This observational cohort study aims to compare clinical outcomes and inflammatory responses between patients with viral sepsis, specifically COVID-19-associated sepsis, and those with bacterial sepsis. Conducted at Sichuan Provincial People's Hospital, the study will retrospectively analyze data from ICU patients admitted between July 2021 and December 2023. The primary objective is to identify reliable biomarkers and diagnostic methods to improve patient outcomes through personalized diagnostic and therapeutic strategies.

Sepsis, a major cause of morbidity and mortality in ICU patients, has garnered increased attention during the COVID-19 pandemic due to the high mortality rates associated with viral sepsis. This study seeks to elucidate the differences in clinical outcomes, inflammatory responses, and treatment strategies between bacterial and viral sepsis. By leveraging a comprehensive dataset of ICU patients diagnosed with sepsis at Sichuan Provincial People's Hospital, the study will retrospectively compare the two sepsis types.

A total of 267 patients diagnosed according to Sepsis 3.0 criteria, including 105 with bacterial sepsis and 162 with viral sepsis (COVID-19 confirmed via RT-PCR), will be included. Key clinical parameters such as mortality rate, length of ICU stay, SOFA scores, and the need for life support measures (mechanical ventilation, CRRT, ECMO) will be analyzed. Additionally, the study will examine cytokine profiles and other inflammatory markers to identify significant differences between the two groups.

The study will utilize advanced statistical methods, including Kaplan-Meier survival analysis, multinomial logistic regression, and ROC curve analysis, to evaluate the predictive power of various biomarkers. The findings are expected to highlight critical factors contributing to the higher mortality observed in viral sepsis and inform the development of targeted treatment strategies. The ultimate goal is to improve diagnostic accuracy and patient outcomes through personalized approaches tailored to the type of sepsis.

Key objectives include understanding the distinct inflammatory responses in bacterial and viral sepsis and identifying reliable biomarkers for differentiation. The study will also evaluate the impact of different treatment regimens, particularly antibiotic use, on clinical outcomes. Insights gained from this research will contribute to the broader understanding of sepsis management and guide future clinical practice and research.

Inclusion Criteria:

1. Patients diagnosed with sepsis according to Sepsis 3.0 criteria.
2. Patients with confirmed bacterial sepsis based on positive bacterial cultures.
3. Patients with confirmed viral sepsis, specifically COVID-19, diagnosed via RT-PCR for SARS-CoV-2 for viral group and negative for bacterial group.
4. Patients aged 18 years and older.
5. Patients admitted to the ICU during the study period.

Exclusion Criteria:

1. Patients with mixed bacterial and viral infections.
2. Patients with sepsis not meeting the Sepsis 3.0 criteria.
3. Patients who received immunomodulatory therapies other than standard treatments (e.g., investigational drugs).
4. Pregnant or breastfeeding women.

Patients admitted to the ICU of Sichuan Provincial People's Hospital from July 2021 to December 2023 diagnosed with sepsis according to Sepsis 3.0 criteria.

At this stage, the decision on whether to make individual participant data (IPD) available to other researchers has not been finalized. Considerations include ethical and privacy concerns, institutional policies, and the potential benefit to the scientific community. If data sharing is implemented in the future, it will comply with relevant regulations and guidelines, ensuring the privacy and confidentiality of the participants. Researchers interested in accessing the IPD may contact the principal investigator for further information and potential collaboration opportunities.