Sign in →

Test Code Billings Clinic: 4089 C3 (Third Component of Complement), Serum

Additional Codes

Ordering Mnemonic
MayoAccess: BCL369

Performing Laboratory

Billings Clinic Laboratory: Chemistry

Useful For

  • Assessing disease activity in systemic lupus erythematosus (SLE)
  • Investigating an undetectable total complement (CH50) level



Specimen Requirements

Submit one of the specimens below:



  • Draw blood in a lithium heparin tube(s).
  • Spin down and send 1 mL of plasma frozen in plastic vial.


  • Draw blood in a serum gel tube(s).
  • Spin down and send 1 mL of serum frozen in plastic vial.



Specimen Type Temperature Time
Serum, Plasma Refrigerated 7 days
  Frozen (preferred) 3 months


Reject Due To

  • Lipemia

Reference Values

90-180 mg/dL

Day(s) Test Set Up


Test Classification and CPT Coding

86160 - Complement; antigen, each component

LOINC Code Information

Reporting Name LOINC Code
Comp, C3 4485-9