; r =-0.480,P ＜ 0.05),and those were also negative with Ccr at diagnosis day (r =-0.434,P ＜ 0.05 ; r =-0.660,P ＜0.05).Conclusion The uNGAL and uIL-18 are indicated markers in predicting AKI and short-term prognosis of AKI in critically ill patients. Key words: Neutrophil gelatinase-associated lipocalin;  Iinterleukin-18;  Acute renal injury;  Children