Endocrine - Adrenal Insufficiency Flashcards
What is Addison’s disease?
Autoimmune damage to the adrenal glands resulting in reduced cortisol and aldosterone secretion
What is secondary adrenal insufficiency?
Inadequate ACTH resulting in lack of production by adrenal glands
Due to damage to pituitary gland
What can cause secondary adrenal insufficiency?
Tumours
Surgery
Radiotherapy
Sheehan’s syndrome
Trauma
What is tertiary adrenal insufficiency?
Inadequate CRH from hypothalamus
What usually causes tertiary adrenal insufficiency?
Long-term oral steroids (3 weeks or more)
Suppression of hypothalamus
Why do you ween patients off of steroids?
Hypothalamus does not respond fast enough and endogenous steroids not produced quickly enough
How do patients with adrenal insufficiency present?
Fatigue
Thirst and craving salt
Muscle weakness and cramps
Abdominal pain
Reduced libido
What are the signs of adrenal insufficiency?
Bronze hyperpigmentation (particularly in creases)
Hypotension (particularly postural hypotension)
What is the key finding in adrenal insufficiency?
Hyponatraemia
What electrolyte changes may there be?
- Hyperkalaemia
- Hypoglycaemia
- Raised creatinine and urea due to dehydration
- Hypercalcaemia
What is the gold standard for diagnosing adrenal insufficiency?
Short Synacthen test
What autoantibodies may be present in autoimmune adrenal insufficiency?
Adrenal cortex antibodies
21-hydroxylase antibodies
What is the short Synacthen test?
ACTH stimulation test
Dose of Synacthen given (synthetic ACTH)
Cortisol checked before and 30 and 60 minutes after the dose
Should double cortisol levels
Failure indicates:
- Primary adrenal insufficiency (Addison’s disease)
- Significant adrenal atrophy after prolonged reduced ACTH
How is adrenal insufficiency treated?
Hydrocortisone to replace cortisol (glucocorticoid)
Fludrocortisone to replace aldosterone (mineralocorticoid)
Patients given steroid card, ID tag and emergency letter
Doses are essential to life
During acute illness what happens to steroid dosage?
Doses are doubled to match normal steroid response to illness
