COMPLEMENTS (C3 & C4)

• C3 Adult-0.9- 1.8 g/l
• C4 Adult-0.1 -0.4 g/l

• The complement system is a group of proteins found in the blood and tissues and play an important role in host defence against infectious agents and inflammatory process. Complement tests measure the amount or activity of complement proteins in blood
• The Principal role of complement system is to help identify, destroy and remove foreign pathogens like bacteria and viruses as well as damaged cells and proteins
• The complement system is part of the body’s innate immune system. There are nine primary complement proteins that are designated C1 - C9. These components in addition to the remaining proteins work together in a cascade like approach and form protein complexes that respond to infections, non self tissues, dead cell debris or inflammation
• The complement cascade consists of three separate pathways. The end result of all tree pathways is the formation of Membrane attack complex. Complement tests, mostly C3 and C4 are used to determine whether deficiencies or abnormalities in the complement system is causing or contributing to a person’s disease or condition
• Complement testing helps to diagnose the cause of recurrent microbial infections, angioedema, or inflammation
• Complement testing helps to help diagnose and monitor the activity and treatment of acute or chronic auto immune diseases such as lupus and Rheumatoid arthritis
• Complement testing helps to monitor immune complex related diseases such as glomerulo nephritis, serum sickness and vasculitis

Elevated C3 & C4

• Ulcerative colitis
• Acute phase response

Decreased c3 & C4

• Hereditary angioedema
• Cirrhosis
• Glomerulonephritis
• Hepatitis
• Lupus nephritis
• Malnutrition
• Renal transplant rejection
• SLE
• Fungal infections
• Malaria