Infected Necrotizing Pancreatitis: Evolving Interventional Strategies From Minimally Invasive Surgery to Endoscopic Therapy—Evidence Mounts, But One Size Does Not Fit All

Abstract

Necrotizing pancreatitis occurs in ≤10%–20% of all patients with acute pancreatitis and portends a severe course of the disease.1 Pancreatic and peripancreatic necroses may strike a dual blow: (1) by causing sterile systemic inflammatory response syndrome and (2) by providing a fertile ground for microorganisms, resulting in infected necrosis and sepsis.1 Sterile systemic inflammatory response syndrome is due to the release of damage-associated molecular patterns from necrotic cells that lead to immune activation and release of cytokines.2 Systemic inflammation, when severe, may lead to organ failure, which is the cause of most mortality in patients with acute pancreatitis. Infection of necrotic fluid collections is an ominous development during the course of necrotizing pancreatitis, and is an independent determinant of survival. Infection may develop any time during the disease process, but mostly occurs beyond the second week of illness.1 The revised Atlanta classification defines necrotic collections of <4 weeks duration as acute necrotic collections.3 As part of the body’s reparative processes, the necrotic areas gradually become localized and walled off, known as “walled off necrosis.” The distinction between acute necrotic collections and walled off necrosis has major implications for the treatment of patients with infected necrosis. There is a correlation between the extent and infection of necrosis, and organ failure, which may either precede (mostly) or follow infected necrosis.4 The outcome of patients with infected necrosis is worse in those with than in those without organ failure.5