Corticosteroid Binding Globulin (CBG)

For Specimen Integrity during Extreme Weather see the “Lockbox Usage in Extreme Weather” document at the top of this page.

Test Code

CPT Codes
83520<br />

Preferred Specimen
1 mL serum

Minimum Volume
0.5 mL

Transport Container
Plastic screw-cap via

Transport Temperature

Specimen Stability
Room temperature: 4 hours
Refrigerated: 24 hours
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Received room temperature • Gross hemolysis

Immunoassay (IA)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Pan Laboratories, Irvine, CA. This assay has been validated pursuant to the CLIA regulations. It has not been cleared or approved by the U.S. Food and Drug Administration.

Setup Schedule
Set up: Wed; Report available: 3-8 days

Reference Range
1.9-4.5 mg/dL

Clinical Significance
Corticosteroid binding globulin (CBG) is a serum alpha 2 globulin-binding protein with high affinity binding for cortisol. Cortisol binds to CBG approximately 92 % of blood levels and rest of the cortisol is as free or bound to serum albumin. CBG is synthesized in liver. The level of CBG is increased during pregnancy and individuals taking contraceptive pills. Elevated levels are also observed in acute hepatitis and in inherited abnormality. Insulin inhibits the synthesis of CBG. The serum level of CBG is lower in hyper-insulinemic status, as in diabetes, PCO and obesity. Severe liver disease and malnutrition may result in low level of CBG. Quantitation of CBG in serum may be useful in assessing unexpected levels of cortisol in serum.

Performing Laboratory
Pan Laboratories, LLC
15375 Barranca Pkw, E101
Irvine, CA 92618

Last Updated: November 29, 2021

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.