BOLDMRI评价原发性肾病综合征的肾内氧代谢状态

BOLD MRI in evaluation of renal oxygenation in primary nephrotic syndrome

目的采用BOLD MRI评估原发性肾病综合征(PNS)患者肾内氧代谢状态。方法收集20例初次发病且未接受治疗的PNS患者和18名健康志愿者进行BOLD MR检查,分别测量肾脏皮质和髓质的R2*值,记录检查当日PNS患者的评估肾小球滤过率(eGFR)等实验室指标。PNS患者在检查后1周内进行穿刺活检,肾小管间质病理损害评分采用Katafuchi积分标准。比较PNS患者和正常人间R2*值的差异,分析PNS患者R2*值与肾小管间质病理损害积分、eGFR等临床指标的相关性,并对PNS患者的预后情况进行随访。结果 PNS患者髓质R2*值明显低于正常人(t=-9.270,P<0.001);PNS患者髓质R2*值与eGFR呈负相关(r=-0.462,P=0.040),与肾小管间质病理损害积分呈正相关(r=0.809,P<0.001)。随访结果显示髓质R2*值相对增高的PNS患者预后常较差。结论 BOLD MRI能反映PNS患者肾内氧合水平及肾功能、病理损害程度,为评估PNS患者预后提供更多辅助信息。

Objective To evaluate the renal oxygenation in patients with primary nephrotic syndrome（PNS）using BOLD MRI.Methods Twenty patients with untreated first-onset PNS and 18 healthy control subjects underwent BOLD MRI.The R2＊of renal cortex and medulla were measured.Blood and urine samples were obtained on the day of MRI,and the patients underwent renal biopsy after MRI.The renal tubulointerstitial damage scores（TIDS）were determined using Katafuchi criteria.All patients received corticosteroids within 7days after MRI and were followed up for 12 months.The difference of R2＊levels between the PNS patients and controls were compared,and the correlations between R2＊values and TIDS,laboratory parameters（eGFR,etc.）were tested.Results R2＊values of renal medulla in PNS patients significantly decreased compared that of the controls（t=-9.270,P〈0.001）.R2＊values of renal medulla in PNS patients were negatively correlated with eGFR（r=-0.462,P=0.040）and positively correlated with TIDS（r=0.809,P〈0.001）.There was a slight tendency for higher R2＊values of renal medulla in individuals with poor prognosis.Conclusion BOLD MRI is a noninvasive method for the detection of renal oxygenation changes,which can evaluate the renal function and tubulointerstitial impairment,as well as prediction of the prognosis for PNS patients.