Serum amyloid A (SAA) is a major acute phase protein in human beings, and dogs. The level of SAA proteins in blood increases within just a few hours following the onset of various inflammatory stimuli. These include infection, trauma and surgery

Clinical Significance

Its concentration depends on clinical findings of the patient, illness activity and the therapy applied. SAA increases moderately to markedly (100-1000 mg/l) in bacterial and fungal infections, invasive malignant diseases, tissue injuries in the acute myocardial infarction and autoimmune diseases such as rheumatoid arthritis and vasculitis. Mild elevation (10-100 mg/l) is often seen in viral infections, systemic lupus erythematosus and localized inflammation or tissue injuries in cystitis and cerebral infarction. SAA as sensitive, non-invasive parameter is used in organ transplantation where early and correct diagnosis is needed as well as where prompt therapy is required. Besides acute kidney allograft rejection, SAA is used in the diagnosis of rejection after liver transplantation, simultaneous pancreas and kidney transplantation and also in bone marrow transplantation (acute "graft vs. host disease").