超声造影定量分析在早期识别兔脓毒血症致急性肾损伤中的应用价值

Quantitative analysis of ultrasonography to evaluate the renal functional status of acute renal injury induced by sepsis in rabbits

目的探讨超声造影定量分析在早期识别兔脓毒血症致急性肾损伤中的应用价值。方法选择健康新西兰白兔40只,采用盲肠结扎穿孔术制作脓毒血症兔模型。于模型制备后0h、2h、4h、6h、12h检测血肌酹(Scr)、尿素(Urea)、尿中性粒细胞明胶酶相关脂质运载蛋白(NGAL)、肾损伤分子-l(KIM-l)、白细胞介素-18(IL-18),行肾脏病理学检查,同时采用超声显像仪对双肾皮质进行实时超声造影灌注成像,应用图像分析软件计算感兴趣区域内造影剂回声信号强度,获得肾灌注时间-密度曲线及反映肾脏血流灌注的相关参数,使用数字化医学成像及交互格式记录肾灌注各个时间点的数据,并进行统计分析。结果(1)肾损伤指标变化:尿液KIM-1、NGAL.IL-18于模型制备后6h开始明显高于建模前(P<0.05),12h更为显著(P<0.05);Scr、Urea于建模后12h明显高于建模前(P<0.05)。(2)肾皮质灌注的实时观察及灌注参数分析:经肘静脉团注超声造影剂,建模后4h,双肾的肾皮质曲线下面积较建模前明显增大(P<0.05),达峰时间较建模前明显延长(P<0.05),而α、A均明显低于建模前(P<0.05),6h、12h更显著(P<0.01),曲线达峰绝对值于建模后6h、12h明显低于建模前(P<0.05).结论超声造影定量分析技术可早期识别兔脓毒血症导致的急性肾损伤。

Objective To explore the value of quantitative analysis of contrast-enhanced ultrasound in early identification of acute renal injury caused by sepsis in rabbits. Methods Forty healthy New Zealand whiterabbits were selected to make sepsis rabbit models by cecal ligation and perforation. Serum creatinine (Scr), Urea, urine neutrophil gelatinase-related lipid carrier prot&n ( NGAL), kidney injury molecule-1 (KIM-1) and interleukin-18(IL-18) were detected by blood sampling at 0,2,4,6 and 12 h after model preparation. Renal pathology was examined. At the same time, real-time conti'ast-enhanced ultrasound perfusion imaging of bilateral renal cortex was performed by ultrasound imaging instrument. The echo signals of contrast agents in the region of interest were calculated by image analysis software. Intensity, time-density curve of renal perfusion and parameters reflecting renal perfusion were obtained. Digital medical imaging and interactive format were used to record the data of renal perfusion at each time point, and compared with renal function indexes and results of pathological examination. Results ( 1 ) Changes of renal function:KIM-1 ,NGAL and IL-18 in the urine of sepsis rabbits began to increase significantly 6 h after modeling,and much more higher at the 12th hour than before( P<0.05 ). The concentration of Scr and Urea in sepsis rabbits increased significantly 12 h after modeling, which was significantly higher than that befbre modeling(P<0.05).(2) Real-time observation of renal cortical perfusion and analysis of perfusion parameters: Ultrasound contrast agent was injected through elbow vein, and the model was established 4 h later, area under curve of kidney cortex increased significantly ( P<0.05 ), peak time prolonged significantly (P<0.05),a and A were significantly lower than those before modeling( P <0.05) and even lower at 6 h and 12 h after modeling(P <0.01). Meawhile,absolute peak value of curve at 6 h and 12 h after modeling was significantly lower than that before modeling(P <0.05). Conclusion Quantitative analysis of contrast-enhanced ultrasound can identify early actue kidney injury caused by sepsis in rabbits.