尿中性粒细胞明胶酶相关脂质运载蛋白和IL-18对脓毒血症患者伴急性肾损伤的早期诊断意义

目的探讨尿中性粒细胞明胶酶相关脂质运载蛋白（NGAL）和白细胞介素18（IL-18）对脓毒血症患者并发急性肾损伤（AKI）的早期诊断价值。方法收集该院重症监护病房符合入选标准的112例患者在确诊脓毒血症后不同时间点的血、尿标本,分别测定血肌酐（SCr）、尿NGAL和尿IL-18水平。根据AKI的诊断标准,将患者分为AKI组和非AKI组,观察两组血SCr、尿NGAL和尿IL-18的动态变化。用受试者工作特征曲线（ROC）评价尿NGAL和IL-18对AKI的诊断作用。结果 112例脓毒血症患者中,发生AKI的有57例,发生率为50.9%。AKI组SCr在脓毒血症确诊后的第24 h上升至基础值的1.84倍,达到AKI的诊断标准。AKI患者尿NGAL和尿IL-18分别在脓毒血症诊断后2 h、8 h开始显著增高并在随后的时间点都高于基线值（均P〈0.05）,也显著高于非AKI组（均P〈0.05）。脓毒血症确诊后2 h,尿NGAL诊断AKI的ROC曲线下面积为0.930,95%可信区间为0.879～0.980,以65μg/L作为AKI的诊断界值时,敏感度和特异度分别为94.8%和86.2%;脓毒血症确诊后8 h,尿IL-18的ROC曲线下面积为0.922,95%可信区间为0.859～0.985,以2 400 ng/L作为AKI的诊断界值时,敏感度和特异度分别为93.2%和85.1%。结论脓毒血症确诊后2 h尿NGAL水平和确诊后8 h尿IL-18水平对AKI具有预测价值,其诊断时间远早于SCr。尿NGAL和尿IL-18可作为脓毒血症患者并发AKI的早期诊断标记物。

Significance of Early Diagnosis of Urinary Neutrophil Gelatinase-associated Lipocalin and Urinary Interleukin-18 in Patients with Sepsis Complicated with Acute Kidney Injury

Objective To determine whether urinary neutrophil gelatinase-associated lipocalin（NGAL） and urinary interleukin-18（IL-18） are early markers of acute kidney injury（AKI） with sepsis.Methods A total of 112 eligible patients were enrolled in this prospective study.Blood and urine samples were collected at different time as soon as sepsis was diagnosed.The concentrations of serum creatinine（SCr）,urine NGAL and urine IL-18 were measured.According to AKI criteria,patients were divided into the AKI group and non-AKI group.Dynamic changes of levels of Scr,urine NGAL and urine IL-18 were observed in two groups.The receiver operating characteristics were used to evaluate the early diagnostic value of urine NGAL and urine IL-18.Results Among 112 patients with sepsis,57（50.9%） had concomitant AKI.24h after sepsis diagnosed was made,the level of SCr rose to 1.84 times of the baseline,which met the diagnostic criteria of AKI.In the AKI group,urinary concentrations of NGAL at the 2nd hour and that of IL-18 at the 8th hour after the diagnosis of sepsis began to rise significantly from baseline.And at the following time spans,urinary concentrations of NGAL and IL-18 were significantly higher than the baseline levels and that in the non-AKI group（all P0.05）.At the 2nd hour,the area under the curve of urine NGAL was 0.930（95%CI 0.879～0.980）,the sensitivity was 94.8% and specificity was 86.2% with a cutoff value of 65 μg/L.At the 8th hour,the area under the curve of urine IL-18 were 0.922（95%CI 0.859～0.985）,the sensitivity was 93.2% and specificity was 85.1% with a cutoff value of 2 400ng/L.Conclusions Urinary concentrations of NGAL at the 2nd hour and that of IL-18 at the 8th hour after the diagnosis of sepsis have predictive value of AKI and their diagnostic time is much earlier than that for SCr.Therefore,urinary NGAL and IL-18 can be used as early biomarkers of septic AKI.