Inflammations are the reactions of our body to a stimulus. Sometimes they are well visible, but other times they remain hidden.
In order to ascertain whether there is an inflammation in our body, it is possible to perform some tests. For instance, the presence of C-reactive protein in the peripheral blood may be an important symptom of an inflammation. How can we measure it, and how can it be helpful? Professor Carlo Selmi, Supervisor of Rheumatology and Clinical Immunology at Humanitas, spoke about in, “Corriere Della Sera”.
C-reactive Protein
C-reactive protein (CRP) is produced in the liver and may be found in peripheral blood. Its introduction in the blood flow depends on the presence of active inflammatory processes. Thus, its levels in the blood increase significantly should there is an inflammation. It is one of the “acute-phase proteins”, such as ESR, that is the erythrocyte sedimentation rate.
If you suspect having an inflammation or suffering from an infection, you may ask for a simple blood test in order to assess your blood C-reactive protein levels.
C-reactive protein levels may confirm or negate the presence of an inflammation, but they cannot tell where the inflammation is. If the exam results are positive, the inflammation could depend on many diseases (tumours, tuberculosis, chronic inflammatory bowel diseases, pneumococcus pneumonia, systemic lupus erythematosus, rheumatoid arthritis). It is necessary to read the results of the test in the light of the disease your doctor suspects you have.
What is the Purpose of the test?
If the cause of the inflammation is known, such as an autoimmune disease characterized by chronic inflammation, the measurement of C-reactive protein may be useful to evaluate the relapse or quiet phase of the disease. This way we can verify whether the therapy is working and eventually making it possible to redefine it. The test may also be useful to understand whether a patient with an infection is recovering.
On average, reference values for CRP are lower than 5-10 mg/l, or 0.5-1 mg/dl.
However, we have to keep into consideration that some inflammatory diseases, even when they are active, do not determine high CRP values. Also, that the severity of the inflammation is not directly linked to the CRP score. Moreover, high C-reactive protein levels may also be recorded in pregnant women, in women who take contraceptives or in women getting hormone replacement therapy.
In Cardiology
In cardiology, we perform a high-sensitivity test for C-reactive protein, in order to assess even tiny variations in the protein. This test may be useful in the evaluation of the cardiovascular risk.
For example, atherosclerosis, that is the development of plaques on the walls of the arteries, is linked to the presence of another inflammation. And thanks to CRP we can detect it.
In general, this test is performed together with other tests for cardiovascular risk factors, such as cholesterol and triglycerides.