Serum Amyloid A Blood Test (SAA)

Serum Amyloid A (SAA) is an acute-phase protein produced by the liver in response to inflammation, infection, or tissue injury. This blood test measures the level of SAA in your bloodstream to help identify and monitor inflammatory conditions. It is particularly useful when standard inflammatory markers such as CRP are normal but clinical suspicion of inflammation remains, as SAA can rise earlier and more dramatically in response to acute events.

This test is suitable for adults and children who are being investigated for unexplained fever, suspected infection, chronic inflammatory diseases (such as rheumatoid arthritis, inflammatory bowel disease, or vasculitis), or for monitoring the response to treatment in known inflammatory conditions. It may also be requested as part of a broader assessment of joint pain, persistent fatigue, or recurrent infections.

Inflammation
- Serum Amyloid A (SAA): an acute-phase protein that increases rapidly within hours of an inflammatory stimulus. Elevated levels can indicate acute infection, active inflammation, or tissue damage. Persistently high SAA may be associated with chronic inflammatory disorders or, rarely, with conditions such as amyloidosis.

Why it matters
SAA provides an early and sensitive signal of inflammation, often before other markers become abnormal. This can help your doctor identify the cause of symptoms more quickly, monitor disease activity, and assess how well a treatment is working. Early detection and monitoring of inflammation can lead to more timely and targeted care, potentially preventing complications associated with untreated inflammatory conditions.