An Unusual Presentation of a Rare Clinical Entity - A Case Report of Spontaneous Common Bile Duct Perforation in an Adult

Abstract Spontaneous or non-traumatic perforation of the extrahepatic biliary system is a rare clinical phenomenon, with few cases reported since its first mention in medical literature by Freeland in 1882. Given the rarity, misdiagnosis is common with the diagnosis almost always made during urgent exploratory laparotomy. We describe a case of spontaneous common bile duct (CBD) perforation in an 83-year-old female with no associative underlying disease process identified. The patient presented with sudden onset abdominal pain with no identifiable trigger, with minimal past medical history. Examination was remarkable for findings of epigastric tenderness and guarding. Haematological investigation was remarkable only for hyperamylasaemia and leucocytosis. Pneumoperitoneum was ruled out and following contrast CT abdomen and pelvis a working diagnosis of mild pancreatitis was made. US Abdomen and MRCP found no evidence of cholelithiasis, with minimal biliary duct dilatation. The patient continued to deteriorate on the ward, with aspiration of new intrabdominal fluid collection raising suspicion of perforated viscus. Exploratory laparotomy revealed a 1-cm defect in the CBD with frank bile leak. A T-tube was placed in the common bile duct defect, with an abdominal robertson drain also inserted. No further bile leak was identified via Tubogram, with the patient successfully discharged following multidisciplinary rehabilitation in intensive care and the ward setting. Surgeons should seek out this uncommon diagnosis in patients with hyperamylasaemia and suspected cholelithiasis who do not conform to normal biliary/pancreatic disease progression patterns.