CRP vs hsCRP: Key Differences Explained
Learn how standard CRP and high-sensitivity CRP measure the same protein at different concentration ranges and answer different clinical questions.
Standard C-reactive protein (CRP) and high-sensitivity C-reactive protein (hs-CRP) tests measure the same protein in blood. The main difference is the concentration range each assay is designed to measure and the clinical question it is used to answer.
Neither test identifies where inflammation is occurring or what caused it. Results need to be interpreted with symptoms, medical history, other tests, and the reporting laboratory’s reference information.
What is a standard CRP test?
A standard CRP test measures changes in C-reactive protein associated with inflammation. It is commonly used to evaluate or monitor infections, inflammatory conditions, tissue injury, or response to treatment.
CRP is nonspecific. An elevated result indicates that inflammation may be present, but it cannot diagnose a particular condition or identify the location of inflammation on its own.
What is an hs-CRP test?
An hs-CRP test measures lower concentrations of the same C-reactive protein. It may provide additional information during cardiovascular-risk assessment.
hs-CRP is not a stand-alone cardiovascular-risk score. Its meaning depends on established risk factors and the reason for testing.
CRP versus hs-CRP
Question | Standard CRP | High-sensitivity CRP |
|---|---|---|
What does it measure? | C-reactive protein in blood | The same C-reactive protein in blood |
What is different? | Designed for the concentration range used when evaluating larger inflammatory responses | Designed to measure lower CRP concentrations with greater precision |
Common clinical question | Is inflammation present or changing in the context of an illness or inflammatory condition? | Could inflammation add information to an overall cardiovascular-risk assessment? |
What can it diagnose by itself? | Neither the cause nor location of inflammation | Neither the cause of inflammation nor cardiovascular disease |
Which test should you choose?
The appropriate test depends on the question you are trying to answer, not on which assay sounds more precise.
- If you are testing in a preventive cardiovascular context with no active illness, hs-CRP is the assay designed for that question.
- Standard CRP earns its place when you and your doctor are tracking an infection, an injury, or a diagnosed inflammatory condition.
If it is unclear which question you are trying to answer, ask your doctor which test fits.
Do you need both tests?
Not routinely. Ordering one or both depends on the question being evaluated. Using both does not automatically provide a more complete picture, and the results should not be treated as interchangeable risk categories.
Limitations both tests share
- Neither test identifies the cause or location of inflammation.
- A result may change with illness, injury, surgery, or another temporary inflammatory event. Retesting after recovery can give a more representative baseline.
- Reference information and units can vary by laboratory.
- Greater analytical sensitivity does not make hs-CRP the better assay for every clinical question.
- A lower result does not rule out every inflammatory condition or determine cardiovascular risk by itself.
Frequently asked questions
- Is hs-CRP a different biomarker from CRP? No. It is a more sensitive assay for lower concentrations of the same C-reactive protein.
- Do you need to fast? No. You don’t need to fast for hs-CRP on its own. If other tests are collected at the same visit, follow the instructions on your order.
- Can medicines or supplements affect the result? Some medicines and supplements can affect CRP measurement or interpretation. Do not stop a prescription medicine because of a result without speaking with your doctor or prescribing clinician.
- Does a high hs-CRP result mean heart disease is present? No. hs-CRP may add information to an overall cardiovascular-risk assessment but does not diagnose cardiovascular disease.
Order the individual hs-CRP test
If you want the high-sensitivity measurement on its own, view the individual hs-CRP test for current member and non-member pricing, availability in your state, and checkout.
For detailed definitions and interpretation limitations, see the hs-CRP biomarker reference. For the testing process and product choices, see the hs-CRP blood test guide.
Sources
- MedlinePlus: C-Reactive Protein test
- American Heart Association: hsCRP and cardiovascular-risk assessment
- Mayo Clinic Laboratories: hs-CRP ordering guidance and limitations
Medical disclaimer
This comparison is for informational purposes only and does not provide medical advice, diagnosis, or treatment. It is not a substitute for care tailored to your health history and symptoms.
