Characteristics and risk factors for extrapancreatic infection in patients with moderate or severe acute pancreatitis.

Background: How to detect acute pancreatitis (AP) complicated with infection early and how to arrange the treatment time are still the main problems in the world. There are few reports on the potential relationship between extrapancreatic infections and AP. The purpose of this article was to investigate the characteristics, influencing factors and prognosis of extrapancreatic infection in AP patients with modified Marshall score ≥2 on admission. Materials and methods: We retrospectively analyzed AP admitted to emergency intensive care unit of Ruijin hospital within 72 h of onset from September 2019 to December 2021. In addition to the patients' baseline data, sites of infection and microorganisms outside the pancreas were collected. Microbial cultures were used to identify infections of the respiratory tract, blood, abdominal cavity, biliary tract, urinary tract and clostridium difficile in feces. Results: 144 patients with AP were included, of which extrapancreatic infection accounted for 40.28%. C-reactive protein, procalcitonin, blood urea nitrogen, serum creatinine, oxygenation index, modified Marshall score, BISAP score and APACHE II score were significantly increased in the extrapancreatic infection group. The risk factors of extrapancreatic infection included blood urea nitrogen, Modified Marshall score and duration of mechanical ventilation. The positive rates of pathogenic bacteria in sputum culture, blood culture, ascites culture and bile culture were significantly higher than those in the 1-3 days after admission. The infection begins to worsen as early as 4-7 days after the onset of symptoms. Extrapancreatic infection is associated with pancreatic necrosis, the rate of laparotomy, length of hospital stay and in-hospital mortality. Conclusion: Our research has confirmed the need to prevent and monitor extrapancreatic infection in the early stage.