Insulin-like Growth Factor 1 (IGF-1), Pediatric With Z Score (Endocrine Sciences)
Use
IGF-1 measurements can be useful when evaluating patients of gestational age1 who are suspected of being (1) growth hormone-deficient2 or (2) acromegalic.3
Special Instructions
Patient gender and date of birth must be provided to calculate a z score, and z scores will not be calculated for patients younger than three years or older than 18 years. To avoid delays in turnaround time when requesting multiple tests on frozen specimens, please submit separate frozen specimens for each test requested.
Limitations
Plasma specimens may produce falsely elevated or decreased results. The IGF-1 reference intervals by pubertal Tanner stages reflect ranges and means based on asymmetric curves. Z scores are calculated based on these curves using transformed data. Z scores will not be calculated for patients younger than three years or older than 18 years, which restricts the test's application to certain age groups.
Methodology
Immunoassay (RIA)
Biomarkers
LOINC Codes
- 503660
- 2484-4
- 73561-3
Result Turnaround Time
6-12 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.1 mL
Container
Red-top tube or gel-barrier tube
Collection Instructions
Serum must be separated from cells within 45 minutes of venipuncture. Send serum in a plastic transport tube. Transfer specimen to a plastic transport tube before freezing.
Storage Instructions
Freeze. Stable for two days at room temperature or refrigerated. Stable for two years frozen.
Causes for Rejection
Specimen not serum
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 2 days |
| Refrigerated | 2 days |
| Frozen | 2 years |