Low complement C3 and C4 may be related to decreased complement synthesis, excessive depletion or loss, insufficient raw materials for synthesis, or congenital deficiency.
1. Decreased synthesis: Complement is usually synthesized by macrophages and the liver. When the body suffers from active hepatitis or cirrhosis, the ability to synthesize complement decreases, leading to a decrease in complement.
2. Excessive depletion or loss: When the body suffers from systemic lupus erythematosus, acute glomerulonephritis and other diseases, the body will have excessive depletion or loss of complement, which will lead to low complement.
3. Insufficient synthesized raw materials: when some children have malnutritional diseases, the raw materials used to synthesize complement will be insufficient, which will also lead to low complement.
4. Congenital deficiencies: Congenital complement deficiencies can also cause low complement.
Low complement C3 and C4 may also be related to other reasons, it is recommended that patients with low complement C3 and C4 go to the rheumatology and immunology department of regular hospitals and follow the doctor’s instructions for diagnosis and treatment.