C-reactive protein (CRP) by turbidimetry (serum/plasma)

Why Is This Test Done?

Your healthcare provider may order this test to check for signs of inflammation. It can help diagnose conditions like infections (e.g., pneumonia, urinary tract infections), autoimmune diseases (e.g., rheumatoid arthritis), or to monitor conditions like heart disease or kidney problems. It may also be used before surgery to assess risk or after surgery to monitor healing.

What Does a High or Low CRP Level Mean?

A higher CRP level often indicates inflammation. For example, very high levels may suggest severe infections or conditions like sepsis. Very low levels might mean there’s little to no inflammation, but this can also happen in some chronic conditions or with certain medications. Your results will be interpreted by your healthcare provider based on your overall health and symptoms.

Sample Collection and Preparation

A blood sample is drawn from a vein, usually in your arm. You may feel a small pinch when the needle is inserted, but the procedure is quick. The blood is then processed to separate the serum or plasma for testing. This test does not require fasting, but let your provider know about any medications or recent illnesses that could affect results.

What to Expect Before or After the Test

There are usually no special preparations needed for this test. After the blood draw, you can resume normal activities immediately. If you experience bruising, swelling, or discomfort at the site, apply a cold compress or take over-the-counter pain relievers as needed. Avoid heavy exercise or strenuous activities for a few hours after the draw.