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IGF binding protein-3

Lab Section:  Sendout Reference  
Lab Location:  Sendout
Reference Lab: Quest 
Test ID: LAB3144 
Synonyms: IGFBP-3 • Insulin-like growth factor binding protein 3
Methodology: Immunoassay (IA)
Schedule: Monday-Friday
Reported: 7 days
Specimen Requirements:  Collection: 3.0 mL Blood in a Gold Top Tube.
Pediatric volume: 1 mL.
Plastic screw-cap vial
Transport: Room temperature.
Unacceptable conditions: Gross hemolysis Gross lipemia Plasma
Stability: Room temperature: 7 days; Refrigerated: 14 days; Frozen: 1 year


Clinical Indications: Insulin-like growth factor binding proteins bind IGF-I and IGF-II with high affinity but do not bind insulin. Of the six distinct IGF binding proteins structurally characterized at this time, IGFBP-3 has been shown to be the major carrier of the IGFs, transporting approximately 95% of circulating IGF-I and IGF-II. IGFBP-3 is growth hormone (GH) responsive. Thus, levels are high in cromegaly and low in hypopituitarism, and levels increase in GH-deficient children after GH administration. Thus, both assays and the ratios of IGF-I/IGFBP-2 and IGFBP-2/IGFBP-3 are useful as markers of GH action and for discriminating between growth hormone deficiency and short stature due to other etiologies in children. Other causes of short stature that result in reduced IGFBP-3 levels include poorly controlled diabetes. The IGFBP-3 assay is useful in assessing nutritional status, since IGFBP-3 decreases during both caloric and protein restriction.

Reference Interval:  See patient report or consult reference laboratory website.
CPT Code(s): 83519
Last Changed: 11/11/2016 11:18:11
Last Reviewed: 12/22/2016 01:49:58