Natural Course of Common Bile Duct Microlithiasis.

Background: Common bile duct microlithiasis (CBDM) with a diameter of ≤ 3 mm can pass spontaneously without causing any symptoms, but in some cases, it can also cause severe cholangitis and pancreatitis. The optimal strategy for managing CBDM is yet to be determined.

Methods: Data of 154 patients with CBDM were collected and divided into two groups: with endoscopic retrograde cholangiopancreatography (with ERCP, n = 82) and without ERCP (n = 72). Clinical outcomes, including the incidence of unfavorable outcomes (UOs), such as cholangitis and pancreatitis, were observed and compared between the two groups.

Results: The incidence of UOs was significantly lower in the ERCP group than in the without ERCP group (3.7% vs. 23.6%, respectively, p < 0.001). Moreover, the total number of readmissions was also lower in the ERCP group than in the without ERCP group (p < 0.001). A multivariate analysis adjusted for age, sex, and the American Society of Anesthesiologists (ASA) class revealed that endoscopic sphincterotomy (EST) and cholecystectomy were associated with a lower risk of UOs.

Conclusion: The high rate of UOs in CBDM patients without ERCP suggests that its natural clinical course may not be as favorable as previously suggested. This finding implies that efforts should be made to clear the bile ducts.