The Role of CRP Blood Test in Detecting Inflammation and Infection

What is CRP blood test?

During any injury or infection, the human body responds through a process called inflammation. This can be acute or temporary and can occur outside or inside the body. C-reactive protein (CRP) is an inflammatory protein that increases up to nearly 1000-fold at locations where infection or inflammation is observed. It is synthesized majorly in liver hepatocytes but also by other cells such as macrophages, endothelial cells, lymphocytes, etc. A simple blood test can check your C-reactive protein level and can give an idea about the presence and extent of inflammation in the body. Persistently elevated expression of CRP is observed in conditions such as infection, injuries, autoimmune disorders and some cardiovascular diseases. 

Importance of hs-CRP:

Both CRP and hs-CRP measure the same molecule, but hs-CRP is different from the latter. This test is very sensitive and measures lower levels of CRP in the blood than the CRP test. Generally, hs-CRP is done predominantly to check for any cardiovascular diseases or any other heart conditions in a healthy individual. Some other cases in which hs-CRP is elevated are found in Diabetes, atherosclerosis and IBS (irritable bowel syndrome).

The hs-CRP test results with the following ranges indicate cardiovascular issues. But it can vary from lab to lab.

< 2 mg/l indicates a lower risk of cardiac issues

>2 mg/l indicates a higher risk of cardiac issues

Why CRP blood test is done?

The CRP test is majorly done:

-To check any bacterial, viral or fungal infections 

-To check for any chronic inflammatory diseases

-To check for any autoimmune diseases, such as Rheumatoid arthritis. 

-To check for cardiovascular issuessuch as heart attacks.

-To check any allergic reactions

CRP test can’t alone diagnose a condition. It needs further additional tests such as ESR (Erythrocyte sedimentation rate) to show inflammation or infection in the body. Both are non-specific markers for inflammation but can give an idea about what’s going inside the body.

When is the CRP test required?

CRP itself does not cause symptoms; rather, it is a sign of an underlying issue. CRP test is recommended by doctors for individuals with symptoms such as in case of infections which include Fever, nausea, Abnormal heart rates, any breathing issues or symptoms related to internal inflammation such as rheumatoid arthritis and unexplained tiredness etc.

The CRP blood levels range varies with respect to other labs and may have slightly different guidelines, which means less elevation in CRP levels means nothing. Generally, under 3 mg/dl is considered normal, anything above 10.0 mg/dl will typically indicate an underlying inflammatory issue. Reference ranges often vary between labs and need to be considered accordingly.

CRP range depending on the conditions:

<1 mg/dL: Normal 

>1-10 mg/dL: Moderate elevation occurs in bodily inflammation in autoimmune conditions.

>10 mg/dL: Marked elevation occurs in bacterial and viral infections, major trauma.

>50 mg/dL: Severe Elevation majorly occurs in acute bacterial infections.

Conclusion:

High Levels of CRP often indicate a serious health condition. The need to address elevated CRP includes antibiotics, anti-inflammatory drugs, change in lifestyle and following a healthy diet with regular exercise can aid in reducing inflammation. CRP test may be recommended by doctors depending on the symptoms with other tests to check for the health condition, monitor inflammation or any heart diseases. Finally, treatment for elevated CRP depends on the cause of condition and other tests.