Shear wave elastography as a diagnostic tool in biliary atresia and liver fibrosis

Abstract

Background

The study aims to investigate Shear Wave Elastography's accuracy in assessing pediatric cholestasis and differentiating biliary atresia from other causes. The early diagnosis of cholestasis in newborns, when caused by true liver disease and not physiological or transient jaundice is usually eluded. To maximize the diagnostic reliability of ultrasound as an initial imaging modality to diagnose biliary atresia, ultrasound elastography has been introduced as a quantitative non-invasive sonographic technique to measure liver stiffness which is presumed to be different in biliary atresia from other cholestasis as well as follow-up liver stiffness post-Kasai operation.

Results

Ten patients (34.48%) were diagnosed with cholestasis with normal/low GGT. Five patients (17.24%) were diagnosed with hepatitis, and 2 patients had syndromes (10.34%). Other causes were found in 11 patients (37.93%). Major bile duct obstruction with fibrosis/cirrhosis was the majority of findings found in biliary atresia patients (100%), most of them with mild fibrosis (40%), followed by moderate (36.67%), then marked fibrosis (13.33%) and secondary cirrhosis (10%). ROC curve analysis shows that the best cut-off value for SWE = 1.97 with a sensitivity of 75.0% and specificity of 83.5%, with positive and negative predictive values were 82.8% and 74.1%, respectively. Mean shear wave elastography was significantly higher among the biliary atresia group (median 2.86) than in non-biliary atresia (median 1.81) and control groups (median 1.64) (P < 0.001) The best cut-off value of shear wear elastography for predicting outcome in pediatric patients post-Kasai procedure was 3.55, with a sensitivity of 66.7%, specificity of 64.7%, positive and negative predictive values were 25% and 91.7% respectively, with accuracy 65%.

Conclusion

The results of this study suggest that shear-wave elastography is a useful diagnostic tool for differentiating biliary atresia from other causes of cholestasis in pediatric patients, with a high sensitivity and specificity. Further studies are needed to validate the findings and determine the optimal cut-off value for shear wear elastography in clinical practice.