Early identification of a patient with infection who may develop sepsis is of utmost importance. Unfortunately, this remains elusive because no single clinical measure or test can reflect complex pathophysiological changes in patients with sepsis. However, multiple clinical and laboratory parameters indicate impending sepsis and organ dysfunction. Screening tools using these parameters can help identify the condition, such as SIRS, quick SOFA (qSOFA), National Early Warning Score (NEWS), or Modified Early Warning Score (MEWS). The 2016 SCCM/ESICM task force recommended using qSOFA, while the 2021 Surviving Sepsis Campaign strongly recommended against its use compared with SIRS, NEWS, or MEWS as a single screening tool for sepsis or septic shock. We hypothesised that qSOFA has greater prognostic accuracy than SIRS and EWS (NEWS/NEWS2/MEWS).

Over the past decade, medical advances in sepsis continued to focus on sepsis as a prevalent condition that accounts for 10% of admissions to intensive care units (ICUs) and is associated with a 10-20% in-hospital mortality rate. Standardised protocols and physician awareness have significantly improved survival, but mortality rates remain between 20% and 36%, with ~270,000 deaths annually in the United States. However, of patients with sepsis, 80% are treated in an emergency department (ED), and the remainder develops sepsis during hospitalisation with other conditions. In 2016, the Society of Critical Care Medicine/European Society of Intensive Care Medicine (SCCM/ESICM) task force redefined sepsis based on organ dysfunction and mortality prediction. Sepsis now is defined as life-threatening organ dysfunction caused by dysregulated host response to infection. This definition emphasises the complexity of the disease that cannot be explained by infection or body response to it. Acute change in Sequential Organ Failure Assessment (SOFA) score ≥2 indicates sepsis-related organ dysfunction, a predictor of excess in-hospital mortality. Systemic Inflammatory Response Syndrome (SIRS) and "severe sepsis" terms were omitted from the most recent definition. SIRS has been criticised for its poor specificity, while "severe sepsis" may underestimate sepsis's seriousness. A subset of patients may develop septic shock with underlying profound organ dysfunction and excess mortality. Clinically, septic shock is defined as persistent hypotension requiring vasopressors to maintain mean arterial pressure (MAP) ≥ 65 mm Hg and serum lactate level ≥ 2 mmol/L (18 mg/dL) despite adequate volume resuscitation. Early identification of a patient with infection who may develop sepsis is of utmost importance. Unfortunately, this remains elusive because no single clinical measure or test can reflect complex pathophysiological changes in patients with sepsis. However, multiple clinical and laboratory parameters indicate impending sepsis and organ dysfunction. Screening tools using these parameters can help identify the condition, such as SIRS, quick SOFA (qSOFA), National Early Warning Score (NEWS), or Modified Early Warning Score (MEWS). The 2016 SCCM/ESICM task force recommended using qSOFA, while the 2021 Surviving Sepsis Campaign strongly recommended against its use compared with SIRS, NEWS, or MEWS as a single screening tool for sepsis or septic shock. We hypothesised that qSOFA has greater prognostic accuracy than SIRS and EWS (NEWS/NEWS2/MEWS).

Inclusion Criteria:

1. Adult patients (age ≥18 years),
2. Suspected infection (based on the opinion of the emergency physician),
3. Planned for hospitalization,
4. Willing to give oral informed consent (if required by recruiting center's IRB).

Exclusion Criteria:

1. Presentation to ED is not due to infection (e.g., autoimmune diseases, myocardial infarction, stroke, venous thromboembolism, trauma, intoxication … etc.),
2. Pregnancy,
3. Transferred from another hospitals,
4. Code status is "Do-Not-Resuscitate" (DNR)
5. Elective admission through ED
6. Initial diagnosis of infection in the ED was not confirmed after finishing of the recruitment and follow-up phase.

All consecutive adult patients (age ≥18 years) presenting to the ED with suspected infection who planned to be hospitalized and willing to give informed consent (if required by recruiting center IRB) are eligible. A presumptive diagnosis of infection will be judged based on the opinion of the emergency physician upon the initial patient presentation to the ED. We will exclude patients with evidence of other causes of presentation to the ED other than infection (e.g., autoimmune diseases, myocardial infarction, trauma, …etc.), pregnant ladies, those who transferred from other hospitals, those not planned for hospitalization, or those who admitted electively to the hospital through ED. We will also exclude patients whose initial diagnosis of infection in the ED was not confirmed after the recruitment and follow-up.