C-Peptide Urine
Test Mnemonic
UCPEP
CPT Codes
- 84681 - QTY (1)
Performing Laboratory
ARUP
FDA Category
In Vitro Diagnostic
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Urine, 24-hour (well-mixed) | Clean container | Refrigerate during collection. | Frozen |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 0.5 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 2 hours |
| Refrigerated | 1 day |
| Frozen | 1 month |
Days Performed
Sun - Sat
Turnaround Time
2 - 3 days
Methodology
| Name | Description |
|---|---|
| Chemiluminescence Immunoassay (CLIA) |
Reference Range
| C-Peptide Urine | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | 14-156 | ug/day |
Special Info
Indicate total volume on requisition. Random urines are acceptable, but have no reference ranges.
Clinical Info
Used in assessment of beta-cell activity in insulin-treated diabetes mellitus. An increase in insulin requirement is well correlated with a decrease in C-peptide level in serum and urine. Progressive exhaustion of beta reserves, as monitored by C-peptide level, can be used to measure metabolic stability or 'brittleness' of diabetes mellitus. In transient diabetes mellitus, the return of C-peptide level to within the normal range could provide evidence of remission. Measurement of C-peptide can be used for the diagnosis of insulinoma. Following exogenous insulin challenge, insulin secretion (monitored by C-peptide level) is suppressed in normal subjects. In patients with an insulin-secreting tumor or cancer no significant suppression of C-peptide level is found.