The role of immune and metabolic biomarkers for improved management of sepsis patients.

Sepsis, the body`s overwhelming response to systemic infections, is responsible for significant morbidity, mortality, and financial burden. Pathogens and their antigens stimulate pro- and anti-inflammatory mediators and immune markers which characterize the host defense and orchestrate leukocyte recruitment to the acute site of infection. Different immune and metabolic biomarkers have been studied in relation to sepsis for their diagnostic and/or prognostic aid. Recent studies have provided abundant evidence that specific immune and metabolic biomarkers improve a physician`s ability to guide early sepsis recognition, severity assessment and therapeutic decisions in individual patients. This may allow for a transition from bundled sepsis care (protocols combining several medical practices) to more individualized management. First, lactate has now been widely used for risk stratification and guidance of fluid resuscitation. Second, procalcitonin correlates with risks of bacterial infections and helps guide therapeutic decisions about initiation and withdrawal of anti-microbial therapy. Third, prognostic markers such as pro-adrenomedullin improve early mortality prediction and thereby site-of-care decisions in respiratory infections. For these markers interventional trials have documented their value when integrated in clinical protocols.