When you are healthy, your body produces only a small amount of CRP protein.
If your test result does not exceed this value, it means your result is within the normal range for healthy individuals. CRP is elevated when it exceeds the norm of 8 mg/L.
CRP rises very quickly – as early as 6-8 hours after the appearance of an inflammatory factor (e.g., infection, injury). If your test result or laboratory test result indicates CRP above 8 mg/L, it may mean:
Infections caused by viruses, such as the common cold, flu, viral respiratory tract infections, or mononucleosis (EBV), most often cause a slight elevation of CRP levels (8-40 mg/L). In other cases, the CRP protein value remains within the normal range. Viral diseases should under no circumstances be treated with antibiotics, which are used to combat bacteria and fungi.
Bacterial infections, especially those causing respiratory tract infections, are the most common cause of elevated CRP, with values exceeding 40 mg/L. In severe bacterial infections, CRP values exceed the 100 mg/L threshold.
Bacterial infections mainly include Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, and Gram-negative bacillus infections.
The cause of high CRP protein levels can also be:
A helpful diagnostic tool that quickly differentiates viral from bacterial infections is a home CRP test – you can find more on this topic here
Inflammatory bowel diseases (without a clear cause) are associated with chronic inflammation of the gastrointestinal tract and an increase in CRP. These include Crohn’s disease and ulcerative colitis.
Rheumatic diseases manifest as, among other things, joint inflammation, feverish states, muscle pain, and skin changes. These are conditions associated with inflammation of connective tissue, which can raise CRP levels from 10 mg/L to even 1000 mg/L in cases of disease exacerbation.
Atherosclerosis is a state of chronic inflammation resulting from damage to blood vessels. The process of atherosclerosis formation (atherosclerotic plaque) causes an increase in CRP values. The currently used hs-CRP test (high-sensitivity CRP test) is an indicator that allows for estimating the risk of developing atherosclerosis and vascular diseases. For the hs-CRP test, a concentration above 3 mg/L indicates a high risk of developing vascular disease.
Even with normal lipid panel results (blood lipid profile), an increase in CRP indicates an increased risk of cardiovascular diseases. An elevated CRP level in the blood means an almost 2-fold higher risk of stroke or vascular diseases and a 3-fold higher risk of heart attack.
It is believed that increased CRP production may be a result of cancer cell activity and the body’s response to the presence of cancer. Also, after a diagnosis, CRP measurements are recommended for cancer patients. The highest concentrations are observed in malignant tumors.
Injuries and surgical procedures that cause tissue disruption can lead to elevated CRP. This parameter is also used to monitor the healing process and assess the risk of postoperative or post-traumatic infections, e.g., after tooth extraction. In women, childbirth also causes an increase in blood CRP concentration.
Tissue necrosis is the death of tissues at the site of their damage, e.g., due to hypoxia, infection, or sudden exposure to very high temperatures. Elevated CRP levels are observed in conditions associated with necrosis, including:
Most often, the cause of high CRP is bacterial infections. In severe bacterial infections, CRP concentration often exceeds 100 mg/L. In some cases, it reaches values of several hundred, or even above 1000 mg/L (pneumonia – Chlamydia pneumoniae, Mycoplasma pneumoniae).
This is mainly observed in bacterial respiratory tract infections, e.g., tonsillitis (streptococci), and gastrointestinal infections (Escherichia coli, Salmonella).
Additionally, very high CRP can be a result of a very intense inflammatory process – the greater the inflammation, the higher the CRP protein level.
References:
[1] Orzędała-Koszel U., Bachanek T., Karczmarek−Borowska B.: C-reactive protein as a diagnostic factor in oral inflammatory conditions and neoplastic diseases, Dent. Med.Probl. 2005, 42, 1, 131-136.
[2] Boncler M., Luzak B., Watała C.: The significance of C-reactive protein in the pathophysiology of atherosclerosis. Postepy Hig Med Dosw. (online), 2006; 60: 538-546.
[3] Sapilak B. et al.: Assessment of the usefulness of C-reactive protein measurements by semi-quantitative and quantitative methods in the diagnosis of upper respiratory tract infections, Family Medicine & Primary Care Review 2012, 14, 3: 431–433.
Diagnostic tests for self-administration. Select a product to learn details, find out how to perform the test and make a purchase on our website
Rapid, at-home blood test for CRP protein levels (virus or bacteria)
