Acute phase protein (Acute Phase Reactants)
- Acute phase protein is raised in the inflammatory conditions.
- There may be increased in acute phase proteins called positive acute phase protein.
- In the case of a decrease in the acute phase, protein is called negative phase protein.
- The acute phase proteins are protein whose concentration increases in the plasma and after the disease episode over then it decreases and may become normal
Complement C3 and C4 (Complements)
- The venous blood of the patient is needed to prepare the serum.
- This can be done on EDTA plasma.
- C3 is very unstable at room temperature.
- It is advised to do the test immediately.
- Or freeze at -70 °C.
- Advised to diagnose angioedema.
- To monitor:
- The patient with systemic lupus erythematosus nephritis.
- In post-streptococcal nephritis.
- In membranoproliferative nephritis.
- Complements are a group of globulin proteins.
- These are heat labile plasma proteins.
- These consists of at least 14 protein which has a biological function in the immune system.
- These acts as an enzyme.
- This will help in the immunologic response and inflammation.
- They help in the chemotaxis and activation of the WBCs.
- The complement activation leads to lysis of the antigen or the bacteria.
- Complement is the biological amplifier.
- First, there is activation of the few molecules of C1q.
- In the next stage more and more molecules are activated.
- In the final stage, there are thousands of molecules.
- The classical pathway is activated by the C1 and ultimately there is activation of C1 to C9.
- In the alternate pathway, there is a bypass of the C1q and direct activation of C3.
- The alternate pathway may be activated by IgA.
- This is activated in the absence of the antibody.
- Polysaccharides of the bacterial cell wall can activate C3 and leads destruction of the bacteria.
- In the case of antigen and antibody complexes, the complement is consumed which leads to decreased level of compliments.
- Cord serum = 65 to 111.8 mg/dL
- Children = 86.6 to 135.8 mg/dL
- Adult = 83 to 177 mg/dL
- Cord serum = 13.7 to 44.9 mg/dL
- one month = 27.5 to47.3 mg/dL
- 6 months = 30.5 to 58.7 mg/dL
- Adult = 28.7 to 67.5 mg/dL
The decreased level of complement (C1 to C9) is seen in:
- Congenital as seen in angioedema.
- Autoimmune diseases like SLE, serum sickness, rheumatoid arthritis, Sjogren's syndrome, and lupus nephritis.
- Acute kidney transplant rejection.
- In case septicemia (sepsis).
The increased level of complements (C1 to C9) is seen in:
- Acute rheumatic fever.
- Ulcerative colitis.
- Acute myocardial infarction.
- Malignant tumors.
|Acute phase proteins
Table showing Positive and Negative acute phase protein
|Positive acute phase proteins
||Negative acute phase proteins
|Complement (C 3, 4)
Possible References Used
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