C-Peptide
Label Mnemonic: CPEP
Epic Lab Code: LAB521
Downtime Form: A-1a General Laboratory Requisition
Chemistry
6240 RCP
356-3527
Specimen(s):
Plasma
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
5 mL whole blood in light green top tube (adults) or TWO Microtainer® devices (pediatric patients).
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
1.1-4.4 ng/mL in fasting specimens

Reference interval applies to fasting specimens. To convert to nmol/L, multiply ng/mL by 0.33.
Comments:
Fasting sample preferred.
Test Limitations:
Hemolysis: No significant interference up to an H index of 300 (approximate hemoglobin concentration: 300 mg/dL).

Lipemia: No significant interference up to an L index of 2000 (approximate triglycerides concentration: 4000 mg/dL). Note there is poor correlation between turbidity and triglyceride concentration.

Icterus: No significant interference up to an I index of 50 (approximate conjugated and unconjugated bilirubin concentration: 50 mg/dL).
Methodology:
Electrochemiluminescence Immunoassay
CPT Code:
83519