Biliary Stricture after Necrotizing Pancreatitis: An Underappreciated Challenge

OBJECTIVE Biliary stricture in necrotizing pancreatitis (NP) has not been systematically categorized; therefore, we sought to define the incidence and natural history of biliary stricture caused by NP. SUMMARY/BACKGROUND DATA Benign biliary stricture occurs secondary to bile duct injury, anastomotic narrowing, or chronic inflammation and fibrosis. The profound loco-regional inflammatory response of NP creates challenging biliary strictures. METHODS NP patients treated between 2005-2019 were reviewed. Biliary stricture was identified on cholangiography as narrowing of the extrahepatic biliary tree to < 75% of the diameter of the unaffected duct. Biliary stricture risk factors and outcomes were evaluated. RESULTS Among 743 NP patients, 64 died, 13 were lost to follow up; therefore, a total of 666 patients were included in the final cohort. Biliary stricture developed in 108 (16%) patients. Mean follow up was 3.5 ± 3.3 years. Median time from NP onset to biliary stricture diagnosis was 4.2 months (IQR, 1.8-10.9). Presentation was commonly clinical or biochemical jaundice, n = 30 (28%) each. Risk factors for stricture development were splanchnic vein thrombosis and pancreatic head parenchymal necrosis. Median time to stricture resolution was 6.0 months after onset (2.8-9.8). A mean of 3.3 ± 2.3 procedures were performed. Surgical intervention was required in 22 (20%) patients. Endoscopic treatment failed in 17% (17/99) of patients and was not associated with stricture length. Operative treatment of biliary stricture was more likely in patients with infected necrosis or NP disease duration ≥6 months. CONCLUSION Biliary stricture occurs frequently after necrotizing pancreatitis and is associated with splanchnic vein thrombosis and pancreatic head necrosis. Surgical correction was performed in 20%.