C-reactive protein (CRP)

C-reactive protein (CRP) is a pentameric protein synthesized primarily in the liver. It got its name because of the ability to react precipitation with pneumococcal C-polysaccharide (an important element of early protection against infection). CRP stimulates innate immune responses, including phagocytosis, participates in the interaction of T- and B-lymphocytes, activates the complement system according to the classical type. The level of CRP increases significantly with the development of inflammatory processes (infections, injuries, tissue necrosis, inflammatory diseases), and therefore it is attributed to the proteins of the acute phase of inflammation, among which it was described first. C-reactive protein is also associated with various chronic inflammatory processes. With inflammation, leukocytes begin to produce cytokines, the action of which enhances the synthesis of C-reactive protein, which leads to an increase in its level in the blood. CRP is characterized by the ability to bind calcium-dependent to various ligands – in particular, phosphocholine residues, but also many other ligands of internal and external origin. These include a number of phospholipids and related compounds, components of damaged cell membranes, modified and native lipoproteins, nucleoprotein particles, apoptotic cells, as well as polysaccharides and other components of the cell walls and membranes of microorganisms – bacteria, fungi, parasites. The formation of CRP complexes with components of damaged tissues or microorganisms activates the classical complement cascade, initiating opsonization, phagocytosis and lysis of pathogens, and removal of damaged cells. Under what conditions can the level of C-reactive protein increase C-reactive protein is the central protein of the acute phase. Its level correlates with the stage and severity of the disease and is used as a laboratory marker to assess the severity of inflammatory processes, monitor their dynamics, for differential diagnosis of bacterial and viral infections, select adequate treatment and monitor its effectiveness. The concentration of C-reactive protein in serum increases rapidly (in the first 6-8 hours) and significantly (20-100 times) in diseases associated with tissue damage, inflammation, infection or the development of a malignant process. With a successful recovery, its level decreases rapidly. Bacterial infections are accompanied by an increase in serum levels of C-reactive protein by more than 15 times. In severe generalized infections, burns, and sepsis, the level of C-reactive protein can reach a very high value, exceeding the norm by 60 times or more. A significant increase in the content of CRP is observed in diseases accompanied by tissue damage, for example, in myocardial infarction and acute pancreatitis. After surgical interventions, the level of C-reactive protein in serum increases in the early postoperative period, but decreases rapidly in the absence of infectious complications. An increase in the level of C-reactive protein is used as an indicator of inflammatory processes to assess the course of rheumatoid arthritis and Crohn's disease.

The interpretation of the research results contains information for the attending physician and is not a diagnosis. The information in this section cannot be used for self-diagnosis and self-medication. An accurate diagnosis is made by a doctor using both the results of this examination and the necessary information from other sources: anamnesis, results of other examinations, etc. Units of measurement: mg/l . Reference values: < 5 mg/l. Interpretation of the results of the C-reactive protein study Increased values of Inflammation, tissue necrosis, trauma. Bacterial infections (significant increase), viral infections (not always). Postoperative complications. Systemic rheumatic diseases. Graft rejection reaction. Malignant tumors.