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C-reactive protein, serum/plasma concentration (high-sensitivity)

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

This test measures the level of a protein called C-reactive protein in your blood. It helps assess inflammation, which can be linked to conditions like infections, injuries, or certain diseases.

Quick summary

["hs-CRP helps track inflammation, guiding treatment decisions for chronic conditions."]

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

Key facts at a glance

LOINC
48392-5
Short code
C immitis Ab Titr Fld CF
Synonyms
C immitis Ab Titr Fld 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
CPT
86430
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 check for signs of inflammation in your body. High levels might suggest conditions like heart disease, autoimmune disorders, or infections. It can also help monitor treatment progress for conditions like arthritis or other inflammatory diseases.

What Does a High or Low Level Mean?

Elevated levels often indicate inflammation or infection. Very low levels may suggest a lack of inflammation, but this isn’t always the case. Your doctor will interpret results in the context of your overall health and symptoms.

How Is the Sample Collected?

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

What Should You Do Before the Test?

Avoid strenuous exercise or activities that cause stress or inflammation 24 hours before the test. Also, inform your doctor about any medications you’re taking, as some may affect results.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

hs-CRP

Frequently asked questions

C-reactive protein is a marker for inflammation. Chronic, low-level inflammation can be linked to long-term health risks like heart disease or diabetes. It’s often used alongside other tests to assess overall health and guide treatment plans.
hs-CRP is typically measured in milligrams per liter (mg/L) or micrograms per milliliter (µg/mL). While reference ranges vary by lab, normal levels are usually below 1 mg/L. Your doctor will provide specific guidelines based on your test results and health status.
What are the common causes of elevated hs-CRP levels?
Elevated hs-CRP can be caused by infections (like colds or flu), injuries, surgeries, or conditions like arthritis, heart disease, or autoimmune disorders. Lifestyle factors such as smoking, obesity, or poor diet may also contribute.
How often should I get this test?
Your doctor will determine how often you need this test based on your health condition and symptoms. Some people may need it yearly, while others may require it more frequently depending on their treatment plan.
  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