Complement Component 2
Also known as: C2
Use
The Complement Component 2 (C2) test is used as a follow-up to complement activity screening when the CH50 is low or absent and the AH50 is normal, and high suspicion remains for complement deficiency. Decreased C2 levels are associated with increased susceptibility to infection, including pneumococcal infections, systemic lupus erythematosus-like diseases, rashes, arthritis, nephritis, and C1-Esterase deficiency. Increased C2 levels are associated with the acute phase response.
Special Instructions
The test is New York state approved. Critical handling is required to ensure specimen viability, as it must be submitted frozen. Separate specimens must be submitted when multiple tests are ordered to avoid specimen rejection.
Limitations
The test has not been cleared or approved by the US Food and Drug Administration. Results may be affected if specimens are exposed to repeated freeze/thaw cycles or if they are not handled as specified. Refrigerated specimens or those not immediately separated from cells can provide inaccurate results.
New York Approved
Methodology
Immunoassay (Other)
Biomarkers
LOINC Codes
- 4484-2
Result Turnaround Time
5-10 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.3 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Allow specimen to clot for one hour at room temperature. Separate serum from cells ASAP or within 2 hours of collection. Freeze immediately.
Storage Instructions
CRITICAL FROZEN.
Causes for Rejection
Non-frozen specimens. Specimens exposed to repeated freeze/thaw cycles. Specimens left to clot at refrigerated temperature.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 2 hours |
| Refrigerated | Unacceptable |
| Frozen | 2 weeks |