Growth Hormone, 150 Minutes

Casandra

Casandra Test Code AR40522Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 2013929CPT Code 83003

Growth Hormone, 150 Minutes

Also known as: GH 150

Clinical Use

Order Test

Use

For pediatric patients, very low peak growth hormone concentrations on stimulation testing are consistent with severe growth hormone deficiency (GHD). Thresholds distinguishing normal from partial GHD have not been well established, and an inadequate response to two different provocative tests is required for the diagnosis of GHD. In adults, expected peak growth hormone concentrations depend on the stimulation test performed, as described in Endocrine Society guidelines for the evaluation and treatment of adults with GHD. For suppression testing, healthy subjects have growth hormone concentrations of less than 1 ng/mL within two hours of ingestion of a 75 or 100 gram glucose dose, while patients with acromegaly fail to show normal suppression.

Special Instructions

This Growth Hormone assay is standardized to the Recombinant Second International Standard (IS): 98/574. Growth hormone results read approximately 25 percent lower than with the previous standards (First IS: 80/505). Reference ranges have also been modified according to the assay manufacturer.

Limitations

Thresholds distinguishing normal from partial growth hormone deficiency have not been well established. For an accurate diagnosis of growth hormone deficiency, an inadequate response to two different provocative tests is required. In suppression testing, failure to achieve normal suppression indicates acromegaly.

Test Details

FDA Approved

New York Approved

Methodology

Immunoassay (CLIA)

Biomarkers

Growth Hormone

Protein

GH concentration • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Result Codes

27369-8

Result Turnaround Time

1-2 days

Specimen

Plasma

Volume

1 mL per timed specimen

Minimum Volume

0.4 mL per timed specimen

Container

Plasma Separator Tube (PST)

Collection Instructions

Allow specimen to clot completely at room temperature. Separate from cells ASAP or within 2 hours of collection. Transfer to ARUP Standard Transport Tubes.