Diagnostic accuracy of ultrasound in diagnosing biliary atresia taking histopathology as gold standard

Abstract

Background: Biliary Atresia (BA) is the commonest surgical reason in newborns presenting with cholestatic jaundice. Accurate diagnosis can be made using imaging studies. The unique advantages of ultrasonography include its lower cost, non-invasiveness, and accessibility as a non-ionizing bedside instrument. This study was designed to determine diagnostic accuracy of ultrasonography in diagnosing biliary atresia taking histopathology as gold standard.

Methodology: This descriptive cross-sectional study was performed at the Department of Diagnostic Radiology, CH & ICH, Multan, over a three-month period from 4th December 2024 to 3rd March 2025. Infants (n=111) up to 12 weeks of age with suspected BA were enrolled consecutively. Cases with neonatal hepatitis were excluded. Pre- and post-meal abdominal ultrasound was performed by a consultant radiologist using a 7–15 MHz linear probe in multiple planes, with non-visualization/contracted gall bladder and a triangular cord sign for BA. All infants underwent transcutaneous core needle liver biopsy under local anesthesia. Data was analyzed using SPSS version 23. Mean ± SD is reported for age and frequency with percentages for gender, BA on USG abdomen and histopathology. Keeping histopathological findings as gold standard, diagnostic accuracy of USG abdomen is reported as sensitivity, specificity, positive & negative predictive values and accuracy.

Results: The mean age of the infants was 7.8±2.9 weeks with 62.2% males. Biliary Atresia was positive in 64% (n=71) on ultrasound and 69.4% (n=77) on histopathology. USG demonstrated 87.01% sensitivity, 88.2% specificity, 94.4% PPV, 75.0% NPV, and 87.4% accuracy.

Conclusion: Ultrasound is a reliable non-invasive modality for diagnosing BA, demonstrating high sensitivity and specificity compared to histopathology.