Evaluation of biomarkers from peritoneal fluid as predictors of severity for abdominal sepsis patients following emergency laparotomy

Abstract

Background: An intra-abdominal infection is regarded as the second most course of sepsis, and results in either localized or diffused inflammation of the peritoneum. The main treatment of abdominal sepsis is emergency laparotomy for source control. However, surgical trauma also causes inflammation and patients may become susceptible to postoperative complications. Therefore, it is necessary to identify biomarkers that can be used to distinguish sepsis from abdominal infection. Herein, the aim of this study was to investigate whether cytokines in abdominal cavity predict septic complications and their ability to indicate severity of illness following emergency laparotomy. Methods: We prospectively observed fifty-eighty patients with abdominal infection admitted to the intensive care unit (ICU) after emergency open abdominal surgery. SEPSIS-3 criteria were used for the diagnosis of sepsis or septic shock group. Blood samples and peritoneal fluid were drawn within eight hours of admission after surgery, clinical data were collected. Concentrations of cytokines both from serum and abdominal cavity were measured by using the LEGENDplexTM ®technique based on the flow cytometer. Results: We found significant elevations in peritoneal concentrations of IL-1β, IL-6, TNF-α,IL-17 ,IL-2 in the sepsis or septic shock patients compared with non-sepsis group after surgery. Positive correlations between these peritoneal cytokines with APACHE II scores, especially IL-6 had the highest correlation coefficient of 0.833. At meantime, IL-10 in the blood, chemokines of MCP-1 and IL-8 both in blood and peritoneum were extremely high in abdominal sepsis and septic shock patients, and also positive correlated with disease severity. Conclusions: This study suggests that cytokine storm occurred in abdominal cavity after emergency laparotomy which may be a main mechanism leading to sepsis. It may be useful to conduct IL-1β, IL-6, TNF-α,IL-17 ,IL-2 ,MCP-1 and IL-8 from the peritoneal fluid, combined with serum IL-10, MCP-1 and IL-8, into a cytokine panel, which may be valuable for assessing severity of sepsis and predicting mortality for abdominal infection after emergency laparotomy.