IGF Binding Protein-3 (IGFBP-3)

Test Code
IGFBP3


Quest Code
34458


Alias/See Also
34458
Insulin-Like Growth Factor


CPT Codes
83520

Preferred Specimen
1 mL serum


Minimum Volume
0.5 mL


Transport Temperature
Room temperature


Specimen Stability
Room temperature: 7 days
Refrigerated: 14 days
Frozen: 1 year


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis • Grossly lipemic


Methodology
Immunoassay (IA)

Setup Schedule
A.M. Sets up 5 days a week.


Reference Range
See Laboratory Report


Clinical Significance
Insulin-like growth factor binding proteins bind IGF-I and IGF-II with high affinity but do not bind insulin. Of the 6 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 acromegaly and low in hypopituitarism, and levels increase in GH-deficient children after GH administration. 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.


Performing Laboratory
Quest Diagnostics Nichols Institute
33608 Ortega Highway
San Juan Capistrano, CA 92690-6130



The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.