A diagnostic devise, namely HemoSpec, had been developed that integrates clinical information, along with information on circulating protein biomarkers and the morphology of white blood cells to achieve early diagnosis of sepsis. The current study is aiming to validate and improve performance of HemoSpec for the rapid assessment of the critically ill patient in the Emergency Department.

Sepsis is a life-threating organ dysfunction resulting from the dysregulated response of the host to an infection. It is estimated that 1.5 million people present with sepsis annually in Northern America and another 1.5 million people in Europe; 30 to 50% of them die making sepsis the leading cause of death. The key-point in the management of sepsis is the early resuscitation with broad- spectrum antimicrobials and intravenous fluids, if possible within the first hour. However, it is not easy to achieve this goal, especially among patients assessed in the Emergency Department (ED), as the diagnosis of an infection is often delayed until the patient's laboratory and imaging tests are completed.

In an attempt to improve the failure of physicians for early sepsis recognition in the ED, several markers have been developed. The most widely used biomarkers are the absolute number of neutrophils, C-reactive protein (CRP) and procalcitonin (PCT). HemoSpec is a device capable of incorporating clinical information from the patient with laboratory data. The analysis provides information on white blood cell morphology, CRP, PCT, interleukin (IL) -6 and suPAR. The device software has been created from all of the above information collected from prospective cohorts of patients from Greece and Germany. The diagnostic function of HemoSpec has so far been validated in two Phase II studies. The first study took place in Germany and involved 60 patients (20 controls, 20 with systemic inflammatory response and 20 with sepsis) who were hospitalized at the University Hospital in Jena. The second study is currently being conducted in Greece and aims to use the information from the HemoSpec device for the prospective categorization of patients with confirmed infection in patients with sepsis and in patients without sepsis.

The above two studies share a common Phase II design in order to validate HemoSpec's diagnostic ability among patients who are clinically diagnosed with sepsis. The clinical reliability of HemoSpec can be verified in a multicenter prospective trial involving patients assessed in the ED. The present study aims to assess the diagnostic ability of the device in ED patients with clinical signs of infection who have a significant risk of death that makes them likely to suffer from sepsis.

Inclusion Criteria:

• Admission in the Emergency Department
• Age above or equal to 18 years old
• Both genders
• Written consent provided from patients or their first-degree relatives for patients unable to consent
• Considerable risk of death as indicated by the presence of at least one of the following: i) sudden alteration of mental status; ii) systolic blood pressure less than 100 mmHg; and iii) high respiratory rate defined as more than or equal to 22 breaths per minute.

Exclusion Criteria:

• Known infection by the human immunodeficiency virus-1
• Acute myocardial infarction as evidenced by the electrocardiographic finding of ST- elevation.
• Single trauma or multiple injuries
• Known pregnancy and breastfeeding
• Patients with a life expectancy of less than 28 days and with limited treatment options