Blood sedimentation and C-reactive protein are laboratory test indicators related to synovial inflammation in rheumatoid arthritis. For rheumatoid patients, blood sedimentation and C-reactive protein can directly reflect the intensity of inflammation of the chemiluminescence as well as fluctuations, and are indicators that can be used to monitor disease activity and evaluate the stability of treatment. Blood sedimentation (ESR) is a physiological characteristic of human red blood cells with suspension stability. When a hematocrit tube containing anticoagulated blood is left in a vertical position, normal red blood cells sink slowly and remain relatively stable in the plasma, despite the fact that the specific gravity of red blood cells is greater than that of plasma. The settling rate of red blood cells is usually expressed in terms of the distance they sink at the end of the first hour, and is called the erythrocyte sedimentation rate (ESR), or hematocrit. The faster the sedimentation rate, the smaller the suspension stability. The suspension stability of erythrocytes comes from the friction between the erythrocytes and the plasma impeding the sinking of the erythrocytes. The biconcave disc-shaped shape of red blood cells gives them a large surface area to volume ratio, which generates more friction and therefore sinks more slowly. If erythrocytes appear to adhere to each other more quickly with concave surfaces, this is called erythrocyte stacking. When superposition occurs, sinking is accelerated because the frictional force is reduced. The factor that determines how fast the red blood cells stack up is the change in plasma composition. Usually, an increase in the plasma content of fibrinogen, globulin, and cholesterol accelerates erythrocyte stacks and sedimentation rates; an increase in the plasma content of albumin and lecithin inhibits stacks and slows sedimentation rates. In healthy individuals, sedimentation values fluctuate within a narrow range. In many pathological conditions, the sedimentation rate increases significantly and is an indicator of the degree of disease activity. The clinical examination, usually using the Weil’s method, has a reference value of 0-15 mm/h for adult males and 0-20 mm/h for adult females. For patients with confirmed rheumatoid disease, the sedimentation value is often positively related to the inflammatory activity of the synovial membrane and also to the degree of pain and physical fatigue of clinical joint symptoms. Among the therapeutic drugs, hormones, non-steroidal anti-inflammatory drugs, immunosuppressants, and biologics can significantly reduce the hematocrit when the therapeutic effect is achieved; when the inflammation is controlled and stabilized, the hematocrit can be reduced to the normal range. Therefore, blood sedimentation has an important reference value in the diagnosis of rheumatoid arthritis, efficacy evaluation, and disease activity monitoring, and is a laboratory index that needs to be checked frequently. However, blood sedimentation is not specific to rheumatoid arthritis, and many diseases can present clinically with increased blood sedimentation. For example, common acute rheumatic fever, rheumatoid arthritis, systemic lupus erythematosus, dry syndrome, chronic nephritis, etc., especially various acute systemic and local infections, such as cold, active tuberculosis, pneumonia, etc. In addition, tissue damage and necrosis, malignant tumors, etc. can also be seen to accelerate blood sedimentation. If rheumatoid is combined with such diseases, the influencing factors need to be considered when using blood sedimentation to monitor disease activity. It should be noted that it is best to avoid the presence of systemic or local infections when we do the test, as the blood sedimentation at this time is an inaccurate reflection of rheumatoid disease activity. Some patients, in the presence of a cold, pharyngitis, etc., check the blood sedimentation, the results appear increased blood sedimentation, they are nervous: my rheumatoid how active again? In fact, it is not a rheumatoid problem at all. Factors affecting the blood sedimentation, besides the physiological and pathological conditions, environmental factors also exist, such as the temperature, the condition of anticoagulants, whether the blood sedimentation tube is vertical, etc., all may affect the blood sedimentation. Therefore, it is possible for errors to occur in the hematocrit examination, sometimes they may be more serious errors, and if necessary, they can be re-examined once. In clinical patients, especially in some patients with intermediate and advanced stages, there is often a possibility that the blood sedimentation is maintained at a certain level for a long time, suggesting a low activity state of chronic inflammation; at this time, if we want to make the blood sedimentation completely reduce to the normal range, it may be very difficult to treat, the amount of medication is heavy, and the side effects and money expenses caused are relatively large, which may not be a good choice when considered as a whole. Therefore, the idea of having low activity control in the treatment of rheumatoid is, in my personal opinion, a fact that should be accepted by patients in specific cases. Second, C-reactive protein (CRP) C-reactive protein is an acute temporal (phase) protein, also known as C-reactive egg (CRP), which can appear very quickly when inflammation appears, and is therefore a commonly used clinical laboratory test for inflammation. The normal reference value is ≤10 mg/L. C-reactive protein has the same clinical significance as hematocrit, but is not affected by red blood cells, plasma composition, lipids, or age, and is a good indicator of reaction to inflammatory infection and efficacy. It is a good indicator of inflammation, infection and healing. It increases significantly during the active phase of rheumatoid disease and parallels the increase in sedimentation, but appears earlier and disappears faster than the increase in sedimentation. If CRP is positive during the recovery process of inflammation, it indicates that there is still a possibility of sudden clinical symptoms; if CRP is positive again when it has turned negative after stopping hormone use, it indicates that the lesion movement is inherited. CRP positivity, which can also be seen in other diseases, overlaps with but is not identical to high blood sedimentation and is not a common occurrence in rheumatoid patients. In the case of colds, CRP is not usually increased in viral colds, but only in the presence of bacterial infections. It is particularly important to note that in elderly patients, increased CRP is also seen in the presence of atherosclerosis, which can also be used as an indicator of risk associated with cardiovascular disease. As disease monitoring indicators, blood sedimentation and C-reactive protein need to be checked relatively frequently and regularly, especially when the body becomes symptomatic or the symptoms worsen. By checking the blood sedimentation and C-reactive protein, we can grasp the activity of the disease and decide whether to make medication adjustments. In disease monitoring, it is usually not necessary to check both at the same time, but you can choose one and pay attention to the relevant influencing factors. In comparison, hematocrit is relatively simple and cheaper, and it is more common to do it.