Adrenal Gland Hormones and Interpretation, Blood sample and Precautions

Sample
- The serum of the patient is required.
- The urine sample may be used.
- For catecholamines (Epinephrine and Norepinephrine) plasma in heparin or EDTA is needed.
- Transport this plasma on the ice and centrifuged at 4 C within 30 minutes and separate the plasma. Now freeze till the test is run.
- Urine may be collected for 24 hours. Add 6 M HCl and Refrigerate during collection.
- For Cortisol, Serum is needed. Can use heparinized plasma.
- Urine for 24 hours is collected with the addition of boric acid.
- The serum is stable for 2 days at 2 to 8 °C.
- Aldosterone test can be done on plasma (heparin, EDTA, or citrate).
- The serum can also be used.
- The patient must be upright for 2 hours before the sample is taken.
- Urine 24 hours is collected with boric acid and during collection is refrigerated.
- Estrogen can be estimated in the serum.
- The serum needs to be freeze immediately after collection.
- Urine 24 hours sample is collected with the addition of boric acid.
Precautions before performing the Adrenal gland tests
- A fasting sample is needed.
- Avoid exercise or physical activity.
- Reduce stress before performing this test.
- Avoid herbal medicines and any medication which interferes with the test.
- Avoid a nuclear scan before this test.
- THE aldosterone AM sample is higher than PM.
- Cortisol’s highest level is 8 AM and >50% less at 8 PM.
- Transport the plasma on ice to the lab.
- Centrifuge at 4 °C.
Pathophysiology
- Adrenal glands consist of:
- Adrenal medulla.
- Adrenal cortex.
- The adrenal cortex is derived from the mesoderm.
- These hormones maintain the homeostasis of the body.
- The adrenal medulla is derived from ectoderm.
- The adrenal cortex is derived from the mesoderm.
- The adrenal cortex secretes steroids hormones.
- Mineralocorticoid like aldosterone which regulates sodium and potassium.
- It promotes renal K+ excretion and increases water retention by increasing renal Na+ retention.
- Glucocorticoids like cortisol which is gluconeogenic.
- It regulates intermediary carbohydrate metabolism.
- Sex hormone-like estrogen and progesterone.
- Mineralocorticoid like aldosterone which regulates sodium and potassium.
- The adrenal medulla is a neuroendocrine gland which secretes:
- Epinephrine.
- Norepinephrine.
- Both act on the sympathetic nervous system.
- These hormones regulate the acute response of the body to external stimuli.
- Both act on the sympathetic nervous system.
- ACTH (Adrenocorticotropin hormone) from the pituitary gland stimulates the adrenal cortex.
- The pituitary gland (ACTH) is stimulated by the Hypothalamic hormone (Corticotropin-releasing factor (CRH).
- Serum ACTH level has a diurnal variation:
- The peak level is at 7 AM at about 200 pg/ml.
- ACTH level decline and the lowest level is at midnight around 100 pg/ml
- Cortisol secretions follow ACTH:
- The peak level is from 8.00 to 9.00 AM
- Cortisol inhibits the secretion of ACTH from the pituitary gland and also inhibits CRH from the hypothalamus.
Normal
- Epinephrine = <50 pg/mL
- Urine epinephrine = 0 to 20 µg/ day
- Norepinephrine = 110 to 410 pg/mL
- Urine norepinephrine = 15 to 80 µg/ day
- Dopamine = <87 pg/mL
- Urine dopamine = 65 to 400 µg/ day
- Cortisol Total
- Cord blood = 5 to 17 µg/dL
- Infants = 2 to 11 µg/dL
- Child 1 to 16 years at 8 am = 3 to 21 µg/dL
- adult 8 am = 5 to 23 µg/dL
- 4 pm = 3 to 16 µg/dL
- Urine cortisol (free) =
- Adult = 20 to 90 µg/ day or (<100 µg/day)
- Child = 2 to 27 µg/day
- Aldosterone
- Cord blood = 40 to 200 ng/dL
- Full term infant 3 days = 7 to 184 ng/dL
- Infants 1 to 12 months = 5 to 90 ng/dL
- Children 1 to 2 years = 7 to 54 ng/dL
- Children 2 to 10 years =
- Supine postion = 3 to 35 ng/dL
- Upright position = 4 to 48 ng/dL
- Adult
- Supine postion = 3 to 16 ng/dL
- Upright position = 7 to 30 ng/dL
- Estrogen Total
- Male = 20 to 80 pg/mL.
- Female
- Luteal phase = 160 to 400 pg/mL.
- Follicular phase = 60 to 200 pg/mL.
- Postmenopausal = <130 pg/mL
Lab tests for various adrenal dysfunctions:
Adrenal Hyperfunction leads to:
- Excess of Cortisol causes Cushing’s syndrome.
- Excess of Aldosterone causes Hyperaldosteronism.
- Excess of Androgens causes Virilizing syndrome.
Primary Hyperadrenalism:
- The cortisol level is raised.
- ACTH level decreases.
Primary Adrenal Insufficiency (Addison’s disease):
This is due to the diseases of the gland.
- The cortisol level is decreased.
- Serum sodium is low.
- Glucose level is decreased
- ACTH level is raised.
- Potassium, calcium, and blood urea are raised
Secondary Hypoadrenalism (secondary or tertiary Adrenal insufficiency):
This is due to external factors that lead to under activity of the glands.
- Cortisol level is decreased
- ACTH levelly is low.
Cushing’s syndrome:
- There is no diurnal variation of ACTH and it is absent.
- There is an elevated level of Cortisol, Glucose, and Sodium.
- There is a decreased Potassium level.
Adult adrenogenital syndrome:
- There is an elevated level of:
- DHEA
- Urine 17- ketosteroids
- ACTH
- There is a decreased level of:
- Cortisol
Congenital Adrenal Hyperplasia:
- There is an elevated level of:
- ACTH
- Androgens level
- Decreased level of:
- Cortisol
- Aldosterone
Primary Hyperaldosteronism (Conn’s syndrome):
- There is an elevated level of:
- Aldosterone urine and blood
- Serum sodium
- There is a decreased level of:
- Potassium
- Renin
- No response to aldosterone suppression test