Examinations
Examinations
Complement C4 is a crucial protein in the complement system, which plays an essential role in immune defense and inflammation. It is primarily produced in the liver, lungs, and bones and is activated through the classical pathway of the complement system.
Clinical Significance
- C4 is involved in phagocytosis, the process by which immune cells engulf and break down foreign substances and bacteria.
- It enhances vascular permeability, allowing immune cells to reach infected or damaged tissues.
- C4 deficiency is strongly associated with systemic lupus erythematosus (SLE) and other immune complex diseases.
- Take the test at least 2 hours after the last meal.
- Avoid smoking for 1 hour before the test.
- Avoid physical and emotional stress for 1 hour before the test.
- Suspected Scarlet Fever (Scarlatina)
- Diagnosis and monitoring of autoimmune diseases (e.g., lupus, rheumatoid arthritis)
- Monitoring autoimmune disease treatment
- Suspected inflammatory and secondary bacterial infections
- Evaluation of potential malignancies
Elevated C4 Levels May Indicate:
- Malignancies (sarcoma, lymphoma, other cancers)
- Juvenile rheumatoid arthritis (JRA)
Decreased C4 Levels May Indicate:
- Hereditary C4 deficiency
- Systemic lupus erythematosus (SLE)
- Chronic bronchitis
- Chronic active hepatitis
- Immune complex diseases
- Glomerulonephritis