Serum amyloid A protein is a type of polymorphic protein family and is encoded by a series of genes. It’s the precursor of tissue amyloid A protein and a sensitive acute-phase reactant.The normal concentration of SAA in healthy human’s serum is lower than10 mg/L. It will rise rapidly to 1000 times of the initial concentration during the preliminary phase of inflammation or other diseases, and decrease to the normal level quickly during recovery.
SAA level will increase both in viral and bacterial infection, while CRP rise barely or slightly in viral infection . The combination of SAA detection and CRP will discern viral infection, non-invasive or prodromal invasive bacterial infection while CRP detection shows normal, so the combination will offer reference for the distinction of infectious diseases andselection of the therapeutic plan.