Sepsis ICU Gut Microbiome Analysis

Sepsis is a life-threatening condition in which the body's response to an infection damages its own organs. This study aims to understand how the bacteria living in the gut change during sepsis and whether patterns of gut bacteria and chemicals found in stool can help identify patients at greater risk of death or poor recovery. This observational study plans to enroll approximately 180 adults with sepsis receiving care in the intensive care unit (ICU) at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. All participants will receive usual medical care. The study will not assign experimental treatments or change treatment decisions. Researchers will collect stool samples or, when stool is unavailable and sampling is safe, rectal swabs. Samples will be collected within the first 48 hours of the study, on days 3-5, on day 7, and near ICU discharge when feasible. Researchers will examine the types and amounts of gut bacteria. Samples from a selected group of participants will also be tested for chemicals related to metabolism. Information about illness severity, medicines, nutrition, and organ support will be collected from medical records. Participants will be followed for 90 days, using medical records and telephone follow-up. The main clinical outcome is death from any cause within 28 days. Other outcomes include death and unplanned hospital readmission within 90 days. Researchers will assess whether gut bacterial patterns add useful information to routine clinical assessments and compare findings with available data from other sepsis studies.