Matrix metalloproteinase-8 : a useful biomarker to refine the diagnosis of community-acquired pneumonia upon intensive care unit admission?

Abstract

The optimal management of severe community-acquired pneumonia (CAP) requires a prompt and accurate diagnosis. Since clinical, radiological, and biological findings are poorly sensitive or specific, microbiological documentation often slow and unavailing, biomarkers could help to safely withhold antibiotics when the risk of bacterial infection is minimal and steer the diagnostic process towards non-infectious causes of respiratory failure. In our previous study deriving the FAIM3:PLAC8 molecular biomarker, we noticed that MMP8, encoding matrix metalloproteinase-8 (MMP-8), was the most overexpressed gene in confirmed CAP relative to non-infectious differential diagnoses (no-CAP). We investigated in the same cohort if plasma levels of MMP-8 could be a valuable candidate biomarker for the diagnosis of CAP.