肝脏硬度测量在胆道闭锁与其他婴儿胆汁淤积鉴别诊断中的应用价值

目的 评价肝脏硬度测量在鉴别胆道闭锁与其他婴儿胆汁淤积时的应用价值,并与生化指标做对比研究.方法 选取2015年1月至2015年12月收治于首都医科大学附属北京儿童医院行手术探查及术后肝脏病理确诊的婴儿胆汁淤积患儿62例,男30例(48.4%),女32例(51.6%),平均手术时年龄(72.7±20.1)d;入组其他婴儿胆汁淤积患儿22例,男21例(95.5%),女1例(4.5%),平均手术时年龄(84.6±41.7)d.回顾性研究患儿术前3 d内的肝脏硬度测量值及生化指标,采用独立样本t检验、ROC曲线分析及配对卡方检验,对比评价肝脏硬度测量在鉴别胆道闭锁与其他婴儿胆汁淤积患儿时的应用价值.结果 比较两组患儿的肝脏硬度测量值、谷丙转氨酶(ALT)、谷草转氨酶(AST)、γ-谷氨酰转肽酶(GGT)、总胆红素(TBIL)、总胆汁酸(TBA),仅肝脏硬度测量值(12.29±6.99比8.05±2.97,P=0.007)和GGT(376.79±346.70比641.70±474.29,P=0.008)差异有统计学意义.对这两项指标进行ROC曲线分析,曲线下面积分别为AUROC(肝脏硬度测量)=0.743,AUROC(GGT)=0.696.取肝脏硬度测量界值8.1kPa时可获得最大约登指数0.427,超过此值提示患儿为胆道闭锁的敏感度0.79,特异度0.64,阳性预测值0.86,阴性预测值0.52;取GGT界值344.15μmol/dl时可获得最大约登指数0.359,超过此值提示患儿为胆道闭锁的敏感度0.68,特异度0.68,阳性预测值0.86,阴性预测值0.43.以手术探查实际结果为标准,分别对肝脏硬度测量(界值8.1kPa)和GGT(界值344.15μmol/dl)进行配对卡方分析(McNemar法),结果肝脏硬度测量8.1kPa(P=0.383),GGT344.15μmol/dl(P=0.019),提示当取肝脏硬度测量界值8.1kPa时对胆道闭锁和其他婴儿胆汁淤积的鉴别判断与实际情况无差异,而取GTT界值344.15μmol/dl时则与实际情况有差异.结论 肝脏硬度测量可较好的应用于胆道闭锁与其他婴儿胆汁淤积的术前鉴别,超过界值8.1kPa时能有效提示患儿为胆道闭锁.

Utility of liver stiffness measurement for differentiating biliary atresia from other causes of infantile cholestasis

Objective To evaluate the utility of liver stiffness measurement for differentiating biliary atresia (BA) from other cause of infantile cholestasis (IC).Methods A total of 62 IC patients confirmed by operation and liver pathology from January 2015 to December 2015 were retrospectively analyzed.Liver stiffness measurements and biochemical parameters were acquired at 3 days pre-operation.Mean values between BA group and other cause groups were statistically compared.Optimal cutoff values were calculated by receiver operating characteristic (ROC) analysis and evaluated by χ2 test of paired comparison.Results There were 30 boys and 32 girls with a mean operative age of 72.7±20.1 days.And among 22 IC patients due to other causes,there were 21 boys and 1 girl with a mean operative age of 84.6±41.7 days.Liver stiffness measurements and biochemical parameters of alanine aminotransferase (ALT),aspartate aminotransferase (AST),gamma-glutamyl transferase (GGT),total bilirubin (TBIL) and total bile acid (TBA) were compared between two groups.Statistical differences existed in liver stiffness (12.29±6.99 vs.8.05±2.97,P=0.007) and GGT level (376.79±346.70 vs.641.70±474.29,P=0.008).The ROC analysis showed that the cutoff values for differentiating two groups were 8.1kPa of liver stiffness and 344.15μmol/dl of GGT.The area under the ROC curve of liver stiffness was 0.743 with a sensitivity of 0.79,a specificity of 0.64,a positive predictive value of 0.86 and a negative predictive value of 0.52.And the area under the ROC curve of GGT was 0.696 with a sensitivity of 0.68,a specificity of 0.68,a positive predictive value of 0.86 and a negative predictive value of 0.43.According to the results of intraoperative findings and liver pathology,χ2 test of paired comparison was performed with P value of liver stiffness (8.1kPa,0.383>0.05) and GGT (344.15μmol/dl,P=0.019<0.05).It hinted at no differentiating difference between liver stiffness (8.1kPa) and actual findings,but GGT.Conclusions Liver stiffness measurement may be effectively used for differentiating BA from other causes of IC with a cutoff value of 8.1 kPa.