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C-reactive protein (CRP) by immunoturbidimetric assay (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

["CRP helps doctors assess inflammation and identify possible infections or autoimmune conditions."]

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

Key facts at a glance

LOINC
92798-8
Short code
C lusitaniae DNA Bld Pos Ql NAA+probe
Synonyms
C lusitaniae DNA Bld Pos Ql NAA+probe
Category
chemistry
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
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 CRP Matters in Your Health

CRP is often checked when you have symptoms like fever, fatigue, or joint pain, or if your doctor suspects an infection, inflammation, or other health issues. It can also be used to monitor conditions like heart disease or rheumatoid arthritis.

What to Expect During the Test

A small blood sample is taken from a vein in your arm. You may feel a slight pinch, but it usually doesn’t cause much discomfort. The sample is then sent to a lab for testing.

Common Reasons for Testing

Your doctor might order this test if you have symptoms of inflammation, such as swelling, redness, or pain, or if you have a known condition that affects inflammation levels. It can also be used as part of routine check-ups or to monitor chronic health conditions.

What the Results Mean

Results are not typically interpreted alone but are compared to your overall health and symptoms. Higher CRP levels may indicate inflammation, while lower levels suggest reduced inflammation. Your doctor will discuss these results with you.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: CRP’s Role in Diagnosing and Managing Health Conditions

Short name

CRP (Serum/Plasma)

Frequently asked questions

What does a high CRP level mean?
A high CRP level often signals inflammation in your body, which can be caused by infections (like pneumonia or urinary tract infections), autoimmune diseases (like lupus or rheumatoid arthritis), or other inflammatory conditions. It can also be elevated after surgery or trauma. Your doctor will consider your symptoms and other test results to determine the cause.
What does a low CRP level mean?
A low CRP level usually means there is less inflammation in your body. However, it doesn’t necessarily mean you’re healthy. CRP can be low if you have a mild or controlled inflammatory condition, or if you’re not experiencing symptoms. Always discuss your results with your healthcare provider.
Can CRP levels change over time?
Yes, CRP levels can change based on your health status, recent illnesses, medications, or lifestyle factors like diet and exercise. Regular monitoring can help track how well treatments for inflammation or chronic conditions are working.
  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