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C4, Serum (8000100173)
Test Mnemonic:


Specimen Requirements:

7 mL of blood in SST or red-topped vacutainer tube.  

Minimum Volume:



Delivered to Sample Management within 2 hours of collection.

Specimen Preparation:

Allow specimen to clot completely at room temperature. Centrifuge to separate serum from cells within 2 hours of collection. Transfer serum from collection tube to labeled plastic transport tube. 


Room temperature for ≤ 6 hours; Refrigerator for ≤ 24 hours; Frozen for ≤ 7 days. (Avoid repeated freeze/thaw cycles).         

Causes for Rejection:

Incomplete and/or incorrect sample identification, improper storage/transport and gross hemolysis or lipemia.                                

Reference Range:

By report (reports may vary based on instrumentation, patient age and sex).

Turnaround Time:

Monday - Sunday: 7 am - 3:00 pm




Special Chemistry;    

Monday - Sunday: 7 am - 3:00 pm


CPT 4 Code:



Director approval required for STAT requests.

When ordering tests for which Medicare or Medicaid reimbursement will be sought, physicians should only order tests that are medically necessary for the diagnosis or treatment of the patient. Components of the organ or disease panels may be ordered individually. The diagnostic information must substantiate all tests ordered and must be in the form of an ICD-10 code or its verbal equivalent.
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