中文摘要：

目的通过对体外循环下接受心脏手术的患者，检测尿中性粒细胞明胶酶相关脂质运载蛋白（NGAL），观察其与急性肾损伤（AKI）的关系。方法根据AKI的诊断标准，将33例在体外循环下接受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，测定所有标本中的肌酐水平和尿液标本中NGAL水平。结果①33例患者有9例发生AKI，发生率为27％，AKI组血清肌酐（Scr）升高峰值出现在12-48h内。②与术前相比，非AKI组患者术后2h尿NGAL水平显著升高（P〈0．001），此后逐渐下降，其余各时间点与术前水平相比差异无统计学意义；AKI组术后2h及术后4h尿NGAL水平显著升高（均P〈0．001），术后8h仍持续较高水平，但与术前水平相比差异无统计学意义。③AKI组术后各时间点的尿NGAL水平都明显高于非AKI组（均P〈0．01）。④与术前相比，非AKI组患者术后2h及4h尿NGAL／Ucr水平显著升高（均P〈0．05），此后逐渐下降，与术前水平相比差异无统计学意义。AKI组术后2h及术后4h尿NGAL／Ucr水平显著升高（均P〈0．01），此后逐渐恢复到术前水平。⑤AKI组术后各时间点的尿NGAL／Ucr水平明显高于非AKI组，差异有统计学意义（均P〈0．01）。⑥2h尿NGAL和尿NGAL／Ucr的cutoff值分别在250μg/L和250μg／mmol时，体现出较好的敏感性和特异性。⑦AKI组术后12hScr水平与术后2h尿NGAL水平间存在线性相关（R=0．638，P〈0．05）。结论①体外循环下接受心脏手术的患者AKI发生率较高，可达到27％；②术后2h尿NGAL和术后2h尿NGAL／Ucr可作为体外循环下心脏手术后AKI发生的早期诊断指标，其中术后2h尿NGAL／Ucr更具敏感性；③术后2h尿NGAL和NGAL／Ucr分别在250μg／L和250μg／mmol时，体现出较好的敏感性和特异性。

英文摘要：

Objective To test the hypothesis that Neutiophil gelatinase -associated lipocalin （NGAL） is an early biomarker for acute kidney injury （AKI） in patients after cardiac surgery. Methods 33 cases undergoing cardiac surgery were divided into AKI group and Non-AKI group according to the AKI criteria The concentration of urine NGAL at different time points were measured. Results ①Nine of 33 cases （27%） developed postoperative AKI, but diagnosis with serum creatinine was only 12-48 hours after cardiac surgery. ②Urinary concentrations of NGAL at 2 h after cardiac surgery in patients who did not develope AKI were significantly higher compared with those of preoperative （P 〈 0. 001 ）. Urinary concentrations of NGAL at 2 h and 4 h after cardiac surgery in patients who developed AKI were significantly higher compared with those of preoperative （ P 〈 0. 001 ）. ③The mean urinary NGAL concentrations in patients who developed AKI were significantly higher after surgery compared with patients who did not develop AKI （P 〈 0.01 ）. ④Urinary concentrations of NGAL/Ucr at 2 h and 4 h after cardiac surgery in patients who did not develope AKI were significantly higher compared with those of preoperative （ P 〈 0. 05 ）. Urinary concentrations of NGAL/Ucr at 2 h and 4 h after cardiac surgery in patients who developed AKI were significantly higher compared with those of preoperative（ P 〈 0. O1 ）. ⑤The mean urinary concentrations of NGAL/Ucr in patients who developed AKI were significantly higher after surgery compared with patients who did not develop AKI（P 〈0. 01 ）. ⑥For concentrations in urine of NGAL at 2 h after surgery, sensitivity was 0. 7125, and specificity was O. 7307 for a cutoff value of 250 μg/L For concentrations in urine of NGAL/Ucr at 2 h after surgery, sensitivity was O. 8127, and specificity was O. 7839 for a cutoff value of 250 μg/mmol. ⑦Urinary concentrations of NGAL at 2 h after cardiac surgery was significantly associated with serum creatinine 12 h postope