What is C-Reactive Protein?
C-reactive protein is an acute-phase pentraxin synthesised by hepatocytes in response to interleukin-6 and other inflammatory cytokines. It rises within hours of an inflammatory or infective stimulus and falls rapidly once the stimulus resolves, with a plasma half-life of around 19 hours, so its concentration tracks current inflammatory activity closely. The standard CRP assay quantifies the higher concentrations seen in overt inflammation and infection.