Segmental Cholangiectasia of the Intrahepatic Bile Duct: A Case Report.

Introduction: Segmental cholangiectasia is a rare cause of focal intrahepatic bile duct dilatation that can mimic congenital, inflammatory, or neoplastic conditions, posing diagnostic challenges. Case Presentation: We describe a 58-year-old man with a longstanding cystic lesion in hepatic segment 8 who developed multiple cholangitic episodes. Despite the exclusion of infectious, autoimmune, and overt neoplastic disease, an elevated carbohydrate antigen 19-9 (CA 19-9) raised concern for intraductal papillary neoplasm of the bile duct and prompted anterior hepatic sectorectomy. Histopathology confirmed segmental cholangiectasia, showing ductal dilatation, bile stasis, cholesterol clefts, fibrosis, and mixed inflammation, without evidence of malignancy or IgG4-related disease. Discussion and Conclusion: Segmental cholangiectasia is a benign yet clinically significant entity that can mimic biliary tumors and prompt major surgery. This case, involving hepatic segment 8, expands the known anatomical spectrum and underscores the importance of multidisciplinary evaluation. Awareness of this condition may prevent misdiagnosis and guide appropriate management, while further studies are needed to better characterize its presentation in Western populations.