Clinical Characteristics and ERCP Treatment Outcomes of Two Types of Common Bile Duct Stones: A Ten-Year Experience

Common bile duct (CBD) stones are a common condition with high recurrence rates of stone and cholangitis. However, whether stone type influences recurrence remains unclear.

We retrospectively analyzed 190 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for CBD stones between January 2014 and December 2023. Patients were categorized into two groups: brown pigment stone (n = 127) and black pigment stone (n = 63). Clinical characteristics were compared and recurrence risk factors were analyzed. This study was approved by the Institutional Review Board of Peking University Third Hospital (Approval No. M2024869) and conducted in accordance with the Declaration of Helsinki (2013 revision).

Baseline characteristics were similar between groups, except the brown pigment group had higher rates of prior ERCP (33.1% vs. 17.5%), larger CBD diameter (15 mm vs. 12 mm), and more multiple stones (69.3% vs. 49.2%) (all p < 0.05). Recurrence of CBD stones (35.4% vs. 9.5%) and cholangitis (21.3% vs. 4.8%) was significantly higher in the brown pigment group (p < 0.05), with shorter median stone-free survival (67.0 vs. 82.0 months) and cholangitis-free survival (70.0 vs. 82.0 months). Multivariate analysis identified brown pigment stones (HR = 3.162, 95% CI: 1.337-7.482, p = 0.009) and prior ERCP (HR = 3.254, 95% CI: 1.798-5.888, p < 0.001) as independent risk factors for stone recurrence, while stone diameter ≤ 10 mm was protective (HR = 0.412, 95% CI: 0.220-0.773, p = 0.006). Brown pigment stones (HR = 3.434, 95% CI: 1.026-11.489, p = 0.045) and prior ERCP (HR = 2.398, 95% CI: 1.111-5.173, p = 0.026) also independently predicted cholangitis recurrence.

Brown pigment stones carry higher risks of stone and cholangitis recurrence, and ERCP may not be the preferred treatment.