Addison's disease/ Adrenal insufficiency Flashcards
Adrenal insufficiency
Where the adrenal glands do not produce enough steroid hormones
Cortisol and aldosterone
Addison’s disease
Adrenal glands damaged resulting in reduction in secretion of cortisol and aldosterone
Also called primary adrenal insuffieicny
Most common cause of Addison’s disease
Autoimmune
Secondary adrenal insufficiency
Results of inadequate ACTH stimulating the adrenal glands resulting in low cortisol release
Causes of secondary adrenal insufficiency
Surgery to remove a pituitary tumour
Infection
Loss of blood flow
Radiotherapy
Sheehan’s syndrome (pituitary gland necrosis)
Tertiary adrenal insufficiency
Result of inadequate CRH release by the hypothalamus
Causes of tertiary adrenal insufficiency
Long term oral steroids
- when exogenous steroids are suddenly withdrawn, the hypothalamus doesn’t wake up fast enough and endogenous steroids are not adequately produce
Symptoms of adrenal insufficiency
Fatigue
Nausea
Cramps
Abdominal pain
Reduced libido
Signs of adrenal insufficiency
Bronze hyperpigmentation to skin (ACTH stimulates melanocytes to produce melanin)
Hypotension
Blood test findings
Hyponatraemia
Hyperkalaemia
Test of choice for adrenal insufficiency
Short synacthen test (ACTH stimulation test)
ACTH test
Plasma cortisol measured before and 30 and 60 minutes after giving synacthen IM
Primary adrenal insufficiency short synacthen test findings
Adrenals cant produce cortisol so failure of cortisol to rise indicates Addison’s
Treatment of adrenal insuffiency
Hydrocortisone as glucocorticoid to replace cortisol (majority of dose given in the first half of the day)
Fludrocortisone is mineralocorticoid to replace aldosterone if also insufficient
Addisonian crisis symptoms
Reduced consciousness
Hypotension
Hypoglycaemia
Hyponatraemia
Hyperkalaemia