Addison's Flashcards
What is Addison’s disease? Causes?
What are causes of secondary adrenal insufficiency?
Primary adrenocortical insufficency
Destruction of the adrenal cortex leads to glucocorticoid (cortisol) and mineralocorticoid (aldosterone) deficiency
Causes: Autoimmune disease, TB, adrenal metastases (lung. breast, renal)
Secondary adrenal insufficiency
Long term steroid therapy leading to suppression of the pituitary-adrenal axis.
Only becomes apparent on withdraw of steroids.
May be due to disease of adrenal cortex such as autoimmune destruction or disorders of pituitary (ACTH or hypothalamus (CRH)
What are symptoms of Addison’s disease?
Tiredness
Weight loss, anorexia, vague abdominal pain, dizzy, faints, vomiting, diarrhoea/contipation.
Pigmented palmar creases and buccal mucosa - due to increased ACTH - cross reacts with MSH receptors resulting in increased pigmentation) postural hypotension due to fluid depletion, vitiligo
What are actions of cortisol?
Actions of aldosterone?
Increase proteolysis, lipolysis and gluconeogensis
Amino acid uptake
Hepatic glyconeogensis and glycogenolysis
Lipolysis in adipose tissue
Peripheral uptake of glucose
Stimulates Na reabsorption in kidney in exchange of potassium or hydrogen
Promotes water retention
What investigations for Addison’s?
Short ACTH stimulation test (Synacthen test):
Addison’s is excluded if 30 min cortisol >550mmol/L after Synacthen IM.
*in pregnancy/contraceptive pill there is increased cortisol-binding globulin so cortisol levels may be falsely reassuring.
U&E - Hyponatraemia and hyperkalaemia due to reduced aldosterone.
BM - hypoglycaemia duet o reduced cortisol
In Addison’s 9AM ACTH is high. inseondary it is low.
Plasma renin:aldosterone ratio to assess mineralocorticoid status
AXR/CXR to assess any past TB - upper zone fibrosis
21-hydrozylase adrenal autoantibodies
What is treatment for Addison’s disease? How to administer?
Replace steroids - hydrocortisone daily 2-3 doses per day - natural cycle fo corticosteroid release. - even level of glucocorticoid throughout the day.
Avoid giving late was may cause insomnia
Mineralocorticoids to correct postural hypotension, low Na and high K: fludrocortisone PO daily
Adjust both on clinical response
What advice for steroid use?
What bracelet declaring steroid use
Add hydrocortisone to daily intake before strenuous activity/exercise
Double steroids in febrile illness, injury or stress
Syringes and in-date IM hydrocortisone and show how to inject if vomiting prevents oral intake.
How to recognise adrenal crisis and how to give IM hydrocortisone in emergency
Seek medical help
Do not abruptly stop steroids
warn that all prescribing doctors/dnetists/srugens must know of steroid use - give steroid card.
Take extra medication and emergency hydrocroticosn injection when travelling
What should you monitor for in addison’s?
Autoimmune disease - pernicious anaemia
Adrenal crisis
Over-rplacement - hypertension, thin skin, striae, easy bruising, hyperglycaemia, electrolyte abnormalities
Under-replacement - ongoing Addison’s disease symptoms
