3.3 Disorders of Adrenal Hormone Excess and Deficiency

Question 1

What is a paraganglioma? What type of cells will it affect, and therefore, what hormones will it produce in excess?

Answer 1

• Tumour of chromaffin cells outside the adrenal medulla
• Leads to hypersecretion of adrenaline and noradrenaline

Question 2

List some causes for hypersecretion/high levels of adrenal cortex hormones

Answer 2

• Medications (corticosteroids)
• ACTH hypersecretion (pituitary)
• Ectopic ACTH secretion (?lung tumour)
• Adenoma/carcinoma of adrenal cortex

Question 3

List some causes for hypersecretion of adrenal medulla hormones

Answer 3

• Phaeochromocytoma
• Neuroblastoma
• Paraganglioma

Question 4

List some symptoms of adrenal medulla hormone excess

Answer 4

• Hypertension
• Headache
• Sweating
• Tachycardia

Question 5

What are some causes of adrenal insufficiency?

Answer 5

• Autoimmune adrenal failure (most common cause of Addison’s/1°)
• Fungal infection/tuberculosis
• Cancer destroying adrenals
• Bilateral infarction/haemorrhage
• Insufficient replacement dosage of corticosteroids (missed stress dose etc.)
• Medication withdrawal

Question 6

Adrenal insufficiency (not crisis) symptoms

Answer 6

• Anorexia
• Fatigue
• Weight loss
• Postural dizzines
• Hyperpigmentation
• Hyponatremia, hypokalaemia

Question 7

How do we test for every kind of hormone produced by the adrenal glands?

Answer 7

• Catecholamines (blood, urine)
• Aldosterone (saline suppression)
• Cortisol (salivary/free urinary, dex suppression)
• Androgens (blood test)

Question 8

How does a clonidine suppression test test for the presence of catecholamine-secreting tumours?

Answer 8

• Clonidine is a centrally acting beta 2 agonist
• It suppresses noradrenaline release
• However, tumour cells are unaffected
• Therefore, high NA + clonidine indicates tumour

Question 9

How does a dexamethasone suppression test help us identify cushing’s syndrome?

Answer 9

• Dex suppresses ACTH levels normally
• This leads to decreased cortisol
• Therefore, if cortisol is still high, there’s some production of cortisol outside of the normal feedback loop (?tumour, ?ectopic ACTH etc.)

Question 10

Describe saline suppression tests for primary aldosteronism

Answer 10

• Administer saline
• Normally, this would suppress the RAAS system, decreasing aldosterone
• Therefore, if aldosterone levels remain high, there is some secretion outside of the normal feedback loop (?tumour)

Question 11

We want to assess the structure of the adrenal glands to check for possible tumours? What imaging modality do we most commonly use?

Answer 11

CT

Question 12

Adrenal insufficiency crisis symptoms

Answer 12

• Hypotension
• Shock
• Syncope
• Abdominal pain
• Delirium
• Hyponatremia, hypokalaemia

Question 13

Broadly, describe treatment of adrenal insufficiency

Answer 13

• Replacement therapy
• Stress dosage
• In 1°, give fludrocortisone to replace mineralocorticoids
• In 2° not needed, but still give glucocorticoid such as pred or dex

Question 14

What hormones will we need to replace with drugs in 21-hydroxylase deficiency?

Answer 14

• Glucocorticoids
• Mineralocorticoids

(Androgens are fine; remember enzymatic pathway)

Question 15

Describe medical and surgical treatment for primary aldosteronism

Answer 15

Medical: diuretics (e.g. epleronone) and mineralocorticoid receptor antagonists (e.g. spironolactone)

Surgical: partial or total removal of one or more adrenals (adrenalectomy)

Question 16

Primary cushings treatment; reversible and irreversible

Answer 16

Reversible:
- Ketoconazole (unknown mech)

Irreversible:
- Adrenalectomy
- Mitotane (anti-tumour; kills healthy/unhealthy adrenal cells)

Question 17

Cushing’s Disease treatment; reversible and irreversible

Answer 17

Irreversible:
- Removal of pituitary tissue
- Radiotherapy

Reversible:
- Somatostatin analogues

Question 18

Cushing’s disease vs syndrome

Answer 18

Disease: hypersecretion of ACTH
Syndrome: symptoms that occur in a state of cortisol excess