超声筛检肥胖儿童脂肪肝的价值评估  

Diagnostic value of ultrasonographic examination for hepatic steatosis in obese children

作　　者：张洪锡[1] 杨会萍 赖灿[1] 何瑾[1] 叶菁菁[1] 傅君芬[1] 

机构地区：[1]浙江大学医学院附属儿童医院,浙江杭州310003 [2]杭州市拱墅区米市巷街道社区卫生服务中心,浙江杭州310005

出　　处：《中国当代儿科杂志》2014年第9期873-877,共5页Chinese Journal of Contemporary Pediatrics

基　　金：国家自然科学基金(81270938);十二五国家科技支撑项目子课题(2012BAI02B03);"青春期医学"浙江省医学重点学科(创新学科)(11-CX24);浙江省医药卫生科技项目(2014KYA121)

摘　　要：目的评价常规超声在筛检肥胖儿童脂肪肝中的灵敏度和特异度。方法 162例肥胖儿童(年龄10.5±2.2岁,体重指数28±4)纳入该研究,均进行肝脏超声和磁共振氢谱(1H MRS)检查。1H MRS直接检测到的肝脏脂肪信号百分数通过相应的校准程序换算成甘油三酯重量百分数(mg/g湿重),表示肝脏脂肪含量(LFC)。以1H MRS结果为参考标准,计算超声筛检肥胖儿童脂肪肝的灵敏度、特异度、阳性预测值和阴性预测值。结果根据LFC>5%的量化诊断标准,1H MRS确定58.6%(95/162)的肥胖儿童患有脂肪肝,超声筛检脂肪肝的灵敏度为91.6%(87/95),特异度为50.7%(34/67),阳性预测值为72.5%(87/120),阴性预测值为81.0%(34/42)。不同超声等级的脂肪肝分组与LFC四分位数分组间存在明显的交互重叠。结论常规超声筛检肥胖儿童脂肪肝的灵敏度高,而特异度较低,提示常规超声可应用于肥胖儿童的脂肪肝筛检,必要时进行1H MRS检查加以明确。Objective To evaluate the sensitivity and specificity of hepatic ultrasonography（US） for the diagnosis of hepatic steatosis in obese children, using 1H magnetic resonance spectroscopy（1H MRS） as the reference standard. Methods A total of 162 obese children with age of 10.5±2.2 years and BMI of 28±4 were enrolled in this study. They accepted hepatic US and 1H MRS examinations. The sensitivity, specificity, positive predictive value（PPV） and negative predictive value（NPV） of US were calculated for the overall presence of hepatic steatosis by comparison with 1H MRS results. Results Using quantitative criteria of liver fat content（LFC） 〉5% determined by 1H MRS, 95 children（58.6%）were diagnosed as having hepatic steatosis. The sensitivity and specificity of US in diagnosing steatosis were 91.6%（87/95） and 50.7%（34/67） respectively, with PPV of 72.5%（87/120）, and NPV of 81.0%（34/42）. Considerable overlap in LFC measured by 1H MRS was observed between different grades from US findings： absent（LFC interquartile range： 1.3%-3.9%）, mild（2.4%-10.7%）, moderate（7.1%-20.2%） and severe（7.6%-28.8%） steatosis. Conclusions The US can yield a high sensitivity and low specificity in the diagnosis of hepatic steatosis in obese children, suggesting it can be used as a screening tool for hepatic steatosis. To improve diagnostics, 1H MRS is needed to determine LFC.

关 键 词：超声检测 磁共振氢谱 肥胖 脂肪肝 儿童 

分 类 号：R725.7[医药卫生—儿科]