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IGF-1, insulin-like growth factor 1

Lab Section:  Sendout Reference  
Lab Location:  Sendout
Reference Lab: Quest 
Test ID: LAB3145 
Methodology: Liquid Chromatography/Mass Spectrometry (LC/MS)
Schedule: Daily
Reported: 7 days
Specimen Requirements:  Collection: 3.0 mL Blood in a Gold Top Tube.
Pediatric volume: 1 mL.
Collect blood in a red-top or SST vacutainer. For red-top vacutainers, allow blood to clot (10-15 minutes) at room temperature. Separate serum from cells and refrigerate. If sample collected in glass collection tube, transfer to plastic container.
Transport: Refrigerated (cold packs).
Unacceptable conditions: Gross hemolysis Gross lipemia Received in glass tube Received room temperature Grossly icteric
Stability: Room temperature: 48 hours Refrigerated: 5 days Frozen: 28 days


Clinical Indications: Insulin-like growth factor I (IGF-I, or somatomedin C), a protein involved in stimulating somatic growth, is regulated principally by growth hormone (GH) and nutritional intake. IGF-I is transported in serum by several proteins; this helps maintain relatively high IGF-I plasma levels and minimizes fluctuations in serum IGF-I concentrations. Measuring IGF-I is useful in several growth-related disorders. Dwarfism caused by deficiency of growth hormone (hypopituitarism) results in decreased serum levels of IGF-I, while acromegaly (growth hormone excess) results in elevated levels of IGF-I. IGF-I measurements are also helpful in assessing nutritional status; levels are reduced in undernutrition and restored with a proper diet.

Reference Interval:  See patient report or consult reference laboratory website.
CPT Code(s): 84305
Last Changed: 11/11/2016 11:21:16
Last Reviewed: 12/22/2016 01:50:58