mNGS is popular in research and recently it has been used clinically to detect microbes in the blood or other secretion in infected patients for quicker ,broad and accurate detection of microbes. In ICU ,patients are critically ill and need quicker and accurate antibiotics use to stop the pathologic process. The purpose of this study was to determine whether the positive detection rate of pathogens in patients with sepsis by metagenomic full-targeted detection technology was higher than that in blood culture, and to determine whether the pathogens found in patients with sepsis by metagenomic full-targeted detection technology were important for clinical development. Anti-infective regimens can help.

Sepsis patients in ICU were took blood culture sample and blood sample for mNGS test (IDSeqTM Ultra, Combing with Metagenomics and Pathogen/AMR/VF Probe Enrichment). Clinicians use their knowledge and experience to decide antibiotics use with the guide of Culture results or mNGS results. Validation with digital droplet PCR assays when metagenomic full-targeted assays identify pathogens not identified in conventional blood cultures The difference between the positive rate of mNGS and the positive rate of blood culture were recorded. Patient were followed at least 28 days after enrollment or an outcome indicator. Possible scenarios for detecting clinical impact were detected. Etiology, biochemical indicators, immune function, infection indicator, secondary infection, SOFA score and length of stay，outcome were recorded.

Inclusion Criteria:

Age > 18years admit to ICU Meet the Sepsis 3.0 diagnostic criteria and suspected bloodstream infection, and the diagnosis of Sepsis ≤ 24 hours; Estimated ICU stay ≥ 24 hours; Informed consent;

Exclusion Criteria:

Severe organ dysfunction, expected death within 72 hours; Receive palliative care; Refuse to participate;

Patient with sepsis and suspected bloodstream infection