Infectious Complications of Acute Pancreatitis Is Associated with Peripheral Blood Phagocyte Functional Exhaustion

Infected pancreatic necrosis is one of the most severe complications of acute pancreatitis (AP). The development of secondary infection doubles the risk of death during the late stage of necrotizing pancreatitis. Phagocytes play a major role in AP pathogenesis, as well as in local and systemic complications of the disease.

We aimed to investigate the relationship between quantitative and functional indices of circulating phagocyte at the time of admission and onset of infectious complications in patients with AP afterward.

A post hoc analysis of 97 patients with AP was conducted. The metabolic state of peripheral blood neutrophils and monocytes was analyzed based on their phagocytic activity and generation of reactive oxygen species (ROS), which were determined by flow cytometry on admission. The clinical end point was marked by onset of infectious complications of AP.

On admission, baseline values and reactivity reserve of monocyte and neutrophil phagocytic activity in AP patients, who developed septic complications, were substantially decreased, whereas monocyte ROS generation was dramatically increased as compared to the group without infectious processes. ROC curve was obtained both for neutrophil and monocyte phagocytosis reactivity reserve expressed as modulation coefficient values and categorized as the risk factor of infectious complications, showing an area under curve of 0.95 (P < 0.0001) and 0.84 (P < 0.0001), respectively.

Early (at the time of admission) detection of quantitative and functional indices of circulating phagocytes can be useful for the prediction of septic complications in SAP patients.