C-reactive protein, mass concentration (serum/plasma)

What Is CRP Used For?

CRP is primarily used to detect and monitor inflammation in the body. It can help identify infections (such as bacterial infections), autoimmune diseases (like rheumatoid arthritis), heart disease risk, and other inflammatory conditions. Some doctors may also use it to assess how well treatment is working for certain conditions.

When Might You Need This Test?

Your healthcare provider may order a CRP test if you have symptoms of infection, chronic inflammation, or if you’re at higher risk for heart disease. It’s also sometimes used during pregnancy to check for complications or to monitor conditions like lupus or other autoimmune disorders.

How Is the Test Performed?

A blood sample is taken from a vein in your arm. The sample is sent to a lab, where it’s analyzed to measure CRP levels. The test usually takes a few hours to complete, and results are reported in milligrams per liter (mg/L) or micrograms per milliliter (µg/mL).

What Do Results Mean?

CRP levels can vary widely depending on your health, age, and other factors. Higher than normal levels often signal inflammation, but they don’t always indicate a specific cause. Your doctor will interpret results in the context of your medical history and symptoms.