The C reactive protein has gained fame in recent years as the main indicator of inflammation in the body. The results of an analysis of the levels of this protein can help detect diseases that cause inflammation, such as infections and certain autoimmune diseases, as well as the presence of a chronic low grade inflammation. But what exactly is this protein and in what situations can it be elevated?
C-reactive protein or pcr: what is it
The C-reactive protein (CRP) is a protein synthesized by the liver whose levels increase in response to inflammation.
It is part of a group of proteins, called acute phase reactants, which increase in response to certain inflammatory proteins called cytokines (such as interleukin-6 [IL-6]), which are produced by white blood cells during inflammatory or infectious processes.
Its main function is remove dead or damaged cells (and some types of bacteria) by activating the complement system (a defense mechanism of our immune system whose main mission is to eliminate foreign pathogens).
C-reactive protein: normal values
C-reactive protein levels can be measured using a blood test when the doctor suspects inflammation. In general, CRP levels are considered normal when they are below 0.3 mg/dl (3 mg/l).
- Light lifting: between 0.3 and 1.0 mg/dl (3 to 10 mg/l).
- Moderate elevation: between 1.0 and 10.0 mg/dl (10 to 100 mg/l)
- Marked elevation: more than 10.0 mg/dl (100 mg/l).
- Severe elevation: more than 50.0 mg/dl (500 mg/l).
The analysis only shows the degree of elevation of CRP, which is indicative that there may be inflammation, but what is the cause of that inflammation.
C-reactive protein is high: causes
C-reactive protein is a marker of inflammation and its levels increase in response to inflammation in the body, but being high does not indicate a particular type of disease.
The causes of elevated C-reactive protein They can be diverse and include both specific and chronic conditions and can be infectious or non-infectious. In general:
- A slight elevation in CRP It can be detected in people with obesity, depression, diabetes, the common cold, pregnant women, gingivitis, periodontitis, sleep disorders, a sedentary lifestyle or smoking, among others.
- A moderate elevation of CRP It may be due to systemic inflammation such as rheumatoid arthritis, systemic lupus erythematosus (SLE), or other autoimmune diseases, some types of cancer, heart attack of myocardium, pancreatitiseither bronchitis.
- A marked elevation of CRP may be due to infections acute bacterial, viral infections, a systemic vasculitis or a severe trauma.
- A severe increase in CRP is usually due to acute bacterial infections.
It must be taken into account that some medications (such as NSAIDs or statins) can falsely lower CRP levels and that Women and older people tend to have higher CRP levels.
high C-reactive protein: symptoms
Symptoms of high levels of C-reactive protein can vary greatly depending on the underlying cause.
However, the symptoms of chronic inflammation They may include pain, tiredness, muscle stiffness or soreness, weakness, fever, headache, chills, nausea, loss of appetite, or insomnia, among others.
C-reactive protein and risk of cardiovascular disease
Some high levels of C-reactive protein in high-sensitivity blood testing have been linked to a increased risk of heart attack. It also appears that people who have had a heart attack are more likely to have another if their CRP is elevated (but not if their CRP is at a normal level).
In any case, still It is being studied whether high-sensitivity CRP is a useful measure for cardiac risk screening.since, as we have mentioned, it only indicates a degree of inflammation, but not its cause.
Literature:
Nehring SM, Goyal A, Patel BC. C Reactive Protein. [Updated 2023 Jul 10]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-.