Supersensitive CRP is part of the non-specific immune mechanism. In the presence of calcium ions, it can bind to phosphatidic acid choline on the membrane, and can also bind to chromatin to activate the classic pathway of complement, enhancing the phagocytosis of leukocytes. Stimulate the activation of lymphocytes or monocytes/macrophages and play a conditioning role.
It increases during microbial invasion, tissue damage, immune response, and inflammatory processes. It appears quickly and has a short half-life. It changes with the inflammatory process. The level of CRP is related to the occurrence and severity of inflammation. However, CRP cannot pass through the placenta, so the content in normal newborn serum is very small.
Extended information:
1: The role of hypersensitive CRP:
hs-CRP is mainly used to diagnose and predict the occurrence and development of cardiovascular events; new life Screening, monitoring, evaluation and drug efficacy judgment of bacterial/viral infections and various inflammatory processes in infants and young children.
Measurement of hs-CRP level concentration can be used as a monitoring indicator to determine the occurrence and prognosis of acute coronary syndrome. In addition, because the basic value of infants and young children is lower than that of adults, the inflammation levels of newborns and infants must be reflected by hs-CRP.
High-sensitivity CRP plays an increasingly important role in the diagnosis and prediction of coronary heart disease, stroke, peripheral vascular embolism and other diseases, and is even considered the "gold standard" for cardiovascular disease risk assessment.
Two: Clinical application of high-sensitivity CRP
1. High-sensitivity C-reactive protein and brain injury?
Serum high-sensitivity C reaction after brain injury Protein levels increased to varying degrees, and the more serious the injury, the more obvious the increase. This shows that high-sensitivity C-reactive protein is not only a disease marker, but also participates in the pathogenesis of traumatic diseases. The more severe the trauma, the faster the liver cells synthesize high-sensitivity C-reactive protein under the induction of IL-6 and other cytokines. faster and released into the bloodstream. The more serious the injury, the slower the rate of decline in high-sensitivity C-reactive protein. It can be seen that the increase amplitude and duration of high-sensitivity C-reactive protein after craniocerebral injury are ideal indicators to reflect the severity of craniocerebral injury and observe the efficacy, and are of great significance in judging the severity of the injury and predicting the prognosis
2 , High-sensitivity C-reactive protein and atherosclerosis?
Recent studies have shown that high-sensitivity C-reactive protein is located in atherosclerotic plaques and has the effect of regulating monocyte aggregation. High-sensitivity C-reactive protein The protein is a complement activator. It is present in early atherosclerotic lesions together with the membrane attack complex. It can stimulate the production of tissue factor, and the accumulated high-sensitivity C-reactive protein can activate complement. Tissue factor primarily initiates the blood clotting process. Chronic trace amounts of inflammatory factors activate complement and cause lipid deposition on the blood vessel wall. Through infiltration and aggregation, it causes vascular damage and leads to atherosclerosis.
3. High-sensitivity C-reactive protein and coronary heart disease?
The American Physician Health Study (PHS) shows that patients with high-sensitivity C-reactive protein in the highest group have a higher risk of future disease attacks The risk of myocardial infarction (MI) in the future is 3 times that of normal people, and the risk of peripheral arterial disease is 4 times that of normal people. European MONICA's Augsburg study showed that people in the highest group with high high-sensitivity C-reactive protein have a risk of developing coronary artery disease that is 2.6 times higher than normal people in the future. ?
Plasma high-sensitivity C-reactive protein levels in patients with coronary heart disease are closely related to coronary artery disease, reflecting the degree of myocardial damage. Therefore, this indicator helps to make accurate judgments on the occurrence, development and prognosis of coronary heart disease, and has important clinical significance. There is no direct correlation between serum high-sensitivity C-reactive protein level and coronary artery stenosis score. The serum high-sensitivity C-reactive protein level in patients with coronary heart disease is related to the stability of atherosclerotic plaques, but has nothing to do with the degree of coronary artery stenosis.
① CRPH <1.0mmol/L, cardiovascular disease is assessed as low risk;
② CRPH 1.0-3.0mmol/L, cardiovascular disease is assessed as moderate risk, Anti-inflammatory treatment is recommended;
③ CRPH >3.0mmol/L, cardiovascular disease is assessed as high risk. Combination anti-inflammatory and antithrombotic treatment is recommended.
4. High-sensitivity C-reactive protein and cerebrovascular disease?
Inflammatory reaction promotes the occurrence and development of atherosclerosis. Serum high-sensitivity C-reactive protein reflects atherosclerosis. A sensitive indicator of the patient's clinical condition. High-sensitivity C-reactive protein value was correlated with cerebrovascular disease risk factors (age, body mass index, abdominal circumference, systolic blood pressure, diastolic blood pressure, fasting blood glucose, triacylglycerol, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol). There was a significant correlation; the high-sensitivity C-reactive protein value was significantly positively correlated with systolic blood pressure, fasting blood glucose, triacylglycerol, and total cholesterol. High-sensitivity C-reactive protein is significantly related to the prevalence of acute stroke; blood pressure, fasting blood glucose and blood lipids are the main independent factors affecting high-sensitivity C-reactive protein. Early monitoring of high-sensitivity C-reactive protein has warning significance for ischemic stroke caused by carotid atherosclerosis.
Three: Reasons for high hypersensitive CRP
The most common cause of elevated CRP in children is infection. It is generally believed that elevated CRP indicates bacterial infection, and Gram-negative bacterial infection. Higher than Gram-positive bacterial infections; however, CRP can also be elevated in viral, mycoplasma, and fungal infections, but the latter three are often not as elevated as bacterial infections.
When hs-CRP > 20 mg/L and white blood cells >10×109/L, bacterial infection is generally considered to be a possibility;
When the disease course exceeds 24 hours, hs- When CRP is still <5 mg/L and white blood cells <10×109/L, viral infection is likely;
For children between the above two conditions, bacterial, mycoplasma, and fungal infections should be considered All are possible.
But the following three points need to be noted:
(1) CRP is often elevated in hand, foot and mouth disease and herpangina. Elevated CRP can indicate severe cases, but it cannot yet To distinguish whether there is a bacterial infection, joint detection of PCT (specificity 98, sensitivity 94) is needed to help identify it.
(2) CRP can also be significantly elevated in children with coronavirus enteritis when they have fever, vomiting, and dehydration, but most children can quickly return to normal without the use of antibiotics after the acute phase.
(3) When CRP is significantly elevated and anti-infective treatment is not effective, you need to be alert to autoimmune diseases, such as Kawasaki disease, inflammatory bowel disease, juvenile rheumatoid arthritis, SLE and other diseases. Usually It indicates disease activity, but due to its poor specificity, it can only provide suspicious clues in the direction of diagnosis.