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C-reactive protein (CRP) by nephelometry (high-sensitivity)

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

This blood test measures a protein produced by your liver in response to inflammation, helping detect low-level inflammation that may not be obvious otherwise.

Quick summary

["High sensitivity CRP helps track subtle inflammation, often used alongside other tests for early detection of conditions like heart disease or infection."]

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

Key facts at a glance

LOINC
111345-5
Short code
GD1b Gangl IgG Msmt Ser
Synonyms
GD1b Gangl IgG Msmt Ser
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82784
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your doctor may order a high-sensitivity CRP test to monitor chronic conditions like arthritis, cardiovascular risk, or to check for signs of inflammation after surgery, injury, or certain infections. It can also help evaluate responses to treatments for inflammatory diseases.

What to Expect Before the Test

No special preparation is needed. You may have a small needle inserted into your arm to draw blood, similar to other blood tests. If you’re on blood thinners, let your provider know before the test.

What the Results Mean

Results are typically reported in milligrams per liter (mg/L). Elevated levels may indicate inflammation, infection, or autoimmune activity, while very low levels suggest no significant inflammation. Your doctor will interpret results in the context of your overall health.

Common Conditions Monitored

High-sensitivity CRP is often used to assess cardiovascular risk, track inflammatory diseases (like rheumatoid arthritis), or evaluate responses to treatments for conditions like lupus or vasculitis.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

High-sensitivity CRP is a key marker for identifying subtle inflammatory processes that may not be detected by standard CRP tests. It helps clinicians identify patients at higher risk for cardiovascular events, guide treatment decisions for chronic inflammatory diseases, and monitor disease activity in conditions like sepsis or post-surgical inflammation.

Short name

hs-CRP (high-sensitivity C-reactive protein)

Frequently asked questions

What does a high or low CRP level indicate?
A high CRP level suggests inflammation is present, which could be due to infection, injury, autoimmune disease, or other conditions. A low CRP level generally means there is little to no inflammation detected in this test. Your doctor will use these results along with other factors to make a diagnosis or treatment plan.
Can diet or exercise affect CRP levels?
Yes, lifestyle factors like diet, exercise, and weight can influence CRP levels. Eating a heart-healthy diet, staying physically active, and maintaining a healthy weight may help lower CRP levels. Smoking and excessive alcohol consumption can also raise CRP, so quitting or reducing these habits may improve results.
Is there any risk or discomfort with this test?
The test involves a small needle inserted into your arm, which may cause mild discomfort or bruising. Most people feel fine afterward. If you have a bleeding disorder or are on blood thinners, your doctor may take extra precautions to minimize risks.
  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