Infectious diseases are disorders caused by many different microorganisms that produce clinical conditions with a wide variation in patient-rated symptoms and severity. Therefore, different diagnostic and prognostic tools are needed to help make the most accurate decisions at each moment of patient´s care with suspected infection. This mini review will analyse how some biomarkers reduce the level of uncertainty in the making decision process at some phases of sepsis, including prompt identification of septic patients, early initiation of empiric broad-spectrum antimicrobials, regimen and duration.