Endocrinology Session 4 CLINICAL Flashcards
How to remember what the adrenal hormones act on?
Salt, sugar, sex
How does cortisol deficiency present?
Weakness
Tiredness
Weight loss
Hypoglycaemia
How does mineralocorticoid deficiency present?
Dizziness
Hyponatraemia
Hyperkalaemia
How does androgen deficiency present?
Low libido
Loss of body hair in women (as adrenal gland only source of testosterone)
How does cortisol excess present?
Weight gain
Cushingoid features
How does mineralocorticoid excess present?
Hypertension
Hypokalaemia
How does androgen excess present?
Increased male characteristics in women
How does excess ACTH present?
Skin pigmentation due to melanocyte stimulation
How does adrenal medulla disease present?
- Excess catecholamine secretion (due to a pheochromocytoma)
- Acute episodes
- Sweating
- Anxiety
- Palpitations
- High/low BP
- Collapse
- SUDDEN DEATH
What biochemical tests would you do if adrenal hormone deficiency is suspected and what would they show?
- Electrolytes: low Na, high K (aldosterone), low Na but normal K (ACTH deficiency)
- 0900 basal cortisol: low
- Stimulation test: synthetic ACTH
What biochemical tests would you do if adrenal hormone excess was suspected and what would they show?*
- Electrolytes: High BP, low K
- Midnight cortisol: high (should be low)
- 24h urine cortisol: high
- Suppresion test: cannot suppress
- Androgens: high
What biochemical tests would you do to assess the adrenal medulla?
- 24h urine catecholamines (NAd, Ad, dopamine)
- 24h urine metanephrines- breakdown products of catecholamines (metadrenaline, normetadrenaline)
- plasma metanephrines (more sensitive)
Which foods should be avoided before collection of urine?
Eg. coffee and coke
How do you radiologically assess adrenal disease?*
- CT scans
- MRI scans
- Functional imaging: MIBG and PET scans
What can cause adrenal insufficiency?
- Primary adrenal failure
- Destruction of adrenal cortex
- Addison’s disease
What can cause secondary adrenal failure?
ACTH deficiency from hypopituitarism
What can cause steroid-induced hypoadrenalism?
ACTH suppression
What are the symptoms of Addison’s disease?*
- Fatigue
- Weakness
- Anorexia
- Weight loss
- Nausea
- Abdominal pain
- Dizziness
- Pigmentation
What are the signs of Addison’s disease?
- Underweight with signs of weight loss
- General malaise
- Other autoimmune disease (eg. vitiligo, thyroid disease)
- Postural hypertension
- Pigmentation
What can cause primary adrenal failure?
- Autoimmune
- Infection (TB, AIDS)
- Haemochromatosis
- Malignancy (lung, breast)
- Genetic
- Vascular (haemorrhage/infarction)
- Iatrogenic (drugs or adrenalectomy)
What is adrenal crisis?*
A medical emergency caused by extremely low cortisol levels (low ACTH doesn’t act as well on the adrenal gland so doesn’t produce cortisol or aldosterone)
What are the clinical features of an adrenal crisis?*
- Collapse
- Hypotension
- Dehydration
- Pigmentation
- Coma
- ‘Flat’ response to synacthen (poor response of adrenal gland to ACTH)
How do you treat adrenal crisis?
- Rapid rehydration
- Treat underlying cause
- IV hydrocortisone
How do you maintain and stabilise Addison’s disease?
- Lifelong replacement of glucocorticoids and mineralocorticoids (hydrocortisone, prednisolone, fludrocortisone)
How do you prevent crises?
- Double dose of glucocorticoid when ill
- Emergency hydrocortisone if vomiting
- Card and bracelet that steroid medications should not be immediately stopped
When does ACTH deficiency occur?
In any cause of hypopituitarism (secreted from pituitary gland so if not working/smaller - less ACTH)
What symptoms do/do not appear in ACTH deficiency?
- No pigmentation (ACTH low not raised)
- No hyperkalaemia (no mineralocorticoid deficiency)
- Hyponatraemia (cortisol affect on free water excretion as regulates ADH)
What can cause Cushing’s syndrome?
- Ectopic ACTH
- Pituitary and adrenal tumours
What are the clinical signs of Cushing’s syndrome?
- Round pink face
- Round abdomen
- Skinny, weak arms and legs
- Thin skin
- Easy bruising
- Abdominal striae
- Hypertension
- Diabetes
- Osteoporosis
What is adrenal Cushing’s syndrome?
- Adrenal tumour that secretes glucocorticoids
- May secrete cortisol metabolites alongside
- ACTH-independent Cushing’s
How might adrenal Cushing’s present?
- Hirsutism
- Acne
- Greasy skin
- Androgenic alopecia
- Clitoromegaly
- Deep voice
What is Addison’s disease?
A disease caused by low levels of glucocorticoids and mineralocorticoids
How do you treat adrenal Cushing’s syndrome?
- Laparoscopic adrenalectomy
- If large tumour, needs open surgery
Careful of the risk of postop hypoadrenalism due to adrenal suppression)
What is primary hyperaldosteronism?*
Excess production of aldosterone, caused by either aldosterone-secreting adenoma (Conn’s syndrome) or bilateral adrenal hyperplasia
How can primary hyperaldosteronism present?*
- Hypertension at young age
- Hypokalaemia plus hypertension
- High aldosterone = low renin
How do you diagnose primary hyperaldosteronism?*
- Hypertension and hypokalaemia investigate
- High aldosterone and suppressed renin
- Scan showing adenoma or bilateral hyperplasia
- May need functional scan
How do you treat primary hyperaldosteronism?
- Conn’s adenoma: surgery
- Bilateral hyperplasia: aldosterone antagonists (spironolactone)
What is congenital adrenal hyperplasia?
An autosomal recessive disorder causing an adrenal crisis and ambiguous genitalia after birth (INCEST)
What causes CAH?*
A block in the adrenal cortex pathway caused by an enzyme defects that causes low cortisol and aldosterone, but high androgen
Most common is 21-hydroxylase deficiency
How does CAH present?*
- Hypotension
- Hyponatraemia
- Hyperkalaemia
- Hypoglycaemia
- Ambiguous genitalia (clitoromegaly)
How do you treat CAH?
- Treat crisis
- Long term glucocorticoids and mineralocorticoids
- Corrective surgery
What is a phaeochromocytoma?
A tumour of the adrenal medulla
What is a paraganglioma?
An extra-adrenal tumour that has the chromaffin tissue origin
What are the symptoms of phaeochromocytoma and paraganglioma?
- Acute episodes
- Sweating
- Panic attacks
- Palpitations
- High/low BP
- Collapse
If acute:
- Hypertensive crisis
- Encephalopathy
- Hyperglycaemia
- Cardiac arrhythmias
- Sudden death
FINISH SLIDE 47
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