Mechanisms of sepsis in acute pancreatitis in opossums

Purpose To study the incidence and pathways of colonization of the pancreas by specific bacteria in a model of necrotizing pancreatitis. Methods Bacteremia and splanchnic organ colonization were studied in the early course of necrotizing pancreatitis following common biliopancreatic duct ligation (BPDL) of the opossum. Nonoperated animals served as controls. Intestinal lymph nodes, liver, spleen, and pancreas were cultured following bacteremia or sacrifice. Results In opossums with sterile bile, bacteria were recovered from 28.6% of blood cultures after BPDL (n = 10) and from 12.0% in controls (n = 10, P<0.05). Animals that underwent BPDL revealed enteric microorganisms in intestinal lymph nodes (6), liver (3), spleen (4), and pancreas (4). Ten animals carried Salmonella within their bile (5 controls, 5 BPDL animals). Following BPDL, they developed rapid bacteremia and colonization of organs, pancreatic ductal rupture, and extravasation of bacteria and bile into the interstitium. Conclusion There are two possible mechanisms for the development of bacterial colonization in opossum pancreatitis: bacterial translocation of enteric organisms from gut lumen to mesenteric lymph nodes and subsequent hematogenous dissémination and transductal infestation from the biliary tract.