In a retrospective tertiary-centre cohort of 404 patients with common bile-duct stones, 113, or 28%, had no stone at EUS or ERCP and were classified as spontaneous passage. Younger age, smaller and single stones predicted passage. Post-ERCP pancreatitis occurred in 16.5% versus 7.6%, supporting pre-procedure clearance confirmation but not yet defining the best triage pathway.
Key findings
- Spontaneous passage occurred in 113 of 404 patients, 28%. Passage was less likely per ten-year age increase, RR 0.88 (95% CI 0.81-0.96), and per 1 mm larger stone, RR 0.78 (0.71-0.85), but more likely with a single stone, RR 1.64 (1.04-2.61). Post-ERCP pancreatitis occurred in 16.5% versus 7.6%, adjusted RR 2.48 (1.25-4.92).
Why this matters globally
Combining age, stone number and size with non-invasive imaging or EUS confirmation before ERCP may reduce non-beneficial procedures, with broad relevance to endoscopy safety and quality.
Thai researcher contribution
The identified clinical, epidemiological and analytical authors are affiliated with Chiang Mai University, making this directly relevant evidence from a Thai tertiary referral setting.
Limitations to consider
This was a retrospective single-centre study. Stone absence may reflect true passage or initial diagnostic error, patients proceeding to ERCP may differ through residual confounding, and association with pancreatitis does not prove that stone passage itself caused the complication.