Novel biomarkers of infection in the critically ill
Over 25% of all annual deaths in the world are due to infection. Early diagnosis and risk stratification facilitate timely and specific treatment, but are complicated by the highly variable and non-specific nature of the signs and symptoms of sepsis. There is a lack of a ‘gold standard’ for the diagnosis of infection or sepsis, prognosis of severe infections, and sepsis. There are several biomarkers that have been investigated in literature like white blood count, C-reactive protein, procalcitonin, sTREM1, etc., with equivocal results. White blood count and C-reactive protein are elevated in states of inflammation without infection and sepsis. Therefore, they have low specificities for diagnosis of infection. The future is promising with development of high sensitivity assays, molecular strategies, and a ‘panel approach’, all of which need to be investigated in well-designed future studies. At present, there is insufficient evidence for the routine use of novel biomarkers in infection and sepsis.