Skip to content

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

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 or infection.

Quick summary

["CRP helps identify inflammation in your body, often used to check for infections or other health conditions."]

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

Key facts at a glance

LOINC
109910-0
Short code
C immitis IgG Msmt CSF
Synonyms
C immitis IgG Msmt CSF
Category
chemistry
Sample
csf
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82784
Specimen volume
1-2 mL
Stability
Immediate analysis required, Refrigerated: 1h
Hemolysis max
200
TAT
4–24 hours
Order
routine

Why This Test Might Be Ordered

Your healthcare provider may order this test to monitor inflammation, check for infections like pneumonia or sepsis, evaluate conditions such as rheumatoid arthritis or heart disease, or assess response to treatment for inflammatory diseases.

What to Expect Before the Test

No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it involves drawing blood from a vein. Avoid strenuous activity or aspirin/ibuprofen 24 hours before testing, as they can affect inflammation markers.

What Happens During the Test

A healthcare professional will draw blood from a vein in your arm using a small needle. The blood sample is then sent to a lab for analysis using a nephelometry method to measure CRP levels.

What the Results Mean

Results are typically reported in milligrams per liter (mg/L). Higher than normal levels may indicate inflammation, infection, or other underlying health issues. Your provider will interpret results in the context of your medical history and symptoms.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CRP (Nephelometry)

Frequently asked questions

What does a high CRP level mean?
A high CRP level suggests inflammation in your body, which could be due to infections, autoimmune diseases, or other health problems. Your doctor will discuss the cause and next steps based on your symptoms and test results.
What does a low CRP level mean?
A low CRP level usually means there is little to no inflammation detected in your body. However, it doesn’t rule out all causes of inflammation, so your doctor may order additional tests if needed.
Can CRP levels change with diet or exercise?
Yes, lifestyle factors like diet, exercise, and stress can influence CRP levels. Avoiding processed foods, managing weight, and staying physically active may help reduce inflammation over time.
  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