Monocytes can contribute to the process of inflammation or infection by secreting cytokines, however, there is increasing evidence that monocytes undergo morphological changes, including volume increase, during inflammatory or infectious processes and sepsis.

   Polilli et al compared patients with no sepsis, sepsis, and septic shock and found that MDW values were significantly higher in patients with sepsis or septic shock than in the no sepsis group.

    As MDW increases in response to bacterial infection in the blood, MDW is related to the blood culture results. Although the blood culture test is the gold standard in diagnosing bacterial infections in the blood, low sensitivity, and false positivity are still valid concerns

Patients to be admitted will be categorized into 3 groups: sepsis, probable sepsis, and control group according to sequential organ failure assessment (SOFA) criteria and Sepsis-3 criteria definitions. Institutions Sepsis Code activation in ER, will also be used as an enrolling tool in this study.

A control group will be taken comprising of patients with no evidence of infection like patients presenting to ICU with Cerebrovascular accident (CVA) without aspiration, class I (clean) post-operative care patients, and head trauma patients.

 All routine blood investigations will be sent including Complete Blood Count (CBC), MDW, and Procalcitonin (PCT), along with all other tests that could define infection, like imaging. 

Blood culture sensitivity (One set of aerobic and anaerobic/ Two sets of aerobic and anaerobic from two different sites if an invasive medical device is present) will be sent in all patients using all standard aseptic precautions. Other cultures will be sent as per the cause of sepsis suspicion.