C-reactive protein, serum/plasma concentration (high-sensitivity)
This test measures a protein called C-reactive protein (CRP) in your blood. CRP is produced by your liver in response to inflammation.
["hsCRP helps assess low-level inflammation in your body."]
Key facts at a glance
- LOINC
- 70666-3
- Short code
- COLDAG
- Synonyms
- CA Ser Ql 22 deg C inc
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top tube without anticoagulant. EDTA plasma is NOT acceptable as it may interfere with agglutination reactions.
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- deg-c-incubation
- CPT
- 86156
- SNOMED
- 10128-6
- Specimen volume
- 1-2 mL serum (minimum 0.5 mL)
- Stability
- Serum must be separated from red blood cells immediately and kept at 37°C prior to testing to prevent cold autoabsorption. Once separated, serum is stable for 24 hours at room temperature (22°C) or 7 days at 2-8°C. For prolonged storage, freeze at -20°C or below. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 100
- Icterus max
- 50
- TAT
- 24–72 hours
- Order
- routine
Why Is This Test Done?
Your doctor may order this test to monitor chronic conditions like heart disease, arthritis, or other inflammatory disorders. High-sensitivity CRP is also used to evaluate risk for future heart problems or to check for signs of infection or inflammation after surgery or injury.
What to Expect Before the Test
No special preparation is needed. You may have a small needle inserted into a vein in your arm, and a blood sample will be drawn. If you’re on blood thinners, let your doctor know before the test.
What the Results Mean
Results are typically reported in milligrams per liter (mg/L). While reference ranges vary by lab, higher levels may indicate inflammation, infection, or autoimmune activity. Very low levels might suggest no significant inflammation.
Common Conditions Monitored
This test is often used alongside other markers to track conditions like cardiovascular risk, rheumatoid arthritis, or post-surgical healing. It’s not a standalone diagnosis but a tool for ongoing assessment.
Reference range
Negative (no cold agglutinins detected at 22°C). A titer ≥1:64 is generally considered clinically significant. Normal individuals may have low-titer cold agglutinins (≤1:16) without clinical disease.N/A
No special patient preparation required. Fasting is not necessary. Patients should be informed that sample collection involves standard venipuncture.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: hsCRP’s Role in Healthcare
Short name
hsCRP
Frequently asked questions
What does a high hsCRP level mean?
Can diet or exercise affect hsCRP 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 15, 2026. · Read our editorial policy