8 hours
Test Updated:
Connecting Peptide
C-Peptide Reactivity
CPR
Endogenous Insulin, Marker
Insulin C-Peptide
C PEPTIDE
CPEP
C-PEPTIDE
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Test Overview
Chemiluminescence
Evaluate residual beta cell function in patients with diabetes mellitus treated with insulin, low in instances of surreptitious injection of insulin, elevated in insulin autoimmune hypoglycemia, workup of hypoglycemia and to aid in the diagnosis of insulinoma with glucose and insulin assays.
1.0-5.2 ng/ml (fasting)
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Collect specimen in green top tube from a fasting patient. Place specimen on ice and transport to the laboratory, or centrifuge, aliquot into a plastic vial and freeze within 1 hour of collection.
Collect specimen in green top tube from a fasting patient (red top tube is acceptable). Place specimen on ice immediately after collection and keep cold until ready to aliquot. Centrifuge, aliquot plasma into a plastic vial and freeze within 1 hour of collection.