The level of c-reactive protein (CRP) in your blood is examined by a c-reactive protein test. CRP is a protein that your liver produces. Inflammation causes it to be released into your circulation. When you've been harmed or have an infection, your body uses inflammation to defend your tissues. In the damaged or afflicted region, it might produce discomfort, redness, and edema. Inflammation can also be caused by autoimmune illnesses and chronic diseases. C-reactive protein levels in your blood are normally low. High levels may be a sign of a serious infection or other disorder.