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C-Reactive Protein (CRP) with High-Sensitivity Measurement

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

This test measures a protein in your blood that rises when your body has inflammation, often used to check for low-grade inflammation or risk of heart disease.

Quick summary

["High CRP levels may signal inflammation or increased cardiovascular risk—your doctor will interpret results with your symptoms and other tests."]

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

Key facts at a glance

LOINC
20768-8
Short code
C immitis Ab Ser Ql CF
Synonyms
C immitis Ab Ser Ql CF
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
comp-fix
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 Is This Test Done?

Your doctor may order this test to monitor chronic conditions like arthritis, heart disease, or infections. It can also help assess inflammation after surgery, injury, or during routine check-ups for heart health.

What Does It Measure?

The test detects the presence of C-reactive protein, a marker produced by your liver in response to inflammation. It’s often measured in very small amounts, so high-sensitivity methods are used to detect even slight increases.

How Is It Done?

A blood sample is drawn from a vein in your arm. The sample is sent to a lab where it’s analyzed to measure CRP levels. Results are typically ready within 24 hours.

What Do Results Mean?

Results are compared to a general reference range, but your doctor will consider your overall health and other factors. Elevated levels may indicate inflammation, infection, or conditions like autoimmune diseases or heart disease.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: CRP is a key marker for inflammation and cardiovascular risk. While not a direct measure of disease, it helps guide treatment decisions, especially in conditions like rheumatoid arthritis or after a heart attack. Persistently high levels may prompt further evaluation for underlying causes.

Short name

hs-CRP (Serum)

Frequently asked questions

What causes CRP levels to be higher than normal?
Infections (like colds or urinary tract infections), injuries, surgeries, or certain medical conditions (such as autoimmune diseases) can raise CRP levels. Stress or recent illness may also temporarily increase it.
How soon after an injury or illness will CRP levels rise?
CRP levels typically rise within days after an injury or infection and may peak in a few weeks before returning to normal. Timing depends on the cause, but results are usually interpreted with your doctor’s guidance.
Can lifestyle changes lower CRP levels?
Yes! Reducing inflammation through diet (e.g., Mediterranean diet), exercise, quitting smoking, and managing stress may help lower CRP levels over time. Always discuss lifestyle changes with your doctor before making major adjustments.
  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