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C4 component of complement in the blood
Last reviewed: 23.04.2024
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The reference values (norm) of the C4 content in blood serum are -0.2-0.5 g / l.
C4 is a component of the classical pathway of complement activation. It is synthesized in the liver. Determination of its content is important for the diagnosis of immunocomplex diseases, in which it is adsorbed on immune complexes, which leads to a decrease in the amount of free C4 in the blood.
Changes in C4 concentration for various diseases
Increase in C4 concentration
- Malignant neoplasms, sarcomas, lymphomas
Reducing the concentration of C4
- Diseases of immune complexes
- Systemic lupus erythematosus
- Glomerulonephritis
- Treatment with cytostatics and immunosuppressants
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