Calculate the ASGE probability of choledocholithiasis to select appropriate imaging and intervention.
Guidelines & Evidence
Clinical Details
Section 1
When to Use
When to Use
Initial evaluation of patients presenting with biliary symptoms (pain, abnormal LFTs) and suspected CBD stones
To select the optimal diagnostic modality (EUS vs. MRCP vs. immediate ERCP)
Pre-operative evaluation of patients undergoing laparoscopic cholecystectomy
Exclusion Criteria
Not for patients with acute ascending cholangitis — these patients are automatically high-risk and require prompt biliary drainage via ERCP regardless of bilirubin levels or duct diameter.
Section 2
Formula & Logic
Risk Predictors (ASGE 2019)
The 2019 update refined the previous 2010 criteria. High-risk predictors are now more strictly defined to reduce the rate of "unnecessary" diagnostic ERCP (which carry a 5–10% complication risk).
High Risk (> 50% probability)
CBD stone visualized on ultrasound or other imaging
Total bilirubin > 4 mg/dL AND dilated CBD on US (> 6 mm if GB in situ, > 8 mm post-chole)
Ascending cholangitis (technically "Very High Risk" but managed as High)
Intermediate Risk (10–50% probability)
Abnormal LFTs (AST, ALT, or Alk-Phos) and no other predictors
Age > 55 years
Dilated CBD on US without hyperbilirubinaemia
Low Risk (< 10% probability)
No biliary risk factors or LFT abnormalities identified
Section 3
Pearls/Pitfalls
Refining the Predictors
The most common pitfall in the 2010 guidelines was the "intermediate" category which was too broad. 2019 narrowed the high-risk criteria. Specifically, isolated hyperbilirubinaemia (without duct dilation) should now be managed with intermediate-modality imaging (EUS/MRCP) first.
EUS vs. MRCP
In the intermediate risk group, EUS has a higher sensitivity (approx. 95%) particularly for small stones (< 5mm) compared to MRCP (approx. 85%). If EUS is available, it is the preferred "confirmed-and-drain" strategy when combined with ERCP in a single session.
Clinical Pearls
Isolated ALT/AST elevation > 3x ULN can sometimes reflect transient CBD stone passage
Total Bilirubin 1.8–4 mg/dL combined with a dilated CBD is now considered "Intermediate," not "High"
Routine intraoperative cholangiogram (IOC) during cholecystectomy is an alternative to preoperative EUS for intermediate risk patients
Section 4
Next Steps
Recommended Action Pathways
01
High Risk: Proceed directly to ERCP or CBD exploration.
02
Intermediate Risk: Perform EUS or MRCP. Proceed to ERCP only if stones are confirmed.
03
Low Risk: Proceed to Cholecystectomy without further biliary imaging.
Complementary Scoring
Tokyo Guidelines for Cholangitis
Child-Pugh Score (if cirrhotic)
MELD Score (if cirrhotic)
Section 5
Evidence Appraisal
The 2019 Update
ASGE guideline on the role of endoscopy in the evaluation and management of choledocholithiasis.
ASGE Standards of Practice Committee et al. • Gastrointestinal Endoscopy. 2019;89(6):1075-1105.e15. The core updated evidence-based algorithm.
The American Society for Gastrointestinal Endoscopy (ASGE) develops these guidelines through a rigorous process of evidence synthesis. The 2019 update was driven by data showing that many "high-risk" patients under the 2010 rules (TB 1.8-4 + dilated CBD) actually had no stones on ERCP, leading to unnecessary risk and cost.
