Complement C4

What this laboratory test evaluates

DetailsComplement C4 is a blood protein that is part of the complement system, which supports the immune response by helping to fight infections and remove damaged cells. A C4 test is often used to help diagnose or monitor autoimmune conditions like systemic lupus erythematosus (SLE) and hereditary angioedema.

What type of sample is required for this test?Serum

Test ResourcesFor more information, please consult your healthcare provider.

Additional test information

Complement C4 is a blood protein that is part of the complement system, which supports the immune response by helping to fight infections and remove damaged cells. A C4 test is often used to help diagnose or monitor autoimmune conditions like systemic lupus erythematosus (SLE) and hereditary angioedema.

Collection and processing

• Sample type: Serum
• Fasting: No
• Estimated laboratory processing: Results should arrive 1 – 2 business days after the lab receives samples.

How Sunridge uses laboratory information

Sunridge considers the medical question, symptoms, history, medications, prior results, and whether the finding could change care before recommending testing. A laboratory result is not interpreted in isolation and does not establish a diagnosis by itself.

Before requesting this test

Availability, collection requirements, eligibility, and processing estimates can change. Sunridge reviews each request and, when appropriate, creates the order through Fullscript. Follow the current instructions supplied with the approved order.