Biomarkers for the differentiation of sepsis and SIRS: the need for the standardisation of diagnostic studies

Introduction Sepsis is a leading cause of death in the critically ill patient. It is a heterogeneous disease and it is frequently difficult to make an unequivocal and expeditious diagnosis. The current 'gold standard' in diagnosing sepsis is the blood culture but this is only available after a significant time delay. Mortality rates from sepsis remain high, however, the introduction of sepsis care bundles in its management has produced significant improvements in patient outcomes. Central to goal-directed resuscitation is the timely and accurate diagnosis of sepsis. The rapid diagnosis and commencement of the appropriate therapies has been shown to reduce the mortality. Materials and methods Biomarkers are already used in clinical practice to aid other more traditional diagnostic tests. In the absence of an adequate gold standard to diagnose sepsis, there has been considerable and growing interest in trying to identify suitable biomarkers. There is currently an unmet need in the medical literature to communicate the importance of the challenges relating to the rapid diagnosis and implementation of goal-directed therapy in sepsis and the underlying concepts that are directing these investigations. This article reviews the more novel biomarkers investigated to differentiate systemic inflammatory response syndrome from sepsis. Conclusion The biomarkers described reflect the difficulties in making evidence-based recommendations particularly when interpreting studies where the methodology is of poor quality and the results are conflicting. We are reminded of our responsibilities to ensure high quality and standardised study design as articulated by the STAndards for the Reporting of Diagnostic accuracy studies (STARD) initiative.