C-reactive protein (CRP) by nephelometry
This test measures a protein in your blood that rises when your body is fighting inflammation, often used to check for signs of infection or inflammation.
["High CRP levels may signal inflammation that could affect your health."]
Key facts at a glance
- LOINC
- 69019-8
- Short code
- LPT PW/CD45 NFr Bld FC
- Synonyms
- LPT PW/CD45 NFr Bld FC
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- flow-cytometry
- CPT
- 85610
- SNOMED
- 396252006
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may order this test to monitor conditions like arthritis, heart disease, or infections. It can also help track how well treatments are working or check for hidden inflammation in your body.
What to Expect Before the Test
No special preparation is needed. You may have a small needle inserted into your arm or vein to draw blood. If you’re on blood thinners, let your provider know before the test.
What the Results Mean
Results are typically reported in milligrams per liter (mg/L). Higher than normal levels may indicate inflammation, infection, or other health issues. Your provider will discuss what your results mean in the context of your health.
Common Conditions Monitored
This test helps diagnose or track conditions such as rheumatoid arthritis, heart disease, lupus, or other inflammatory diseases. It can also be used to check for signs of infection or to evaluate how well you’re responding to treatment.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
CRP is a marker for inflammation, which can be triggered by infections, injuries, or autoimmune diseases. High levels may signal an ongoing health concern, even if you don’t have obvious symptoms. Your provider may use these results to guide treatment decisions or adjust medications.
Short name
CRP (High-Sensitivity)
Frequently asked questions
What causes CRP levels to change?
How soon will I get my results?
Can I eat or drink before 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