Adrenal Insufficiency Flashcards
(20 cards)
Addison’s disease is also known as..?
What are the features?
Primary adrenal insufficiency
Lethargy, weakness, anorexia, nausea, vomiting, weight loss, salt craving, hyperpigmentation, vitiligo, postural hypotension
What is the most common cause of Addison’s disease in the developed world? In the developing world?
Developed world: Auto-immune
Developing world: Tuberculosis
What would be found on U&Es and on an ABG in patients with Addison’s disease?
Hyponatraemia
Hyperkalaemia
Metabolic acidosis
What do different regions of the Adrenal Cortex produce?
Zona Glomerulosa: Aldosterone
Zona Fasciculata: Cortisol + other Glucocorticoids
Zona Recticularis: Androgens
What findings would be present in patients where the Zona Glomerula were affected in Addison’s disease?
Loss of aldosterone, hence hyponatraemia, hyperkalaemia, metabolic acidosis. Hypovolaemia (postural hypotension) could also occur
What findings would be present in patients where the Zona Fasciculata were affected in Addison’s disease?
Loss of cortisol -> hypoglycaemia. Upregulation of POMC and CRH -> producing more ACTH and MSH leading to hyperpigmentation
What findings would be present in patients where the Zona Recticularis were affected in Addison’s disease?
Men: little effect
Women: lose pubic hair and sex drive
What things may trigger an Addisonian crises?
Infection, surgery, stress, abruptly stopped steroids
What are symptoms of an Addisonian crisis?
Vomiting and diarrhoea
Low blood pressure
Sudden pain in back, knees, legs
How do you treat an Addisonian crises?
High dose corticosteroids
IV saline
On X-ray, what finding may be present in a patient with Addison’s?
Calcification of the adrenal glands
- What are some investigations for Addison’s disease?
- U&Es - hyponatraemia, hyperkalemia
- ABG - Metabolic acidosis
- Short Synacthen test = Cortisol fails to increase after 30mins
- Early morning cortisol (often falsely normal)
- Plasma Aldosterone levels = Low
- Endogenous ACTH measurements = High
- Anti-adrenal antibodies
MRI pituiatry
What is the first-line diagnostic test for Addison’s disease? How is it performed, what results could you expect?
Short Synacthen test
Administer IM Synacthen, then measure Cortisol 30 mins after. If Cortisol fails to increase -> Addison’s
What findings for Cortisol and ACTH would you expect in Primary adrenal insufficiency?
Cortisol - Low
ACTH - High
What findings for Cortisol and ACTH would you expect in Secondary adrenal insufficiency?
Cortisol - Low
ACTH - Normal / Low
In Secondary adrenal insufficiency, why do you not see hyperpigmentation?
Secondary adrenal insufficiency is characterised by low / normal levels of ACTH. A lack of ACTH production means that there is also a lack of POMC, and hence a lack of MSH which causes hyperpigmentation
In primary adrenal insufficiency the low Cortisol sends a feedback mechanism to upregulate ACTH which does so by increasing POMC (its pre-cursor) to synthesis both ACTH and MSH
- What is the treatment for Addison’s disease?
- During acute illness, what changes?
- What does hydrocortisone and Fludrocortisone replace?
- Hydrocortisone + Fludrocortisone
- Double hydrocortisone, keep Fludrocortisone the same
- Hydrocortisone replaces cortisol, Fludrocortisone replaces Aldosterone
If an Addison’s disease patient is systemically unwell, how would you change their treatment regime of Hydrocortisone and Fludrocortisone?
Double hydrocortisone only
Which anti-adrenal antibodies may cause adrenal insufficiency
Adrenal cortex antibodies
21-hydroxylase antibodies
What abnormality would corticosteroids create on an FBC
Neutrophilia
