C-reactive protein (CRP) by nephelometry (serum/plasma)
This test measures the level of C-reactive protein, a protein produced by the liver in response to inflammation or infection in your body.
["CRP helps track inflammation, guiding treatment for conditions like infections or autoimmune diseases."]
Key facts at a glance
- LOINC
- 38278-8
- Short code
- LPT 1.0 ug/mL CA Bld-aCnc
- Synonyms
- LPT 1.0 ug/mL CA Bld-aCnc
- 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
- 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 Is This Test Done?
Your healthcare provider may order a CRP test to check for signs of inflammation, monitor chronic conditions like arthritis or heart disease, or evaluate infections. It can also help assess how well you’re responding to treatment for these conditions.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast before the test, but this depends on your doctor’s instructions. Bring any medications you’re taking, as some may affect results.
What Happens During the Test?
A healthcare professional will draw blood from a vein in your arm. You may feel a small pinch, but it usually doesn’t cause discomfort. The blood sample is then sent to a lab for analysis.
What Are the Possible Results?
Results are reported in milligrams per liter (mg/L) or micrograms per milliliter (µg/mL). Higher than normal levels may indicate inflammation, infection, or other health issues. Your doctor will interpret the results in the context of your medical history and symptoms.
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.
Elevated CRP levels often signal inflammation, which can be linked to infections (like pneumonia or urinary tract infections), autoimmune diseases (such as rheumatoid arthritis or lupus), or other conditions like heart disease or cancer. Lower levels may suggest reduced inflammation. CRP is a useful marker for monitoring disease activity and treatment progress.
Short name
CRP (Nephelometry)
Frequently asked questions
Will this test affect my medications?
Can I eat or drink before this test?
How long will I wait for my results?
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