C-reactive protein (CRP) mass concentration in serum/plasma

What Is C-Reactive Protein (CRP) Used For?

CRP is primarily used to detect inflammation in your body. High levels may signal infections (such as pneumonia or urinary tract infections), autoimmune diseases (like rheumatoid arthritis), or other inflammatory conditions. It can also help assess how well your body is responding to treatment for these conditions or after procedures like surgery or a heart attack.

When Might You Need This Test?

Your healthcare provider may order a CRP test if you have symptoms of inflammation, such as fever, pain, or swelling, or if you’re being evaluated for conditions like heart disease, infections, or autoimmune disorders. It’s also sometimes used as a screening tool before certain procedures.

How Is the Test Performed?

A blood sample is taken from a vein in your arm. The blood is then sent to a lab, where it’s analyzed to measure the CRP levels. The test typically takes a few hours to complete, and results are usually available within a day or two.

What Do CRP Results Mean?

CRP results are reported in milligrams per liter (mg/L). While reference ranges can vary slightly by lab, higher than normal levels may indicate inflammation, while lower levels suggest reduced inflammation. Your healthcare provider will interpret the results in the context of your overall health and symptoms.