Adrenal gland: physiology and disease Flashcards
What is the most common cause of adrenal insufficiency?
Addison’s disease
-autoimmune destruction of the adrenal glands
What are the causes of secondary adrenal insufficiency?
-Lack of ACTH stimulation
Pituitary/hypothalamic disorders
What are the clinical features of Addison’s disease?
FAD AS
Fatigue
Anorexia
Dizziness, low BP
Abdo: pain, vomiting, diarrhoea
Skin pigmentation
How is adrenal insufficiency diagnosed?
- Synacthen test
- IV ACTH and measure cortisol - ACTH levels (elevated)
- Increased renin
- Low aldosterone
- Adrenal autoantibodies
How is primary adrenal insufficiency managed (what needs to be replaced)?
- Hydrocortisone - cortisol replacement
2. Fludocrtisone - aldosterone replacement
What is the management of secondary adrenal insufficiency (lack of Corticotropin releasing hormone or Adrenocorticotropic hormone)?
- Surgery/radiotherapy for pituitary / hypothalamic tumours
2. reduce exogenous steroids
What are the clinical features of Cushing’s syndrome?
- easy bruising
- facial plethora
- striae
- proximal myopathy
What are the ACTH-dependent causes of Cushing’s?
- Pituitary adenoma
2. Ectopic ACTH production
What are the ACTH-independent causes of Cushing’s?
- Adrenal adenoma
- Exogenous steroids
- Adrenal carcinoma
What are the cardiovascular actions of aldosterone?
Increases:
- Blood pressure
- CV damage - atheroma,
- Left ventricular hypertrophy
What are the common causes of Primary Aldosteronism?
- Adrenal hyperplasia (60%)
2. Conn’s sydnrome - adrenal adenoma (30%)
Primary aldosteronism is the most common cause of secondary _______
secondary hypertension
How is primary aldoteronism diagnosed?
- Check for ALdosterone excess
- plasma aldsoterone/renin ratio - Adrenal CT to confirm adenoma
What is the management of of Primary Aldosteronism?
- Adrenal adenoma: Laprascopic adrenalectomy
2. Spironolactone - mineralocorticoid antagonist
What is the most common Congenital Adrenal Hyperplasia?
21-alpha hydroxylase deficency
