Adrenal Gland Hormones and Interpretation

Adrenal gland hormones are biologically active substances produced by the adrenal glands, which are located atop the kidneys. These hormones include cortisol, aldosterone, adrenaline (epinephrine), and androgens, each playing crucial roles in regulating metabolism, immune response, blood pressure, stress response, and sexual development. Cortisol helps in glucose metabolism and reducing inflammation; aldosterone regulates sodium and potassium balance; adrenaline is vital for the fight-or-flight response; and androgens contribute to the development of male characteristics and reproductive activity. Collectively, these hormones ensure the body maintains homeostasis and responds effectively to internal and external stressors.

What hormones are produced by the adrenal glands?

Hormones produced by the adrenal glands can be broadly classified into three main categories: corticosteroids, catecholamines, and androgens.

Corticosteroids

These hormones are produced in the cortex of the adrenal glands and are divided into two main types: glucocorticoids and mineralocorticoids.

Glucocorticoids

1. Cortisol: Also known as hydrocortisone, cortisol is crucial for regulating metabolism, reducing inflammation, and controlling the body's stress response. It helps manage how the body uses carbohydrates, fats, and proteins and maintains blood pressure and cardiovascular function.

Mineralocorticoids

1. Aldosterone: This hormone plays a key role in regulating sodium and potassium levels in the blood, which in turn helps control blood pressure and the balance of fluids in the body.

Catecholamines

These hormones are produced in the medulla of the adrenal glands.

1. Epinephrine (Adrenaline): Epinephrine increases heart rate, expands air passages in the lungs, and helps in the fight-or-flight response by providing a quick burst of energy.
2. Norepinephrine (Noradrenaline): Norepinephrine works alongside epinephrine in responding to stress but also has a significant role in increasing blood pressure by constricting blood vessels.

Androgens

These are male sex hormones produced in small amounts by the adrenal cortex.

1. DHEA (Dehydroepiandrosterone): DHEA serves as a precursor to other sex hormones, including testosterone and estrogen. It has roles in developing secondary sexual characteristics and maintaining muscle mass and overall vitality.

Summary of Adrenal Gland Hormones

Hormone	Category	Function
Cortisol	Glucocorticoid	Regulates metabolism, reduces inflammation, manages stress
Aldosterone	Mineralocorticoid	Regulates sodium and potassium levels, controls blood pressure
Epinephrine	Catecholamine	Increases heart rate, expands airways, fight-or-flight response
Norepinephrine	Catecholamine	Increases blood pressure, aids in stress response
DHEA	Androgen	Precursor to sex hormones, supports muscle mass, vitality

Why is this test performed?

This hormonal assessment is conducted under various clinical conditions, such as Hyperaldosteronism, Cushing's Syndrome, and Virilizing Syndrome.

Laboratory Tests for Adrenal Abnormalities

Primary Adrenal Insufficiency (Addison's Disease)

This condition arises from intrinsic gland pathology.

• Serum sodium levels are reduced.
• Cortisol levels are decreased.
• Glucose levels are decreased.
• ACTH levels are elevated.
• Potassium, calcium, and blood urea levels are increased.

Adrenal Hyperfunction

• Increased aldosterone levels result in Hyperaldosteronism.
• Elevated cortisol levels cause Cushing's Syndrome.
• Enhanced androgen levels lead to Virilizing Syndrome.

Primary Hyperadrenalism

• Cortisol levels are elevated.
• ACTH levels are decreased.

Secondary Hypoadrenalism (Secondary or Tertiary Adrenal Insufficiency)

This condition results from external factors causing gland underactivity.

• ACTH levels are decreased.
• Cortisol levels are reduced.

Adult Adrenogenital Syndrome

• Elevated levels of:
  1. Urine 17-ketosteroids
  2. DHEA
  3. ACTH
• Reduced levels of:
  1. Cortisol

Congenital Adrenal Hyperplasia

• Decreased levels of:
  1. Cortisol
  2. Aldosterone
• Elevated levels of:
  1. ACTH
  2. Androgens

Primary Hyperaldosteronism (Conn's Syndrome)

• Decreased levels of:
  1. Renin
  2. Potassium
  3. No response to aldosterone suppression test
• Elevated levels of:
  1. Serum sodium
  2. Aldosterone in urine and blood

Cushing's Syndrome

• Elevated levels of glucose, sodium, and cortisol.
• Absence of diurnal variation in ACTH levels.
• Decreased potassium levels.

Sample Collection

To assess adrenal gland hormones, a patient's serum is required. Additionally, a 24-hour urine sample is collected along with a blood sample.

For Cortisol Level Estimation: The patient's serum is required, and a 24-hour urine sample is collected in a plastic container with boric acid. The serum remains stable for 2 days if stored at 2° to 8°C.

For Catecholamines (Epinephrine and Norepinephrine): Plasma in EDTA or heparin is needed. The sample is transported with an ice-pack, centrifuged immediately at 4°C, and plasma is separated and frozen until testing. A 24-hour urine sample may also be collected in a plastic container containing 6 ml of 20% HCl and refrigerated during collection.

Estrogen Estimation: Serum is collected in a plain test tube, centrifuged immediately, and refrigerated until testing. A 24-hour urine sample is also collected in a plastic container with boric acid.

Aldosterone Testing: Plasma (EDTA, citrate, or heparin) or patient's blood serum may be used. The patient must be upright for 2 hours before sample collection. A 24-hour urine sample is also collected in a plastic container with boric acid.

Precautions Before Performing Adrenal Gland Tests

• Fasting blood samples are required.
• Avoid herbal medicines and any medications that may interfere with the test.
• Avoid nuclear scans before this test.
• Avoid exercise or physical activity.
• Reduce stress before the test.
• Aldosterone levels are higher in the morning than in the evening.
• Cortisol levels peak at 8 AM and drop by more than 50% at 8 PM.

Normal Values

• Plasma Epinephrine: <50 pg/mL
• Norepinephrine: 110 to 410 pg/mL
• Cortisol (serum): 5 to 20 µg/dL
• Urine Cortisol (free): 20 to 90 µg/day
• Aldosterone (recumbent): 50 to 150 ng/L
• Aldosterone (upright): 150 to 300 ng/L

Estrogen

• Male: 20 to 80 pg/mL
• Female (Luteal phase): 160 to 400 pg/mL
• Female (Follicular phase): 60 to 200 pg/mL
• Postmenopausal: <130 pg/mL