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Also known as: C1; C1q; C2; C3; C4; CH50; CH100 (among others)
Formal name: Complement Activity; Complement Component; Total Complement; Total Hemolytic Complement Activity

At a Glance

Why Get Tested?

To determine whether deficiencies or abnormalities in complement system proteins are contributing to increased infections or increased autoimmune activity; to help monitor the activity and treatment of autoimmune diseases and immune complex-related diseases

When to Get Tested?

When you have recurrent microbial (usually bacterial) infections, unexplained inflammation or edema, or symptoms related to an autoimmune disorder; periodically to help monitor a known acute or chronic condition that affects the complement system

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?