Complement C4 at Test Zone Diagnostic Center

The Complement C4 test measures the amount of C4 protein, another key part of the complement system. Like C3, it helps the body fight infection. Low levels of C4 are often seen in autoimmune conditions, particularly systemic lupus erythematosus (SLE), and can be used to monitor disease activity.

Key Benefits:

• Helps diagnose and monitor autoimmune disorders, especially lupus.

• Provides information about complement system activity.

• Used alongside C3 for a more complete immune system evaluation.