Addisons Disease Flashcards
what is addisons disease also known as
primary adrenal insufficiency
give the main glucocorticoid
cortisol
give the main mineralocorticoid
aldosterone
what is addisons
autoimmune destruction of the adrenal gland causing reduced aldosterone and cortisol production
what hormone stimulates hormone production in the adrenal and what produces it
ACTH
pituitary
what are some other causes of primary adrenal insufficiency
TB adrenal metastases adrenal haemorrhage (seen in SLE and antiphospholipid) lymphoma opportunistic infections eg HIV congenital
what hormone profile would you see in primary adrenal insufficiency (addisons)
high ACTH
low cortisol and aldosterone
what are some of the clinical features of hypoadrenalism
- lethargy, weakness, nausea and vomiting, weight loss
- hyperpigmentation, vitiligo
- hypoglycaemia
what electrolyte abnormalities might you see in hypoadrenalism
low sodium
high potassium
what abnormalities might you see on blood results in hypoadrenalism
uraemia
eosinophilia
anaemia
increased calcium
what is the primary investigation for hypoadrenalism
short acting ACTH stimulation test (synacthen test)
how does a synacthen test work
Plasma cortisol is measured before and 30 minutes after giving Synacthen 250ug IM.
This SHOULD cause plasma cortisol to rise. In addisons disease it will NOT.
what time of day should you monitor cortisol
morning (peaks at this time)
what antibodies might be positive in autoimmune adrenal insufficiency
21-hydroxylase adrenal autoantibodies
what investigations would you want to do in a patient with suspected hypoadrenalism
- FBC
- U&E (looking for uraemia, low sodium, high potassium)
- ESR/CRP
- short synacthen test
- morning serum cortisol
- plasma ACTH
- plasma renin and aldosterone
- 21-hydroxylase antibodies
- adrenal CT/MRI
what can cause secondary adrenal insufficiency
most common = IATROGENIC from long term steroid therapy
also any pituitary causes eg. irridation, infiltration, tumours
what do enlarged adrenals on CT/MRI suggest
infectious, haemorrhagic or metastatic disease
what might cause an addisonian crisis
- abrupt withdrawal of steroids
- sepsis or surgery
- adrenal haemorrhage
how should you manage an addisonian crisis
hydrocortisone 100mg IM or IV
fluid resus
continue hydrocortisone 6hrly until patient is stable
how do you manage addisons disease
replace both mineralocorticoids and glucocorticoids
normally involves a regimen of both
HYDROCORTISONE and FLUDROCORTISONE
what should you make sure to do during intercurrent illness
make sure to increase steroid doses (double)
what is the opposite of addisons disease
cushings disease
