This study adopted a case-control study method to explore a reagent-free, highly sensitive, and frequently screened blood fluorescence metabolite analyzer for sepsis, which can detect the emergence of inflammatory free radicals before organ damage and shorten the diagnosis time of sepsis.

Currently, clinical practice lacks an effective screening method for early detection and prediction of sepsis. This gap hinders timely differential diagnosis, leading to severe shock and increased mortality rates. Although the qSOFA score is highly specific, it is not devoid of false negatives. Typically, by the time sepsis is confirmed using the qSOFA (≥ 2) and SOFA (≥ 2) scores as gold standards, the patient may already be suffering from organ damage, thus escalating the risk of death. Early-stage septic patients exhibit a surge in inflammatory free radicals, altering the optical characteristics of their blood compared to that of healthy individuals. Based on this, we hypothesize that a blood fluorometer could detect these early changes in septic patients, enabling rapid and accurate diagnosis to mitigate mortality rates. This study will conduct a case-control investigation, collecting blood from both admitted and discharged patients, with the aim of developing a reagent-free, highly sensitive blood fluorescence metabolite analyzer. This device will be capable of frequent sepsis screenings, detecting inflammatory free radicals before organ damage occurs, thereby reducing the time to sepsis diagnosis.

Inclusion Criteria:

1. Healthy control group: Individuals who are physically healthy with no underlying diseases and have not been hospitalized within the past two years. Recruitment for healthy volunteers will be conducted through notices and online media.
2. Sepsis Experimental Group: Patients with confirmed infections, having qSOFA ≥ 2 and SOFA ≥ 2, will be screened and confirmed by a physician to meet the inclusion criteria.
3. Non-septic Severe Control Group: Patients with suspected or confirmed infections, having a SOFA score of 1, will be screened and confirmed by a physician to meet the inclusion criteria.

Exclusion Criteria: minors, pregnant, individuals with mental illnesses, and other vulnerable groups.

1. Healthy control group: Individuals who are physically healthy with no underlying diseases and have not been hospitalized within the past two years. Recruitment for healthy volunteers will be conducted through notices and online media.
2. Sepsis Experimental Groups: Inpatients with confirmed infections, having qSOFA ≥ 2 and SOFA ≥ 2, will be screened and confirmed by a physician to meet the inclusion criteria. The experimental group in this study was divided into two subgroups. One was the group of sepsis patients who used vasopressors, and the other was the group of sepsis patients who did not use vasopressors.
3. Non-septic Severe Control Group: Inpatients with suspected or confirmed infections, having a SOFA score of 1, will be screened and confirmed by a physician to meet the inclusion criteria.