Endocrine Diagnostic Tests
- 24 Hour Urine Collection
- Arginine/ GHRH Growth Hormone Stimulation Test
- Arginine Growth Hormone Stimulation Test
- ACTH (cortisol) stimulation Test
- Dexamethasone Suppression / CRH Stimulation Test
- Inferior Petrosal Sinus Sampling
- Insulin Tolerance Test
- Oral Glucose Growth Hormone Suppression Test
- Salivary Cortisol Samples
- Water Deprivation Test
Arginine/ GHRH Stimulation Test
Indication
This test determines whether the pituitary gland produces normal amounts of growth hormone.
Preparation
NPO for at least 8 hours prior to test
Procedure
1. Baseline growth hormone and somatomedin-C levels.
2. Inject 0.5 g/kg Arginine over 30 miuntes intravenously.
3. Inject 1 mcg GHRH over 1 minute intravenously.
4. Serum growth hormone levels at 15, 30, 45, 60 minutes
Interpretation
A growth hormone level greater than 8 ng/ml is a normal response. A growth hormone level less than 8 ng/ml is an abnormal response suggesting growth hormone deficiency.