Diagnosis of Adrenal Disease Flashcards
What is cortisone?
A metabolite of cortisol that must be activated in the liver
What is adrenal crisis?
Deficient salt and water retention due to low aldosterone
What are some causes of ACTH-independent hypercortisolism?
Adrenal adenoma or carcinoma
ACTH-independent nodular hyperplasia
Administration of glucocorticoids
If you remove the adrenals, a deficit of what will cause rapid death?
Aldosterone
What is the mnemonic for the layers of the adrenal cortex and what they produce?
Go Find Rex, Make Good Sex
Glomerulosa - Mineralocorticoids
Fasiculata - Glucocorticoids
Reticularis - Sex steroids
Which infectious disease can destroy the adrenals?
TB
What causes Cushing’s disease?
A pituitary adenoma
What are the main physiological effects of aldosterone?
Increase Na and water retention
K excretion
What is the pathogenesis of CAH?
Deficiency in 21-hydroxylase > Can’t produce cortisol and aldosterone > high ACTH > adrenal hyperplasia and over production of androgen
What is ectopic ACTH syndrome?
Abnormal production of ACTH by a tumour - typically lung tumours
What is hydrocortisone?
Cortisol
What are the symptoms of Addison’s?
Salt wasting - low serum Na, high K, hypotension
Muscle weakness
Pigmentation
Weight loss, decreased appetite
GI symptoms
What is CAH?
Congenital adrenal hyperplasia
Where is pigment seen in Addison’s?
Areas of high friction
- Knees
- Hands
- Gums (pathognomonic) & oral mucosa
Adrenal androgen excess can course what?
Premature pubic hair
Precocious puberty
Hirsutism, acne
Enlargement of penis or clitoris
Behavioural change
Rapid epiphyseal fusion
What is Conn’s syndrome?
Aldosterone excess due to aldosterone producing adrenocortical tumour
What tests can you do as alternatives to testing a hormone level at a single time point?
Hormone and trophic hormone
Stimulation
Suppression
24hr urine - patients don’t like
What is the pathogenesis of Addison’s?
Destruction of the adrenal gland (usually autoimmune in Aus) resulting in deficiency in cortisol
What does cortisol deficiency cause?
GI symptoms
Low BP
Darkening of skin
Muscle weakness
Increase susceptibility to infection
DEATH
How does Pheochromocytoma present?
Episodic bursts of secretion of catacholamines = palpitation, increase BP, pallor, feeling of impending doom
Why do you do biochemical tests before radiology?
Because you bound to find something with radiology - it probably won’t be helpful useless you’re looking for something specific
What investigations do you order for suspected Cushing’s
24hr urine free cortisol
Diurnal variation, 800 and midnight - path labs aren’t open late
Dexamethasone supp’n test
Cranial MRI/adrenal CT
Why do you get weakness with excess aldosterone?
Hypokalaemia
What are the stimulators of aldosterone production?
Increase K in extracellular fluid
Angiotensin II
How does too much cortisol cause hypertension?
Salt retention - due to aldosterone mirroring effects of cortisol
