Addison’s Disease/Primary adrenocortical insufficiency/Adrenal hypofunction:
Rare – maybe 8/1000000. Originates in adrenal gland (secondary type originates outside). Characterised by decreases secretion of mineralocorticoids, glucocorticoids and androgens.
70-80% due to idiopathic hypertrophy of adrenal cortex – probably autoimmune (symptoms occur when 90% of gland destroyed).
Other causes – granuloma (eg TB), tumour, tuberculosis, amyloidosis, inflammatory necrosis, haemorrhage into gland.
Inadequate aldosterone disturbances of sodium, potassium and water metabolism.
Inadequate cortisol abnormal metabolism of fat, protein and carbohydrate metabolism.
May be insidious or acute.
Weakness, weight loss, fatigue, nausea, vomiting, hypoglycaemia, hypokalaemia, orthostatic hypotension, low metabolic rate, increased insulin sensitivity, hypoglycaemia, increased pigmentation (appears like diffuse tanning/bronzing, due to MSH from pituitary), joint and muscle pains, confusion, craving salty foods
Adrenal crisis – profound asthenia, abdominal pain, weakness, dehydration, peripheral vascular collapse, renal shutdown. Often precipitated by acute infection, trauma, surgery in those with adrenal hypofunction – stores of glucocorticoids are exhausted..
In children – behavioural problems; in newborn gravely ill (tachycardia, hypotension, tachypnoea, ever, cyanosis, cold and clammy skin)
Glucocorticoid replacement therapy (lifelong).
Restoration of fluid and electrolyte imbalance (high sodium, low potassium, fluids)
If adrenal crisis fluid replacement, glucose, IV hydrocortisone
In children, weight gain and poor growth can be consequence of long term corticosteroid replacement.