Enteric bacterial loads are associated with interleukin-6 levels in systemic inflammatory response syndrome patients

Background Loss of intestinal integrity is a critical contributor to excessive inflammation following severe trauma or major surgery. In the case of enterocyte damage, intestinal fatty acid-binding protein (IFABP) is released into the extracellular space. Excessive production of interleukin (IL)-6 can induce systemic inflammatory response syndrome (SIRS). However, the correlation of IL-6 with gut barrier failure and bacterial translocation in critically ill patients has not been well characterized. Purposes To define the relationship between enteric bacterial loads and IL-6 levels in patients with SIRS. Methods Variables related to prognosis and treatment were measured in 85 patients with SIRS upon admission to the emergency room. IL-6 and IFABP were measured using an enzyme-linked immunosorbent assay. Enteric bacterial loads in blood were measured through quantitative real-time polymerase chain reaction with primers specific for enteric bacteria. Results Multivariate analysis revealed a positive correlation between enteric bacterial loads and IL-6 levels in blood. Elevated IFABP concentration was associated with low blood pressure, high respiration rate, hyperglycemia, and high Sequential Organ Failure Assessment score. Elevated C-reactive protein concentrations were associated with higher soluble CD14 levels in blood. Conclusion Enterocyte damage is associated with hypotension and tachypnia in patients with SIRS. Gut function failure may permit enteric bacteria to enter the blood, thereby elevating IL-6 levels and inducing a systemic inflammatory response, resulting in multiple organ failure.