Complement C4

Cleveland Heartlab C, Test

CPT Code: 86160
Order Code: C2482
ABN Requirement: No
Specimen: Serum
Volume:  1.0 mL
Minimum Volume:  0.4 mL
Container: Gel-barrier tube (SST, Tiger Top)



  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 5 times immediately after draw. DO NOT SHAKE.
  3. Let tube stand in a vertical position to allow blood to clot 30 minutes.
  4. Centrifuge for 10 minutes.

Special Information: Separate serum from cells ASAP.

Transport: Store serum at 2-8°C after collection and ship the same day per packaging instructions provided with the Cleveland HeartLab shipping box.


Ambient (15-25°C): 2 days
Refrigerated (2-8°C):
2 days
Frozen (-20°C):
Not Acceptable
Deep Frozen (-70°C): 
Not Acceptable

Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits

Methodology: Turbmidimetric Immunoassay (TUI)

Turn Around Time: 4 days

Reference Range:

Age mg/dL
All Ages 13-46

Intended Use: Evaluation of autoimmune disease or complement deficiency.

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

The CPT codes provided 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 payer being billed.