The diagnostic yield of endoscopic ultrasonography in patients with suspected Choledocholithiasis

Background: Choledocholithiasis is the most common cause of biliary obstruction, which occurs in 10 – 20% of patients with cholelithiasis. Management of suspected choledocholithiasis requires confirmation of stones in the common bile duct (CBD). The diagnosis is based on clinical signs and symptoms, laboratory- and imaging examination findings. Likelihood of CBD stones can be prognosticated by the presence of various clinical predictors, however the sensitivity and specificity of these factors is moderate. Endoscopic ultrasonography (EUS) has been shown to be a non-invasive precise test for the detection of CBD stones. Aim: To assess the diagnostic yield of EUS in patients with suspected choledocholithiasis in a high-volume center during the period of one-month. Methods: Prospective study of patients with cholelithiasis and clinical symptoms or abnormal liver function tests who underwent transabdominal ultrasonography (USG) that could not detect CBD stones (except in one case) were categorized and divided into an intermediate- and high likelihood groups according to the clinical predictors (i.e. serum bilirubin, age, CBD diameter) defined by the American Society of Gastrointestinal Endoscopy (ASGE) guidelines and referred for radial EUS. Results: Total of 26 patients, 14 females and 12 males (average age of 40.8 ± 17.3 and 51.1 ± 14.9, respectively) were assessed. CBD stones were detected by EUS overall in 17 (65.4%) patients: 61.5% of patients (8/13) in the intermediate likelihood- and 69.2% of patients (9/13) in the high likelihood-group. The size and the number of detected CBD stones in all patients were confirmed by the followed therapeutic endoscopic retrograde cholangio-pancreatography (ERCP) except in one case where a preampullary calcific stenosis was described as a calculus during the EUS. Conclusion: EUS is a highly sensitive and accurate diagnostic tool for the detection and evaluation of CBD stones also in patients with previous negative USG findings. Further study is needed to assess the potential correlation of clinical data with EUS findings in the detection of suspected choledocholithiasis.