彩色多普勒超声在移植肾急性排异反应中的应用

Application of color Doppler ultrasonography in the acute rejection of renal transplantation

目的应用彩色多普勒超声寻找移植肾急性排异反应较为特异的诊断指标。方法经移植肾穿刺活检证实的急性排异反应患者42例,经长期随访(1年以上)和临床检查证实的功能稳定期患者115例。对两组移植肾长径、宽径、厚径、实质厚度以及主肾动脉和弓状动脉的阻力指数(RI)进行统计学比较;选取肾体积增大,锥体肿大回声减低、RI<0.7、RI≥0.7及RI≥0.8作为诊断标准,按诊断试验评价原则分别计算灵敏度、特异度、误诊率、漏诊率和符合率;并绘制ROC曲线,确定诊断界值。结果两组的移植肾长径、宽径、厚径及实质厚度差异有统计学意义(P<0.05);急性排异反应组肾内血流灌注减少,肾动脉舒张期血流速度明显下降,RI明显增高,与移植肾功能稳定期比较差异有统计学意义(P<0.05);各诊断标准对应的灵敏度分别为55.30%,55.20%,42.10%,57.90%和31.60%;特异度分别为71.30%、87.10%、25.70%、74.20%、98.20%。结论肾体积增大、肾锥体肿大、回声减低、RI升高对诊断移植肾急性排异反应有特异性。

Objective To find the spectacular indexes in the diagnosis of acute rejection of renal transplantation with color Doppler uhrasonography. Methods Forty-two patients with renal rejection were confirmed with percutaneous needle biopsy and 115 patients with stable renal function were confirmed with following up （〉 1 year） and clinical examination. The length, width, thickness, cortex thickness and resistive index （RI） of two groups were analyzed statistically. Then the specificity, sensitivity, misdiagnosis rate, false negative rate and consistency rate of renal volume, pyramid swelling, echo weakening, RI〈0.7, RI≥0.7 and RI≥0.8 were calculated. Results The length, width and thickness were statistically different in two groups （P〈0.05）. In patients with renal rejection, the marginal blood vessels in renal cortex decreased, and the blood velocity reduced obviously in the diastolic phase and RI increased obviously （P〈0.05）. The sensitivity of the above indexes were 55.30%, 55.20%, 42.10%, 57.90%, 31.60%, respectively, while the specificity were 71.30%, 87.10%, 25.70%, 74.20% and 98.20%, respectively. Conclusion Enlargement of renal volume, swelling of renal pyramids, echo weakening and RI increasing are specific indexes for diagnosis of acute rejection of renal transplantation.