尿胰岛素样生长因子结合蛋白7对脓毒症所致急性肾损伤的早期诊断价值

Early diagnostic value of urinary insulin-like growth factor binding protein-7 in patients with sepsisinduced acute kidney injury

目的评价尿胰岛素样生长因子结合蛋白7（IGFBP-7）在脓毒症所致急性肾损伤（AKI）的早期诊断价值，同时比较尿IGFBP-7与血清胱抑素C（sCys-C）、血清肌酐（sCr）在脓毒症所致AKI患者的预测作用。方法选择2015年9月至2016年8月入住天津市第一中心医院ICU的105例脓毒症患者，根据AKI的诊断标准，将研究对象分为AKI组（48例）和非AKI组（57例）；分别在入ICU的0、3、6、12、24、48h采集患者的血标本和尿标本，测定不同时间点尿IGFBP-7、sCys-C、sCr的水平。通过受试者工作特征曲线（ROC）和曲线下面积（AUC）评价尿IGFBP-7、sCys-C和sCr对脓毒症所致AKI患者的早期诊断价值。结果随入ICU时间的延长，AKI患者尿IGFBP-7、sCys-C和sCr的水平逐渐上升。两组IGFBP-7水平在3h时差异有统计学意义[2．34（2．03，4．19）ng／mL和1．79（1．51，2．62）ng／mL，P〈0．05]；两组sCys-C水平在6h时差异有统计学意义[（1．63±0．42）ng／mL和（1．20±0．46）ng／mL，P〈0．05]；两组sCr水平在12h时差异有统计学意义[80．5（74．3，88．0）ng／mL和77．0（67．0，84．0）ng／mL，P〈0．05]。脓毒症所致AKI患者尿IGFBP-7、sCys-C曲线下的面积分别为0．881（95％CI：0．813～0．949）和0．782（95％CI．0．692～0．872），优于sCr曲线下面积0．629（95％CI：0．522～0．737）。尿IGFBP一7的截断值为1．82ng／mL时，其灵敏度为93．8％，特异度为77．2％。结论尿IGFBP-7、sCys-C在早期预测脓毒症所致AKI的价值优于sCr，而尿IGFBP-7的灵敏度和特异度高于sCys．c，提示尿IGFBP-7可以作为脓毒症所致AKI早期诊断的标志物。

Objective To evaluate the early diagnostic value of urinary insulin-like growth factor binding protein-7 （IGFBP-7） in sepsis-induced acute kidney injury （AKI） , and to compare the effects of urinary IGFBP-7 to that of serum cystatin-C （sCys-C） and serum creatinine （sCr） on predicting the severity of sepsis-induced AKI patients. Methods A total of 105 patients with sepsis admitted to ICU in Tianjin First Hospital from September 2015 to August 2016 were divided into AKI group （ n = 48 ） and non-AKI group （ n = 57） according to the AKI diagnostic criteria. The samples of blood and urine of the patients were collected at 0, 3, 6, 12, 24 and 48 h, to measure the levels of urinary IGFBP-7, and serum Cys-C and sCr. Based on the receiver operating characteristic curve （ROC） and the area under the curve （AUC） , the early diagnostic value of urinary IGFBP-7, and serum sCys-C and sCr in sepsis-induced AKI patients was determined. Results With the increase in length of ICU stay, the levels of urinary IGFBP-7, and serum sCys-C and sCr in AKI patients increased gradually. There was a significant difference between the two groups in the level of IGFBP-7 at 3 h [2. 34 （2.03, 4. 19） ng/mL vs. 1.79 （ 1.51, 2. 62） ng/mL, P 〈 0. 05 ]. At 6 h, the difference in sCys-C between two groups was statistically significant [ （ 1.63 ± 0. 42） ng/mL vs. （1.20 ±0. 46） ng/mL, P 〈 0. 05 ]. At 12 h, the difference in sCr between two groups was statistically significant [ 80. 5 （74. 3, 88.0） ng/mL vs. 77.0 （ 67. 0, 84.0） ng/mL, P 〈 0. 05 ]. The AUCs of urinary IGFBP-7 and sCys-C of sepsis-induced AKI patients were 0. 881 （ 95% CI： 0. 813 - 0. 949） and 0. 782 （95% CI： 0. 692 -0. 872）, which were superior to those in AUC of sCr 0. 629 （95% CI： 0. 522 -O. 737） . When the cutoff value of urinary IGFBP-7 was 1.82 ng/mL, the sensitivity was 93.8% and the specificity was 77. 2%. Conclusions Urine IGFBP-7 and sCys-C have higher predictive value in sepsis-induced AKI than sCr, whereas urine IGFBP-7 is more sensitive and specific than sCys-C, suggesting that IGFBP-7 may be used as sepsis signs of early diagnosis of AKI.