Chapter II: Reverse Passive Agglutination Technique

CHAPTER II: REVERSE PASSIVE AGLUTINATION TECHNIQUE CRP examination Basic theory C-reactive protein (English:C-reactive protein, CRP) is a protein produced by the liver, especially when infection or inflammation occurs in the body. However, because this protein is not specific, the location or position of the organ experiencing infection or inflammation cannot be known. CRP examination has also been developed intohigh-sensitivity CRPso it can be used to predict the occurrence of heart disease in the future (Mayo and Prodia Lab, 2013). In patients suffering from autoimmunity diseases, CRP can also be produced by the body in large amounts, for example in patients with rheumatoid arthritis, lupus, or vasculitis. Measuring CRP levels is often used to monitor the patient's condition after surgery. In general, CRP concentrations will begin to increase 4-6 hours after surgery and reach their highest levels 48-72 hours after surgery. CRP levels will return to normal after 7 days post-surgery. However, if inflammation or sepsis occurs after surgery, the CRP levels in the blood will continue to increase. In conditions of active infection, CRP levels in the body can increase up to 100x the CRP levels in normal people, so CRP measurements are often used to determine whether a patient is infected or experiencing certain inflammation. When a bacterial infection or inflammation occurs, leukocytes are activated and then release cytokines into the bloodstream. Cytokines will stimulate liver cells(hepatocytes) to produce CRP. In 2003,Centers for Disease Control and Prevention(CDC) andthe American Heart Association(AHA) recommends the use of hsCRP to predict the risk of cardiovascular disease, especially for patients with acute coronary syndrome and stable coronary disease. The values used as a reference for assessing the risk of cardiovascular disease are: a)< 1 mg/L: low risk b)1-3 mg/L: intermediate risk c)> 3 mg/L: high risk d)> 10 mg/L indicates active inflammation or infection. Purpose of Examination:to detect infection, tissue damage, inflammation. Principle :reverse passive agglutination where the latex is coated with CRP antibodies and is detectedis the CRP antigen in serum with high levels, agglutination is visiblewithin 2 minutes Tools and Reagents Tool Reagent Ways of working a. Reagents and serum were incubated at room temperature b. Drip 50 µl of patient serum into the slide hole. c. Shake the latex reagent, then drop it into the hole with the dropper provided. d. Mix the drops using a stirrer to ensure all the test holes are mixed. e. Play the test slide, for 2 minutes see the agglutination that occurs. Interpretation of results a. Positive: If agglutination occurs: black slide, stir bar b. Negative: If no agglutination occurs : Latex (polysterin latex suspension) CLOSING a. Summary 1. Measuring CRP levels is often used to monitor the patient's condition after surgery. In general, CRP concentrations will begin to increase 4-6 hours after surgery and reach their highest levels 48-72 hours after surgery. CRP levels will return to normal after 7 days after surgery. 2. In conditions of active infection, CRP levels in the body can increase up to 100x the CRP levels in normal people, so CRP measurements are often used to find out whether a patient is infected or experiencing certain inflammation. b. Exercises 1. How long does it take for the CRP level to last? 2. What disease causes an increase in CRP? 3. Briefly explain the CRP procedure!