Causes of Alterations in C3 and C4 Levels

[Show Table Outline]

Component	Increased Levels	Decreased Levels
C3	Acute rheumatic fever Rheumatoid arthritis Early SLE Most cancers	Advanced systemic lupus erythematosus (SLE) Glomerulonephritis Renal transplant rejection Chronic active hepatitis Cirrhosis Multiple sclerosis Anemias Gram-negative septicemia Subacute bacterial endocarditis Inborn C3 deficiency Serum sickness Immune complex disease
C4	Rheumatoid spondylitis Juvenile rheumatoid arthritis Most cancers	SLE Lupus nephritis Acute poststreptococcal glomerulonephritis Chronic active hepatitis Cirrhosis Subacute bacterial endocarditis Inborn C4 deficiency Serum sickness Immune complex disease

[Table Outline]

• C3
• C4