Bacterial translocation during acute pancreatitis in rats

Abstract

Objective: To see if bile-induced pancreatitis could cause bacterial translocation to mesenteric lymph nodes, and therefore pancreatic necrosis, in rats.

Design: Controlled experiment.

Material: 18 Male Wistar rats.

Interventions: Pancreatitis was induced in the experimental group (n = 12) by infusion of 0.2 ml of a solution containing 4 mumol (20 mumol/ml) sodium taurodeoxycholate into the pancreatic duct over one minute. The controls had sham operations (no infusion). Two days later repeat laparotomy was done on all surviving animals and samples taken for microbiological analysis. All animals were weighed at the beginning and end of the experiment.

Results: Bacteria were isolated from the mesenteric lymph nodes in all survivors in the experimental group (9/12), and from the pancreas in all but one. Blood and peritoneal fluid were colonised in 5 and 7 rats, respectively. Escherichia coli was the most common organism isolated. Positive anaerobic cultures were obtained from mesenteric lymph nodes in 5, and from the pancreas in one. Rats with pancreatitis developed overgrowth of both aerobic and anaerobic bacteria in the caecum and the ileum, but on light microscopic examination the proximal and distal intestinal mucosa did not differ between control and experimental rats. Bacterial translocation increased as the condition of the animals worsened.

Conclusion: Acute pancreatitis in rats causes systemic bacterial colonisation, probably as a result of bacterial translocation, which may therefore be a mechanism of pancreatic infection.