Granulomatous cholangitis mimicking hilar cholangiocarcinoma: a case report

BACKGROUND: Hilar biliary stricture caused by isolated fungal infections in immunocompetent patients are considered to be extremely rare and difficult to the diagnose from the outset. CASE PRESENTATION: We report a unique case of granulomatous cholangitis based on isolated biliary fungal infection manifesting as obstructive jaundice and mimicking hilar cholangiocarcinoma in an immunocompetent woman. A 67-year-old Japanese woman was referred to our hospital for obstructive jaundice. She had been followed up for hypochondroplasia by the referring physician. Her total bilirubin level was 5.4 mg/dL. Viral hepatitis screening was found to be negative, and serum IgG4 was within normal limits; however, her CA19-9 level was high. Abdominal computed tomography revealed dilatation of the intrahepatic bile ducts. Abdominal echogram detected a solid mass in the hilar bile duct. Her magnetic resonance cholangiopancreatography has also revealed an abrupt stenosis of the primary biliary confluence with upstream dilatation of the intrahepatic bile ducts. Endoscopic nasobiliary drainage was then performed to improve the obstructive jaundice. Although biliary cytology did not reveal malignant findings, the bile duct in the hilum showed severe stenosis, and hilar cholangiocarcinoma could not be completely excluded. The patient had a developmental disorder based on chondrodystrophy. To avoid excessive surgical stress, such as hepatic lobectomy, we performed resection of the extrahepatic bile duct and Roux-en-Y hepaticojejunostomy reconstruction. Intraoperative frozen sections of the resection margins were determined to be negative for tumor. The resected specimen showed multiple strictures inside the common bile duct, numerous calculi in the lumen, and little free space. The final pathological diagnosis was granulomatous cholangitis due to fungal infection. The patient’s postoperative course was deemed uneventful. She was discharged from our hospital 23 days after surgery without antifungal treatment. CONCLUSIONS: For a unique case of granulomatous cholangitis based on isolated biliary fungal infection mimicking hilar cholangiocarcinoma, we were able to avoid excessive invasion and performed appropriate surgical management.