What is CRP?
The abbreviation CRP stands for C-reactive protein. The protein belongs to the so-called acute phase proteins of the immune system. This is the name given to proteins that are increasingly released into the blood in the event of acute inflammation in the body and support the immune system in various ways.
CRP is formed in the liver. In the event of an infection, it binds to dead immune cells or foreign surfaces, such as bacteria and fungi, and makes them available to the immune system’s scavenger cells. In the case of a fresh inflammation, the CRP rises 10 to 1000-fold within hours and falls again quickly once the inflammation has subsided. However, the value gives no indication of where in the body the infection and/or inflammation is taking place.
When is CRP determined?
The CRP value is primarily determined in the following cases:
- Is there inflammation or an infection in the body?
- How severe is the inflammation and does it persist?
- Is the inflammation caused by viruses or bacteria?
- Is the antibiotic or anti-inflammatory therapy working?
For example, in most cases of fever or pain, the CRP is determined in order to identify inflammation as the cause.
CRP reference values
When is the CRP value elevated?
An elevated value in the blood can have many causes and should always be clarified medically.
CRP is generally elevated when there is inflammation in the body. This can be, for example, a urinary tract infection (such as cystitis), appendicitis, pneumonia or pancreatitis. CRP is also elevated in the chronic inflammatory bowel disease Crohn’s disease and in rheuamtoid arthritis (“rheumatism”).
Other possible causes of high CRP levels include acute myocardial infarction and certain tumors (such as lymphomas). The level of C-reactive protein can also be elevated after surgery.
CRP elevated: What to do?
If the CRP value is elevated, the cause of the inflammation in the body should always be clarified. Depending on the symptoms, further examinations will be carried out to determine the cause. Suitable treatment can then be initiated. If it is a bacterial infection, for example, the doctor will usually prescribe an antibiotic. In general, the concentration of CRP in the blood then drops quickly.
