The complement C4-A blood test measures the levels of the complement component 4A (C4-A) in the blood. The complement system is a part of the immune system that plays a crucial role in the body's defense against infections and the clearance of damaged or abnormal cells. Complement C4-A is a specific subtype of the complement protein C4.
Key points:
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Complement System: The complement system consists of a group of proteins that work together to enhance the immune response. Complement proteins play roles in inflammation, opsonization (marking of pathogens for destruction), and cell lysis (breaking down of cells).
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Abnormalities: Abnormalities in complement proteins, including C4-A, may be seen in conditions such as autoimmune diseases, rheumatoid arthritis, systemic lupus erythematosus (SLE), hereditary angioedema, infections, and certain kidney diseases.
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Genetic Variants: Some individuals may have genetic variations in the C4-A gene, leading to different levels of C4-A protein production. These variations are associated with autoimmune and inflammatory conditions.
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Diagnostic Marker: Testing complement C4-A levels in the blood can be used as a diagnostic marker for certain autoimmune conditions. Low levels or deficiencies in complement C4-A may suggest an increased risk or presence of autoimmune diseases.
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Monitoring Disease Activity: In some cases, complement C4-A levels may be monitored over time to assess disease activity and response to treatment in autoimmune conditions.