Ultrasound Findings of Bile Duct Involvement in Pediatric Langerhans Cell Histiocytosis

Objective This study aimed to analyze the ultrasound findings of bile duct involvement in pediatric Langerhans cell histiocytosis (LCH). Methods We retrospectively analyzed 42 patients diagnosed with pediatric LCH by pathology at our hospital from December 2016 to December 2023. All patients had comprehensive clinical data and ultrasound findings indicating biliary abnormalities. This study analyzed intrahepatic and extrahepatic bile duct dilation, the extent of bile duct wall thickening, and surrounding abnormal echoes. Results Among the 42 children, ultrasonography showed intrahepatic and extrahepatic bile duct dilation in 27 cases (64%), bile duct wall thickening in 21 cases (50%), hypoechoic areas along the intrahepatic bile ducts in 16 cases (38%), and thickening of the Glisson's capsule with decreased echogenicity around the bile ducts in 8 cases (19%). Conclusion Ultrasonography revealing varying degrees of bile duct dilatation or stenosis, thickened bile duct walls, and abnormal echo patterns along the bile duct in the liver in pediatric patients with cholangitis should raise suspicion for LCH.