C-reactive protein (CRP) concentration, serum/plasma
This test measures the level of C-reactive protein, a protein produced by the liver in response to inflammation in your body. It helps doctors assess whether inflammation is present.
["CRP helps track inflammation, often used to monitor conditions like infections, autoimmune diseases, or after surgery."]
Key facts at a glance
- LOINC
- 98065-6
- Short code
- OXA143
- Synonyms
- blaOXA-143 Islt/Spm Ql
- Category
- chemistry
- Sample
- serum
- Container
- Sterile transport container or bacterial culture swab transport system; molecular-grade collection device preferred
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- CPT
- 87153
- SNOMED
- 122450008
- Specimen volume
- 1-2 mL of clinical specimen or bacterial isolate; minimum 0.5 mL acceptable
- Stability
- Room temperature: 2 hours; Refrigerated (2-8°C): 24-48 hours; Frozen (-70°C or below): extended storage for retrospective testing
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–72 hours
- Order
- routine
Why CRP Matters in Your Health
CRP isn’t specific to any single condition, but it’s a useful marker for detecting and monitoring inflammation. High levels may signal infections, injuries, or inflammatory diseases like rheumatoid arthritis or lupus. Doctors may order this test to check for early signs of problems or to guide treatment decisions.
When This Test Is Done
Your doctor might recommend a CRP test if you have symptoms like fever, joint pain, or unexplained fatigue. It’s also used before surgeries, during chemotherapy, or to evaluate chronic conditions like heart disease or kidney problems. Sometimes, it’s part of a routine checkup to monitor long-term health.
What to Expect Before the Test
No special preparation is needed, but you may be asked to fast for 8–12 hours before the test if it’s part of a fasting panel. On the day of the test, avoid smoking, strenuous activity, or certain medications (like NSAIDs) that could affect results. Bring a list of medications to your doctor’s office.
What the Results Mean
Results are usually reported in milligrams per liter (mg/L). A normal range isn’t always the same for everyone, so your doctor will compare your results to your own baseline or to what’s typical for your condition. Very high levels may prompt further testing, while low levels might raise questions about hidden inflammation.
Reference range
Negative (blaOXA-143 gene not detected); Result reported as Detected or Not DetectedN/A
No special patient preparation required. Specimen should be collected prior to initiation of antimicrobial therapy when possible. Collect from site of suspected infection following standard aseptic technique.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
CRP (Serum/Plasma)
Frequently asked questions
What causes elevated CRP levels?
What if my CRP is high?
Can CRP levels be affected by diet or exercise?
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