Difference in microbes contaminating pancreatic necrosis in biliary and alcoholic pancreatitis

Conclusion. There are differences in the microbiology of infected pancreati c necrosis in alcoholic and biliary pancreatitis. One possible explanation may be different routes of contamination. Background. Infection is a severe complication in acute pancreatitis. Bacte ria are found in 40-70% of all patients suffering from necrotizing pancreat itis. We investigated whether there were any differences in microbes isolat ed from pancreatic necrosis in biliary and alcoholic pancreatitis. Methods. Microbiological tests were conducted on necrosis taken at the oper ation for pancreatitis with the etiology of (group A) alcoholic pancreatiti s (it = 47) and (group B) biliary pancreatitis (n = 23). Patients with simu ltaneous cholecystitis were excluded. The time from the first symptoms to t he operation or the extent of necrosis did not differ between the groups. Results. Microbes were isolated more often in the cultures from group B tha n group A (17/23 = 74% vs 15/47 = 32%, p = 0.001). The most common were Gra m-positive bacteria in group A and Gram-negative bacteria in group B. From the first week, from the onset of symptoms to the operation, Gram-negative bacteria were isolated significantly more often in the cultures from group B patients than from group A patients (8/10 = 80% vs 1/5 = 20%, p = 0.04). In multivariate analysis, we found that biliary pancreatitis was an indepen dent risk factor (adds ratio 5.5, 95% confidence interval [CI] 0.59-52.10) of contamination of necrosis with Grain-negative bacteria.