C-reactive protein (CRP) by nephelometry (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 doctors assess inflammation, often used to monitor conditions like infections, autoimmune diseases, or after surgery."]
Key facts at a glance
- LOINC
- 105030-1
- Short code
- OXA244
- Synonyms
- blaOXA-244 Islt/Spm Ql
- Category
- chemistry
- Sample
- serum
- Container
- Sterile transport container or nucleic acid preservation tube; avoid containers with preservatives that may inhibit PCR
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- molgen
- CPT
- 87798
- SNOMED
- 415684004
- Specimen volume
- 1-2 mL of serum or appropriate clinical specimen (e.g., rectal swab, urine, blood culture isolate)
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or lower): 30 days for nucleic acid preservation
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order CRP testing to check for signs of inflammation. This can help diagnose conditions like infections (e.g., pneumonia, urinary tract infections), autoimmune diseases (e.g., rheumatoid arthritis), or to monitor healing after procedures or injuries. It may also be used to evaluate risk for heart disease or to guide treatment decisions.
What Does a High or Low CRP Level Mean?
A high CRP level often indicates inflammation or infection. While a low level usually suggests no active inflammation, it doesn’t rule out all causes. Your provider will interpret results in the context of your overall health and symptoms.
How Is the Test Performed?
A blood sample is drawn from a vein in your arm. The plasma is then analyzed using nephelometry, a method that measures how particles scatter light to detect CRP levels.
What Should You Do Before the Test?
Avoid strenuous exercise or extreme stress 24 hours before the test, as these can temporarily raise CRP levels. If you’re on medication, let your provider know, as some may affect results.
Reference range
Negative for blaOXA-244 gene (Target Not Detected). Result reported as Detected or Not Detected.N/A
No special patient preparation required. Collect specimen prior to administration of antimicrobial agents when possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
CRP (Plasma)
Frequently asked questions
Can CRP levels change with diet or exercise?
Is CRP testing painful?
How often should CRP be checked?
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