Background/Aims: This study assessed the significance of biliary stricture in symptomatic chronic pancreatitis patients requiring extracorporeal shock wave lithotripsy (ESWL) and endoscopic retrograde cholangiopancreatography (ERCP) to remove obstructing pancreatic calculi. Methods: A total of 97 patients underwent ESWL followed by ERCP to remove pancreatic calculi between October 2014 and October 2017 at Virginia Mason Medical Center. Significant biliary stricture (SBS) was defined as a stricture with upstream dilation on computed tomography scan or magnetic resonance cholangiopancreatography scans accompanied by cholestasis and/or cholangitis. SBS was initially managed by either a plastic stent or fully covered self-expandable metallic stent (fcSEMS). If the stricture did not resolve, the stent was replaced with either multiple plastic stents or another fcSEMS. Data were collected by retrospectively reviewing the medical records. Results: Biliary strictures were noted in approximately one-third of patients (34/97, 35%) undergoing ESWL for pancreatic calculi. Approximately one-third of the biliary strictures (11/34, 32%) were SBS. Pseudocysts were more frequently found in those with SBS (36% vs 8%, p=0.02), and all pseudocysts in the SBS group were located in the pancreatic head. The initial stricture resolution rates with fcSEMSs and plastic prostheses were 75% and 29%, respectively. The overall success rate for stricture resolution was 73% (8/11), and the recurrence rate after initial stricture resolution was 25% (2/8). Conclusions Although periductal fibrosis is the main mechanism underlying biliary stricture development in chronic pancreatitis, inflammation induced by obstructing pancreatic calculi, including pseudocysts, is an important contributing factor to SBS formation during the acute phase.

BACKGROUND/AIMS: Acute pancreatitis complicated by walled-off necrosis (WON) is associated with high morbidity and mortality, and if infected, typically necessitates intervention. Clinical outcomes of infected WON have been described as poorer than those of symptomatic sterile WON. With the evolution of minimally invasive therapy, we sought to compare outcomes of infected to symptomatic sterile WON. METHODS: We performed a retrospective cohort study examining patients who were undergoing dual-modality drainage as minimally invasive therapy for WON at a high-volume tertiary pancreatic center. The main outcome measures included mortality with a drain in place, length of hospital stay, admission to intensive care unit, and development of pancreatic fistulae. RESULTS: Of the 211 patients in our analysis, 98 had infected WON. The overall mortality rate was 2.4%. Patients with infected WON trended toward higher mortality although not statistically significant (4.1% vs 0.9%, p=0.19). Patients with infected WON had longer length of hospitalization (29.8 days vs 17.3 days, p<0.01), and developed more spontaneous pancreatic fistulae (23.5% vs 7.8%, p<0.01). Multivariate analysis showed that infected WON was associated with higher odds of spontaneous pancreatic fistula formation (odds ratio, 2.65; 95% confidence interval, 1.20 to 5.85). CONCLUSIONS: This study confirms that infected WON has worse outcomes than sterile WON but also demonstrates that WON, once considered a significant cause of death, can be treated with good outcomes using minimally invasive therapy.
Cause of Death ; Cohort Studies ; Drainage ; Hospitalization ; Humans ; Intensive Care Units ; Length of Stay ; Mortality ; Multivariate Analysis ; Necrosis ; Outcome Assessment (Health Care) ; Pancreatic Fistula ; Pancreatitis ; Pancreatitis, Acute Necrotizing ; Retrospective Studies