The C-Reactive Protein (CRP) test is your body's "fire alarm" for inflammation. CRP is a protein made by the liver, and its level rises significantly when there's inflammation or infection anywhere in the body. This test is vital for detecting hidden infections, assessing the severity of a known condition, and monitoring the activity of inflammatory diseases like rheumatoid arthritis or IBD. A simple blood draw provides a clear measure of inflammation. This test helps your doctor see if there is an inflammatory fire, so they can effectively find the why.