Abstract
Background: Direct microscopic examination of bile for the presence of microlithiasis is often performed during the evaluation of patients with idiopathic pancreatitis. Bile sampled from the duodenum and/or the common bile duct may not represent gallbladder bile, and thus may be inadequate for the diagnosis of microlithiasis. Aim: We sought to determine the safety and efficacy of endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) of gallbladder bile in patients with idiopathic pancreatitis. Methods: Patients with idiopathic pancreatitis underwent EUS with a linear echoendoscope. After excluding potential causes of pancreatitis such as common bile duct stones or pancreatic lesions, the gallbladder was identified. The gallbladder lumen was entered using a 22-gauge FNA needle via the duodenal wall. Bile was aspirated and analyzed for the presence of cholesterol monohydrate crystal, calcium bilirubinate granules, calcium carbonate microspheroliths and mucin gel strands. Results: Three patients underwent EUS-guided FNA of gallbladder bile. Two of these patients developed bile peritonitis within one hour of the procedure prompting us to discontinue the study. One patient’s gallbladder bile contained microlithiasis. This patient had bile aspirated from the common bile duct via ERCP 3 weeks prior to EUS. However, analysis of that bile sample failed to show microlithiasis. Conclusion: Unfortunately, transduodenal EUS-guided FNA of gallbladder bile using a 22-gauge needle carries a significant risk of bile peritonitis.