Biliary atresia with ectopic thyroid in the porta hepatis: a case report and literature review

Background: Ectopic thyroid is a rare disease, with ectopic thyroid in the porta hepatis being extremely rare. We present a rare case involving an infant with biliary atresia (BA) wherein ectopic thyroid tissue was incidentally discovered in the porta hepatis after the Kasai operation.

Case description: A 2-month-old boy initially presented with jaundice, manifesting as yellow skin and sclera, on the first day following birth. After receiving treatment at a local healthcare facility, jaundice partially subsided, but the color of his stool became lighter 15 days before admission to Tianjin Children's Hospital. Upon B-ultrasound examination at our outpatient clinic, the patient showed bilateral oblique hernia, bilateral testicular hydrocele, and umbilical hernia, and he was admitted to the Department of Gastroenterology at Tianjin Children's Hospital for further treatment of unexplained jaundice. Laparotomy was performed after a comprehensive evaluation, during which we observed the gallbladder to be small and poorly developed. Cholangiography was then performed, revealing visualization of the gallbladder and common bile duct but not the common hepatic duct or right and left hepatic ducts. Intraoperative frozen section examination of wedge-shaped liver tissue indicated findings consistent with extrahepatic biliary obstruction. The Kasai operation was subsequently performed, and an examination of the gallbladder and a fibrous plaque from the porta hepatis after the operation revealed the presence of ectopic thyroid tissues.

Conclusions: Ectopic thyroid in the porta hepatis is extremely rare. We reviewed literature from 1960 to 2022 and identified six relevant case reports of ectopic thyroid in the porta hepatis. To our knowledge, this report constitutes the first report of BA complicated by ectopic thyroid in the porta hepatis.