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C-reactive protein (CRP) by nephelometry (plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the level of C-reactive protein, a protein produced by the liver in response to inflammation in your body.

Quick summary

["CRP helps track inflammation, often used to monitor conditions like infections, autoimmune diseases, or after surgery."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
96488-2
Short code
NIF-H IgG CSF Ql CBA IFA
Synonyms
NIF-H IgG CSF Ql CBA IFA
Category
chemistry
Sample
csf
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
cba-ifa
CPT
82784
Specimen volume
1-2 mL
Stability
Immediate analysis required, Refrigerated: 1h
Hemolysis max
200
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your doctor may order a CRP test to check for signs of inflammation, monitor chronic conditions like rheumatoid arthritis or lupus, or evaluate your response to treatment. It can also help identify infections, such as pneumonia or sepsis, especially when other tests are inconclusive.

What to Expect Before the Test

No special preparation is needed. You may have a small needle inserted into your arm to draw a blood sample. If you’re on blood thinners, inform your doctor beforehand.

What the Results Mean

Higher CRP levels often indicate inflammation, but results alone don’t diagnose a specific condition. Your doctor will interpret the results in the context of your symptoms and medical history.

Common Conditions Monitored

CRP is commonly used to monitor conditions like inflammatory diseases, infections, or post-surgical recovery. It’s also part of screening for cardiovascular risks in some cases.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CRP Plasma

Frequently asked questions

What causes CRP levels to rise?
CRP levels can increase due to infections (like colds or flu), injuries, surgeries, or certain medical conditions such as autoimmune diseases (e.g., rheumatoid arthritis). Stress or certain medications may also affect CRP levels.
How long does it take to get results?
Results are typically available within 24 to 48 hours, depending on your lab’s processing time. Your doctor will discuss the findings with you during your follow-up visit.
Can I eat or drink before this test?
You can eat and drink normally before the test, as no fasting is required. However, always follow your doctor’s specific instructions if they’ve provided any.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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