Complement Component C4c

Test Code

CPT Codes

Preferred Specimen
1 mL serum

Minimum Volume
0.5 mL

Serum should be separated immediately from clot.

Transport Container
Plastic screw-cap vial

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 72 hours
Refrigerated: 7 days
Frozen (-20°C): 30 days
Frozen (-70°C): 90 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis • Gross lipemia • CSF • Plasma • 3.2% sodium citrate (light blue-top) tube • 3.8% sodium citrate (lt. blue-top) tube


Reference Range
16-47 mg/dL

Clinical Significance
Decreased C4 level is associated with acute systemic lupus erythematosis, glomerulonephritis, immune complex disease, cryoglobulinemia, congenital C4 deficiency and generalized autoimmune disease.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.