中文摘要：

目的探讨接受体外循环心脏手术患者尿中性粒细胞明胶酶相关脂质运载蛋白（NGAL）和尿白细胞介素18（IL-18）与急性肾损伤（AKI）的关系。方法根据AKI的诊断标准，将33例体外循环心脏手术的患者分为AKI组及非AKI组，分别留取术前及术后不同时间点的血液和尿液标本，测定Scr、尿NGAL和IL-18水平。结果33例中有9例发生AKI，发生率为27．27％。AKI组Scr升高峰值出现在12～48h内。与术前相比，AKI组术后2h、4h尿NGAL及IL-18水平升高，差异有统计学意义（P〈0．01）。与非AKI组比较，AKI组术后各时间点的尿NGAL水平、术后2h及4h的尿IL-18水平都较高，差异有统计学意义（P〈0．01）。经尿肌酐（Ucr）校正后，相应时间点的NGAL／Ucr和IL-18／Ucr差异仍有统计学意义（P〈0．01）。术后2h尿NGAL和尿NGAL／Ucr的界定（cutoff）值分别在250μg／L和250μg／mmol时；术后2h尿IL-18和尿IL-18／Ucr的界定值分别在1800ng／L和1800ng／mmol时，体现出较好的敏感性和特异性。AKI组术后12hScr水平与术后2h尿NGAL水平呈正相关（r=0．638，P〈0．05）。结论体外循环下接受心脏手术的患者AKI发生率较高；术后2h尿NGAL和NGAL／Ucr、术后2h尿IL-18和尿IL-18／Ucr当达到一定界定值时，均可作为体外循环下心脏手术后AKI发生的早期诊断参考指标，其中术后2h尿NGAL／Ucr为250μg／mmol时更敏感。

英文摘要：

Objective To examine the association of urinary neutrophil gelatinaseassociated lipocalin（NGAL） and interleukin 18（IL-18） with acute kidney injury （AKI） in patients after cardiac surgery. Methods Thirty-three patients undergone cardiac surgery were divided into AKI group and non-AKI group according to the AKI criteria. The Scr, urinary NGAL and IL-18 were measured at different time points. Results Nine of 33 patients （27.27%） developed postoperative AKI, and Scr concentration in AKI group reached its peak within 12-48 hours after cardiac surgery. Urinary eoneentrations of NGAL and IL-18 at 2 h and 4 h after cardiac surgery were significantly higher than those before operation in AKI patients （P〈0.01）. The urinary concentrations of NGAL at each time point and that of IL-18 at 2 h and 4 h after cardiac surgery in AKI patients were significantly higher than those in non-AKI patients. After correction by urinary creatinine, the differences of NGAL/Ucr and IL-18/Ucr ratios were still significant （P〈0.01）. For concentrations of urinary NGAL, IL-18 and ratios of NGAL/Ucr, IL-18/Ucr at 2 h after surgery, sensitivities and specificities were good with cutoff values at 250 μg/L, 250 μg/mmol and 1800 ng/L, 1800 ng/mmol, respectively. Urinary concentration of NGAL at 2 h after cardiac surgery was positively correlated with Scr at 12 h postoperation in AKI group （r=0.638, P〈0.05）. Conclusions The incidence of AKI in patients after cardiac surgery is quite high. Urinary concentrations of NGAL, IL-18 and ratios of NGAL/Ucr, IL-18/Ucr at 2 h after cardiac surgery are the early diagnostic markers for AKI, among which urinary NGAL/Ucr is the most sensitive one.