Background: Patients often recover from an episode of acute pancreatitis with conservative therapy and without an identified cause. The options include proceeding with ERCP to identify and treat an occult common bile duct stone or performing the procedure only after a second episode of idiopathic pancreatitis occurs.
Methods: Decision analysis (SMLTREE software) was used to determine incremental cost-utility. Variables were estimated from a search of the literature, a utility analysis involving health professionals familiar with the question, and a retrospective review of hospital charts and costs.
Results: This model estimates an incremental utility gain for the prompt ERCP approach of 1.0 quality-adjusted life weeks per patient at an incremental cost of $245 (Canadian). This yields a cost-utility ratio of $12,740 (Canadian) per quality-adjusted life year. The result was highly sensitive to the probability of finding an occult common bile duct stone.
Conclusion: Routine ERCP is of marginal overall benefit, but is of more substantial benefit and is more cost-effective in a subgroup of patients with a greater probability of having an occult common duct stone.