Biliary atresia

Case contributed by Karina Dorfman


7-week old female infant presented with new jaundice. Laboratory studies showed elevated direct bilirubin, transaminases, alkaline phosphatase, and GGT. The total bilirubin level was 7.2 mg/dl and direct bilirubin level was 5.6 mg/dL.

Patient Data

Age: 7 weeks
Gender: Female

Abdominal ultrasound


Mild hepatosplenomegaly.

Normal liver echotexture of the liver except for hyperechogenic focus adjacent to the area of porta hepatis, representing a triangular cord sign.

A small gallbladder was demonstrated, with a maximal length measurement of 8 millimeters, corresponding to the atretic gallbladder.

Triangular cord sign

Annotated image

Increased echogenicity along the anterior wall of the portal vein consistent with positive triangular cord sign. The area of increased echogenicity measures 3.3 mm in maximum thickness on the transverse plane. 

Case Discussion

This case presents the classic sonographic findings of biliary atresia, including:

1. small gallbladder: gallbladder length less than 19 mm is suggestive for atretic gallbladder

2. triangular cord sign: increased echogenicity along the anterior wall of the portal vein, that represents the fibrous ductal remnant of the extrahepatic bile duct

In an infant presenting with conjugated hyperbilirubinemia, sonographic demonstration of small gallbladder and triangular cord sign makes the diagnosis of biliary atresia almost certain. 

The patient underwent a liver biopsy which showed extrahepatic biliary atresia, and portoenterostomy (Kasai procedure) was performed 4 days later.

Courtesy of Dr.Yair Halpern.

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