C-reactive protein, serum/plasma concentration (high-sensitivity)
This test measures a protein produced by your liver in response to inflammation or infection. It helps assess whether inflammation is present in your body.
["hs-CRP helps track inflammation, a key marker for conditions like heart disease or autoimmune disorders."]
Key facts at a glance
- LOINC
- 70667-1
- Short code
- COLDAGG
- Synonyms
- CA Ser Ql 28 deg C inc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube (no anticoagulant) or serum separator tube (SST); tube must be pre-warmed to 37 degrees C prior to collection
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- deg-c-incubation
- CPT
- 86157
- SNOMED
- 55207009
- Specimen volume
- 3-5 mL whole blood (minimum 1 mL serum)
- Stability
- Serum should be separated from cells immediately after collection and maintained at 37 degrees C during processing. For testing, serum may be refrigerated (2-8 degrees C) for up to 24 hours. For prolonged storage, freeze at -20 degrees C or below for up to 2 weeks. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
Why Is This Test Done?
Doctors may order hs-CRP to monitor chronic conditions like heart disease, rheumatoid arthritis, or other inflammatory diseases. It can also help evaluate risk after a heart attack or stroke or guide treatment decisions for conditions like lupus or inflammatory bowel disease.
What Does a High or Low Result Mean?
A higher-than-normal hs-CRP level suggests increased inflammation. A lower level may indicate reduced inflammation, though it doesn’t always mean no inflammation is present. Results are interpreted based on your overall health and medical history.
How Is the Test Performed?
A blood sample is drawn from a vein, usually in your arm. The sample is sent to a lab where it is analyzed using a sensitive immunoassay method to measure hs-CRP concentration.
What Are Common Causes of Abnormal Results?
Increased hs-CRP levels can occur with infections, injuries, autoimmune diseases, or conditions like obesity or diabetes. Low levels may be normal, but they can also occur with certain medications or in people with very low inflammation.
Reference range
Negative (no agglutination observed at 28 degrees C). A positive result is reported qualitatively as detected or not detected. Titer, if performed, is typically reported with the highest dilution showing agglutination (e.g., <1:64 considered normal by most laboratories; clinical significance usually at titers >1:64 or >1:256).N/A
No special patient preparation required. Fasting is not necessary. However, it is recommended that the specimen be drawn and kept at 37 degrees C until serum is separated to prevent in vitro cold agglutinin adsorption to red blood cells, which may cause false-negative results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: hs-CRP plays a critical role in assessing cardiovascular risk and guiding preventive care. It helps doctors tailor treatments to reduce inflammation-related complications, such as plaque buildup in arteries.
Short name
hs-CRP
Frequently asked questions
What does a high hs-CRP level mean for my long-term health?
Can diet or exercise affect hs-CRP levels?
How often should I get this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy