C-Reactive Protein (CRP) Blood Test

What Is a CRP Blood Test and Why Is It Done?

A C-reactive protein (CRP) test measures the level of CRP in the blood. CRP is a protein that the liver makes.

Doctors may order a CRP test:

• if someone has signs of inflammation or infection, like a fever, chills, swelling, or pain
• to check how well treatment for inflammation or infection is working
• to follow conditions like inflammatory bowel disease (IBD), arthritis, and lupus

Top Things to Know

• The C-reactive protein (CRP) test checks the level of a protein called CRP in the blood.
• Doctors may order it to look for inflammation or infection, or to see how treatment is working.
• Kids might need to stop taking certain medicines or not eat or drink before the blood test.
• Your doctor can explain what it means if CRP levels are high or low.

How Can I Help My Child Prepare for a Blood Test?

To help kids get ready for a blood test, find out if they need to fast (not eat or drink) or should stop taking medicines before the test. Explain what to expect during the test.

If your child is nervous about it, work together on ways to stay calm. Deep breathing or even imagining being in a place that makes your child feel safe and relaxed can help.

What Do CRP Results Mean?

Your doctor will explain what the results of the CRP test mean for your child. The “normal” range varies based on things like age and gender.

High CRP levels can mean there’s inflammation. Kids will likely need other tests to show where the inflammation is or if they have a condition, like an autoimmune condition (when the immune system damages normal, healthy body tissues). A high CRP level could also be due to an infection.

If kids are receiving treatment and their CRP level is now lower, this might mean that the treatment is working well.

What Else Should I Know?

If you have questions about the CRP test or what the results mean, talk to your doctor.