Adrenal insufficiency Flashcards
What is Addison’s disease? (Primary Adrenal insufficiency)
Destruction of adrenal cortex → glucocorticoid and mineralocorticoid deficiency
What are some of the causes of Addison’s disease?
Autoimmune destruction TB Metastases eg lung, breast, kidney Congenital hypoplasia Haemorrhage
What are some of the symptoms of Addison’s disease?
Wt loss, anorexia N+V Abdominal pain Diarrhoea/Constipation Lethargy Depression Hyperpigmentation - palmer creases, buccal mucosa Postural hypotension - dizziness Hypoglycaemia Vitiligo Addisonian crisis
Why do you get hyperpigmentation in Addison’s disease?
Excess POMC to create excess ACTH + A MSH (Stimulates melanocyes) to stimulate the adrenals as they are insufficient
ACTH + A MSH have a common precursor so cross reactivity between receptors
What investigations can be done in a patient with suspected Addison’s disease?
Bloods - ↓Na/↑K, ↓glucose, ↓Ca, Anaemia
Short synACTHen test - will exclude Addison’s if ↑ cortisol
CXR + AXR
Plasma renin and aldosterone (would have ↑ renin ↓ aldosterone)
What is the management of Addison’s disease?
Replace - Hydrocortisone
Advise - Don’t stop steroids suddenly, ↑ dose when ill, wear a medic alert bracelet
Follow up - Watch for other autoimmune diseases
Define Secondary Adrenal insufficiency
Insufficiency due to Hypothalamic or Pituitary failure
What are the causes of Secondary Adrenal insufficiency?
Chronic steroid use → suppression of HPA axis
Sheehan’s syndrome
Pituitary microadenoma
What are the features of Secondary Adrenal insufficiency?
Normal mineralocorticoid production
↓ ACTH - so no hyperpigmentation
What is the presentation of an Addisonian crisis?
Usually a known steroid user or patient with Addison’s
Hypoglycaemia
Shock - ↑HR, postural drop, oliguria, confusion
What can precipitate an Addisonian crisis?
Infection/illness
Trauma
Surgery
Stopping long term steroids
What is the management of an Addisonian crisis?
Bloods: cortisol, ACTH, U+E, cultures BM 100mg Hydrocortisone NaCl solution IV Septic screen - Blood cultures, CXR, Urinalysis Treat any underlying cause
