Introduction
The CRP value is a parameter that is very often measured in everyday clinical practice. The CRP, also known as C-reactive protein, belongs to the group of so-called pentraxins. These are mostly proteins of the immune defence. It belongs to the acute-phase proteins, which are elevated primarily in inflammatory reactions of various kinds.
What is the CRP value?
The CRP is formed in the liver. A certain amount of CRP is naturally present in the blood of healthy people. The CRP is part of the immune system and plays an important role.
It is able to bind to the cell membrane of pathogens (e.g. foreign cells, germs). With the help of this binding it marks the pathogens for other cells of the immune system, such as macrophages. This enables macrophages to recognize the cells and render them harmless.
Furthermore, CRP can activate the complement system, which consists of many different proteins and also plays an important role in the immune defence. The CRP value is therefore particularly elevated when the immune system is working and activated to a particular degree. This is especially the case with inflammation.
The inflammation can be of an infectious nature, but it can also have a non-infectious cause such as an autoimmune disease. The CRP value therefore indicates that inflammatory processes take place in the body. It can be used as an early marker for inflammatory diseases such as appendicitis, diverticulitis or urinary tract infections because it increases earlier than other laboratory parameters.
In addition, the CRP value can be used to monitor the course of various diseases. A decrease of the value indicates an improvement of the inflammation, an increase rather an increase. However, the CRP value is an unspecific marker that cannot indicate where the inflammation is located.
In acute inflammation it can rise to 10 to 1000 times its initial value within a few hours. It is determined from the blood serum. A blood sample must be taken for this. Progress values that can be compared are particularly meaningful. They say more than a single absolute value.
Normal values of the CRP
CRP is also found in the blood of healthy individuals. The reference values vary from person to person. The value still depends on the measurement method and the laboratory that determined the value.
In adults, values up to approximately 10 mg/l (milligrams per liter) or 1 mg/dl (milligram per deciliter) are considered normal. This is different for newborns. Here values <0.5 mg/dl or <5mg/l are considered normal.
A value of 10-40 mg/l is considered a slight increase. Values between 40-200mg/l are to be considered a moderate increase. Above 200 mg/l one speaks of a strong increase of the CRP.
To assess the CRP value, it is always important to compare the measured value with the reference value of the respective laboratory that took the measurement. Depending on the measuring method, the reference values can vary from laboratory to laboratory. Thus there are sometimes slight fluctuations in the standard values. If your value is slightly higher and still corresponds to the standard according to the laboratory, this can be easily explained by this fact.
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