EUS accurately predicts the need for therapeutic ERCP in patients with a low probability of biliary obstruction.

BACKGROUND: Because of its inherent risks, ERCP should only be performed for purposes of treatment. EUS and MRCP have emerged as diagnostic alternatives before therapeutic ERCP.

OBJECTIVE: Our purpose was to test the accuracy of EUS in predicting the need for therapeutic ERCP in low-risk patients.

DESIGN: Prospective, unblinded, single-center study.

SETTING: Academic center of the University of Witten/Herdecke.

PATIENTS: Fifty patients with clinical, laboratory, or transabdominal US findings suggestive of biliary obstruction were included.

INTERVENTIONS: After clinical assessment and US, all patients underwent EUS. If EUS was conclusive, either ERCP with sphincterotomy (EST) was performed or the patients were followed up for 1 year. If EUS was inconclusive, MRCP was performed, followed by ERCP or a 1-year follow-up. After each diagnostic step, the examiner decided whether any biliary conditon was present and whether therapeutic ERCP was necessary. The decicions were compared with the results of ERCP with EST or the outcome after the 1-year follow-up.

MAIN OUTCOME MEASUREMENTS: Accuracy of EUS in predicting the need for therapeutic ERCP.

RESULTS: Nine patients had ERCP with EST. The final assessment classified 2 of these interventions as having been unnecessary. EUS was conclusive in 49 cases. After EUS, the accuracy of the decision on the presence of a biliary condition increased from 82% to 96% and on the need for therapeutic ERCP from 86% to 96%.

LIMITATION: Single-center experience.

CONCLUSION: EUS accurately predicts the need for therapeutic ERCP in patients at low risk for biliary obstruction.