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

Abstract

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 8.1 kPa of liver stiffness and 344.15 μmol/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 (8.1 kPa, 0.383>0.05) and GGT (344.15 μmol/dl, P=0.019<0.05). It hinted at no differentiating difference between liver stiffness (8.1 kPa) 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. Key words: Biliary atresia; Cholestasis; Differential diagnosis