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

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

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

Quick summary

["Helps assess inflammation or infection and monitor conditions like arthritis, heart disease, or infections."]

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

Key facts at a glance

LOINC
96303-3
Short code
C gattii+neofor DNA Bld Pos Ql NAA+n-prb
Synonyms
C gattii+neofor DNA Bld Pos Ql NAA+n-prb
Category
coagulation
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
non-probe-amp-tar
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 It’s Done

Your healthcare provider may order this test to check for signs of inflammation, monitor chronic conditions, or evaluate symptoms like fever, joint pain, or swelling. It can also be used before surgery or during treatment for certain illnesses.

What to Expect

A small blood sample is taken from a vein in your arm. You may feel a slight pinch, but it usually doesn’t cause discomfort. The test involves sending your blood sample to a lab for analysis.

What the Results Mean

Higher-than-normal CRP levels may indicate inflammation, infections, autoimmune diseases, or other health issues. Lower levels suggest minimal inflammation. Your provider will interpret results based on your medical history and symptoms.

Common Conditions Monitored

CRP is often used to monitor conditions like rheumatoid arthritis, lupus, heart disease, or infections. It can also help track how well treatments are working.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: CRP is a marker for systemic inflammation. Elevated levels can signal acute infections, chronic inflammatory diseases, or conditions like sepsis, where prompt identification may guide treatment decisions. It’s less specific than some other tests but useful for broad screening.

Short name

CRP (Nephelometry)

Frequently asked questions

How often will I need this test?
The frequency depends on your health condition and treatment plan. Some people get CRP tests monthly, quarterly, or annually, while others may need them less often. Your provider will let you know.
What if my CRP level is high?
A high CRP level may mean you have inflammation or infection. Your provider will review your results with you and may recommend further tests or changes to your treatment plan, such as adjusting medications or starting antibiotics.
Can I eat or drink before this test?
You can usually eat and drink normally before this test unless your provider gives specific instructions. Blood tests like CRP don’t require fasting.
  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