Spontaneous retroperitoneal biloma in a patient with choledocholithiasis: Presentation of case

Introduction and importance: Spontaneous perforation of the biliary tree, resulting in retroperitoneal biloma in adults is an extremely rare condition, and may unfold to a potentially fatal outcome, particularly when the diagnosis and definitive treatment are delayed. Case presentation: We report a case of a 69-year-old male who presented to the emergency room with abdominal pain, localized to the right quadrants, associated with jaundice and dark-coloured urine. Abdominal imaging including CT scan, ultrasound and magnetic resonance cholangiopancreatography (MRCP) revealed a retroperitoneal fluid collection, a distended gallbladder with wall thickening and lithiasis, as well as a dilated common bile duct (CBD) with choledocholithiasis. The analysis of the retroperitoneal fluid obtained by CTguided percutaneous drainage was consistent with biloma. A combined approach of biloma percutaneous drainage and endoscopic retrograde cholangiopancreatography (ERCP)-guided stent placement in the CBD with biliary stones removal was successful in the management of this patient, despite the fact that the perforation site could not be detected. Clinical discussion: The diagnosis of biloma is based mainly on clinical presentation and abdominal imaging. If urgent surgical intervention is not indicated, pressure necrosis and perforation of the biliary tree may be avoided by timely percutaneous aspiration of the biloma and ERCP to remove the impacted stones in the biliary tree. Conclusion: Biloma should be considered in the differential diagnosis of a patient presenting with right upper quadrant or epigastric pain and an intra-abdominal collection on imaging. Efforts should be made in order to offer a prompt diagnosis and treatment to the patient.