CRP

Also known as: C-Reactive Protein

Blood Tests Blood
Patient Friendly Summary

If ESR is a smoke detector, CRP is a faster one. Doctors often repeat CRP after starting treatment — a falling CRP suggests the treatment is working.

What this test means

CRP is a protein the liver releases within hours of inflammation or infection starting. It rises and falls faster than ESR, so it is useful for tracking acute illness.

Why it is done

It is done for fevers, suspected bacterial infections, monitoring response to treatment, and evaluating inflammatory conditions.

Understanding your value

If your value is high

High CRP can be seen in bacterial infections, injuries, flare-ups of arthritis, and after surgery. Very high values usually prompt a search for infection.

If your value is low

A low or undetectable CRP is normal and reassuring.

About the normal range

Many labs report normal as below 6 mg/L (or below 0.6 mg/dL). High-sensitivity CRP (hs-CRP) uses different cut-offs for heart risk assessment.

When to consult a doctor

Share raised CRP results with your doctor along with your symptoms. Seek care promptly if you have high fever with chills, severe pain, or rapid worsening.

Frequently Asked Questions

It is done for fevers, suspected bacterial infections, monitoring response to treatment, and evaluating inflammatory conditions. Your doctor will decide if this test is right for your situation.

High CRP can be seen in bacterial infections, injuries, flare-ups of arthritis, and after surgery. Very high values usually prompt a search for infection. This needs clinical correlation — always discuss your report with your doctor.

A low or undetectable CRP is normal and reassuring. This needs clinical correlation — always discuss your report with your doctor.

A single value rarely tells the whole story. Results need to be read together with your symptoms, history, and other tests. Please consult your doctor for a proper interpretation.

Quick Facts

  • TestCRP
  • Short formsC-Reactive Protein
  • Sample typeBlood
  • CategoryBlood Tests

Related Terms

Inflammation Infection High

Specialists

General Medicine Orthopedics

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Disclaimer: This information is for patient education only and does not replace medical advice, diagnosis, or treatment. Always consult a qualified doctor.