Adrenal Insufficiency

Question 1

What is adrenal insufficiency?

Answer 1

Where the adrenal glands do not produce enough steroid hormones, esp Cortisol and Aldosterone

Question 2

What are the 3 types of adrenal insufficiency?

Answer 2

Primary adrenal insufficiency - Addison’s disease - where there is autoimmune destruction of adrenal gland causing low cortisol and aldosterone (commonest)

Secondary adrenal insufficiency - due to inadquate ACTH

Tertiary adrenal insufficiency - inadequate CRH release from hypothalamus

Question 3

What are causes of secondary adrenal insufficiency ?

Answer 3

loss or damage to pituitary gland

• pituitary tumour
• infection
• loss of blood flow (as in Sheehan’s syndrome where massive blood loss during childbirth leads to pituitary gland necrosis)
• radiotherapy

Question 4

What causes tertiary adrenal insufficiency?

Answer 4

exogenous long term steroid therapy (>3 weeks)
if suddenly withdrawn, hypothalamus does not wake fast enough for endogenous steroids to be produced

need to taper of steroids

Question 5

What are other causes of primary adrenal insufficiency?

Answer 5

TB
HIV
Antiphospholipid syndrome
Metsastasis

Question 6

What are the symptoms of Addison’s disease?

Answer 6

lethargy
weakness
nausea and vomiting
collapse and shock in severe cases

Question 7

What are the signs of Addison’s disease

Answer 7

Bronze hyperpigmentation of palmar creases (ACTH stiumulates melanocytes to produce melanin) - only in primary adrenal insufficiency (Addison’s)

Hypotension

Question 8

What is the key metabolic clue? What may also be seen?

Answer 8

Hyponatraemia

may also see
Hyperkalaemia

Hypoglycaemia

Question 9

What test is used to diagnose adrenal insufficiency (Addison’s disease) ?

Answer 9

ACTH stimulation test (short synacthen)

• synthetic ACTH given ideally in the am
• measure cortisol levels baseline, 30 mins and 60 mins
• if less than double baseline - primary adrenal insufficiency can be diagnosed

Question 10

What investigations would you do for Adrenal Insufficiency?

Answer 10

1. Na+ and K+
2. Short synathen test
3. ACTH - primary ACTH is high, secondary ACTH is low
4. early morning cortisol (can be falsely normal)
5. Adrenal autoantibodies present in 80% - 21 hydroxylase antibodies
6. CT/MRI adrenals (tumour or haemorrhage suspected)
7. MRI pituitary

Question 11

which autoantibody is associated with 80% of autoimmune cases?

Answer 11

21-hydroxylase adrenal antibody

Question 12

How is Adrenal insufficiency managed?

Answer 12

Hydrocortisone to replace cortisol
Fludrocortisone to replace aldosterone

consider steroid card and emergency ID tag
advise patients on importance of not missing doses
double dose in acute illness

Question 13

How do patients present in Addisonian Crisis

Answer 13

reduced of consciousness
hypoglycaemia, hyponatraemia, hyperkalaemia
hypotension
very unwell

Question 14

What are causes of Addisonian Crisis?

Answer 14

Infection (sepsis)

withdrawal of steroids

trauma/surgery

Other acute illness

Question 15

How do you manage Addisonian crisis?

Answer 15

Intensive monitoring if unwell
IV/IM hydrocortisone 100mg stat then 100mg every 6 hours until stable

Correct fluid loss and hypoglycaemia
1 litre normal saline over 30-60mins or with dextrose if hypoglycaemic
oral can begin after 24hrs

Careful monitoring of electrolytes and fluid balance