The role of extra-pancreatic infections in the prediction of severity and local complications in acute pancreatitis

Background: The aim of our study was to determine the risk factors for extrapancreatic infection (EPI) occurrence and its predictive power for assessing severity and local complications in acute pancreatitis including infected pancreatic necrosis (IPN).

Methods: Clinical data of 176 AP patients prospectively enrolled were analysed. EPI analysed were bacteraemia, lung infection, urinary tract infection and catheter line infection. Risk factors analysed were: Leukocyte count, C-reactive protein, liver function test, serum calcium, serum glucose, Blood urea nitrogen, mean arterial pressure at admission, total parenteral nutrition (TPN), enteral nutrition, hypotension, respiratory, cardiovascular and renal failure at admission, persistent systemic inflammatory response (SIRS) and intrapancreatic necrosis. Severity outcomes assessed were defined according to the Atlanta Criteria definition for acute pancreatitis. The predictive accuracy of EPI for morbidity and mortality was measured using area-under-the-curve (AUC) receiver-operating characteristics.

Results: Forty-four cases of EPI were found (25%). TPN (OR:9.2 CI95%: 3.3-25.7), APACHE-II>8 (OR:6.2 CI95%:2.48-15.54) and persistent SIRS (OR:2.9 CI95%: 1.1-7.8), were risk factors related with EPI. Bacteraemia, when compared with others EPI, showed the best accuracy in predicting significantly persistent organ failure (AUC:0.76, IC95%:0.64-0.88), ICU admission (AUC:0.80 IC95%:0.65-0.94), and death (AUC:0.73 CI95%:0.54-0.91); and for local complications including IPN (AUC:0.72 CI95%:0.53-0.92) as well. Besides, it was also needed for an interventional procedure against necrosis (AUC:0.74 IC95%: 0.57-0.91). When bacteraemia and IPN occurs, bacteraemia preceded infected necrosis in all cases. On multivariate analysis, risk factor for IPN were lung infection (OR:6.25 CI95%1.1-35.7 p = 0.039) and TPN (OR:22.0CI95%:2.4-205.8, p = 0.007), and for mortality were persistent SIRS at first week (OR: 22.9 CI95%: 2.6-203.7, p = 0.005) and Lung infection (OR: 9.7 CI95%: 1.7-53.8).

Conclusion: In our study, EPI, played a role in predicting the severity and local complications in acute pancreatitis.