High-Sensitivity C-Reactive Protein

This test may be helpful in assessing risk of developing heart disease.

C-reactive protein (CRP) is a substance made by the liver and secreted into the bloodstream, increasing when inflammation is present. CRP has been used for many years as an indicator of bacterial or viral infection and as a monitor of changes in inflammation associated with many inflammatory and autoimmune diseases.

Some studies have shown that CRP also can be an indicator of risk of cardiovascular disease in apparently healthy people. However, the level of CRP in the blood is normally so low that an especially sensitive test is needed to measure it. This test is called high-sensitivity CRP or hs-CRP.

Since the hs-CRP and CRP tests measure the same molecule, people with chronic inflammation, such as those with arthritis, should not have their hs-CRP levels measured. Their CRP levels will be very high due to the arthritis, often too high to be measured using the hs-CRP test.

PREPARATION FOR TEST

A blood sample is obtained by inserting a needle into a vein in the arm.

NORMAL FINDINGS

  • ACUTE PHASE REACTION: >10 mg/L

  • Low cardiovascular risk: 0.0-1.0 mg/L

  • Moderate cardiovascular risk: >1.0-3.0 mg/L

  • High cardiovascular risk: >3.0 mg/L

Ranges for normal findings may vary among different laboratories and hospitals. You should always check with your doctor after having lab work or other tests done to discuss the meaning of your test results and whether your values are considered within normal limits.

MEANING OF TEST

Your caregiver will go over the test results with you and discuss the importance and meaning of your results, as well as treatment options and the need for additional tests if necessary.

OBTAINING THE TEST RESULTS

It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.