Complement Component C4a, Plasma

What this laboratory test evaluates

DetailsComplement Component C4a, Plasma – During activation of the classical or lectin pathway of complement, C4 is cleaved into C4a and C4b. C4a is rapidly cleaved to the more stable form C4a-des-arg. Even if total C3 and C4 levels are not low (because of increased production by the liver during acute inflammation), elevated levels of C4a-des-arg indicate recent complement pathway activation.

What type of sample is required for this test?2 mL frozen plasma collected in an EDTA (lavender-top) tube, submitted in a protease inhibitor transport tube

Test ResourcesFor more information, please consult your healthcare provider.

Additional test information

Complement Component C4a, Plasma – During activation of the classical or lectin pathway of complement, C4 is cleaved into C4a and C4b. C4a is rapidly cleaved to the more stable form C4a-des-arg. Even if total C3 and C4 levels are not low (because of increased production by the liver during acute inflammation), elevated levels of C4a-des-arg indicate recent complement pathway activation.

Collection and processing

• Sample type: Plasma
• Fasting: No
• Estimated laboratory processing: Results should be available in 2 – 5 business days after the sample is collected

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.