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Item Value
Available Stat? No
Test code C2
Performed by ARUP
Sendout? Yes
Method Quantitative Radial Immunodiffusion
Container type Gold or Red-top tube
Amount to Collect 2 mL (blood)
Sample type SERUM
Preferred volume 1 mL (serum)
Min. Volume 0.3 mL (serum)
Processing notes Aliquot and freeze. Aliquot cannot be shared with other tests. Transport to CB frozen. Order ARUP test code 0050148.
Ref Lab Rejection Criteria Non-frozen specimens. Specimens exposed to repeated freeze/thaw cycles. Specimens left to clot at refrigerated temperature.
Normal range
Synonyms C2, C2 Antigen, C2 Level, Classical Pathway
Stability After separation from cells: Ambient: 2 hours; Refrigerated: Unacceptable; Frozen: 2 weeks
Turn around times 5-10 days
Additional information Decreased C2 levels may be associated with increased susceptibility to infection (especially pneumococcal infections), systemic lupus erythematosus-like disease, rashes, arthritis, nephritis, and with C1-Esterase deficiency. Increased C2 levels are associated with the acute phase response.
CPT coding 86160
LOINC code 4484-2
Last Updated 7/26/2017 5:36:28 PM
Entry Number 1790
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