C-reactive protein (mass concentration) in serum/plasma
This test measures the level of C-reactive protein, a protein produced by the liver in response to inflammation in your body.
["CRP helps identify and monitor inflammation, often used to check for infections or other inflammatory conditions."]
Key facts at a glance
- LOINC
- 99369-1
- Short code
- Cocksfoot IgG-mCnc
- Synonyms
- Cocksfoot IgG-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 22
- Ref high
- 198
- Critical range
- — – 10000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82553
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order a CRP test to evaluate signs of inflammation, detect infections (such as pneumonia or urinary tract infections), or monitor conditions like rheumatoid arthritis, heart disease, or autoimmune disorders. It can also help assess how well your body is responding to treatment for these conditions.
What to Expect Before the Test
No special preparation is usually needed. You may have a small needle inserted into your arm to draw blood. If you’re on blood thinners, let your provider know before the test.
What the Results Mean
CRP levels can vary based on health status, age, and other factors. Higher levels often indicate inflammation or infection, while lower levels suggest minimal or no inflammation. Your results will be discussed with you by your healthcare provider.
Common Conditions Monitored
CRP is commonly used to monitor conditions like infections, inflammatory diseases (such as lupus or arthritis), and to check for early signs of heart disease or other chronic inflammatory conditions.
Reference range
Adult males: 22-198 U/L; Females: 22-198 U/LN/A
No special preparation required. Inform provider of any chest pain or symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: CRP plays a critical role in diagnosing and managing inflammatory and infectious diseases. Elevated CRP levels can signal an active inflammatory process, guiding treatment decisions and follow-up care. It’s often used as a screening tool or to assess disease activity in conditions where inflammation is a key factor.
Short name
CRP (Serum/Plasma)
Frequently asked questions
What causes CRP levels to be high?
How long does it take to get CRP test results?
Can CRP levels be affected by diet or lifestyle?
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 17, 2026. · Read our editorial policy