Adrenal disease

Question 1

What is the main cause of primary adrenocortical insufficiency?

Answer 1

80% are due to autoimmunity in UK

TB commonest cause worldwide

Question 2

What is the commonest cause of secondary adrenocortical insufficiency?

Answer 2

Iatrogenic (exogenous steroids) Suppressing HPA axis

Question 3

What does the term addisons disease refer to?

Answer 3

Refers to the primary adrenocortical insufficiency

Question 4

What are some symptoms of addisons and secondary adrenocortical insuffiency?

Answer 4

Tiredness is main symptom often
anorexia, weight loss, weakness, postual hypotension, nausea and vomiting.
In addisons there is hyperpigmentation from excess ACTH, hyperkalaemia and hyponatraemia (mineralocorticoid deficiency)

Question 5

What abnormalities will be found on blood tests for adrenal insufficiency?

Answer 5

Hyponatraemia, hyperkalaemia and ureamia

Question 6

What tests can be done to diagnose addisons and when should they be used?

Answer 6

Short synthacten test is a stimulation test (mimics ACTH) that should cause cortisol to rise in normal individuals
Long synthacten test is used to differentiate between primary and secondary adrenal failure, in secondary it should cause a rise in cortisol after a few hours but in primary it will not cause a rise

Question 7

How will renin levels change in primary and secondary adrenal insufficiency?

Answer 7

In primary adrenal insufficiency renin will be raised as there is lack of mineralcorticoid stimulating negative feedback

Question 8

What methods can be used to establish the cause of addisons disease once it has been diagnosed?

Answer 8

Can do adrenal autoantibodies to look for an autoimmune cause
Can do imaging of the adrenals e.g. CT if this shows enlargement/calcification then it suggests infiltration/TB, if they are small and atrophied this suggests autoimmune adrenalitis

Question 9

What are some signs of acute adrenal insufficiency?

Answer 9

Shock
Hypotension
Abdominal pain
Unexplained fever
Background of adrenal insufficiency
It is usually precipitated by stress such as infection or trauma

Question 10

How is acute adrenal insufficiency diagnosed?

Answer 10

investigated same as chronic but in the acute setting can be diagnosed by low cortisol alone

Question 11

What is the management of acute adrenal insufficiency?

Answer 11

Large volumes of 0.9% saline should be given over first 24 hours to compensate for hypovalemia
Immediate IV bolus of 100mg hydrocortisone should be given followed by 100mg hydrocortisone IM every 6 hours until patient can take orally
Glucose supplementation is sometimes required

Question 12

What is something to be careful of when volume replacing an acute adrenal insufficiency patient?

Answer 12

If they are extremely hyponatraemic (<120mmol/L) then need to correct the volume slowly in the first 24 hours to avoid pontine myelinolysis

Question 13

What is the long term maintenance therapy in Addison’s?

Answer 13

10mg hydrocortisone on waking, 5mg at lunch, 5mg in the evening
100 ug OD Fludrocortisone is used as mineralocorticoid replacement

Question 14

How do corticosteroids travel in the bloodstream?

Answer 14

Bound to corticosteroid binding globulin

Question 15

What are some of the effects that glucocorticoids have on the body?

Answer 15

They effect gluconeogenesis, amino acid generation and lipolysis
Partial agonistic effect at mineralcorticoid receptors affecting salt and water balance

Question 16

What is the normal rhythm of cortisol release?

Answer 16

Normally peak in the morning then taper down throughout the day

Question 17

What are some of the classical clinical signs of cushing’s syndrome?

Answer 17

Increase in fat tissue, moon face, central obesity
Breakdown of collagen causes thin skin and easy bruising, myopathy and osteoporosis
Androgen excess causes acne, plethora and hirtusism

Question 18

What tests should be done for cushings investigation?

Answer 18

24 hr urinary free cortisol (elevated in cushings)

Dexamethasone suppression test

Question 19

What does the overnight dexamethasone suppression test show in cushings?

Answer 19

Shows a non depressed cortisol in the morning. In normal individuals the exogenous steroid will cause ACTH suppression resulting in a low cortisol level in the morning (<50nm/L)

Question 20

How can you differentiate ACTH dependent and independent causes?

Answer 20

ACTH dependent causes will have raised ACTH whereas independent it will be very low

Question 21

What blood test is useful for ectopic ACTH secreting tumours?

Answer 21

Potassium as they will have hypokalaemia

Question 22

How can you differentiate Cushings disease (ACTH secreting pituitary tumour) from ectopics?

Answer 22

High dose dexamethasone suppression test will cause some suppression in Cushing’s but not in ectopics
100 ug CRH will cause exaggerated release of cortisol in cushings but not ectopics

Question 23

What is the treatment for cushing’s disease?

Answer 23

Transphenoidal surgery to remove pituitary adenoma
Should be given hydrocortisone afterwards as they will be deficient for a while
Can use pituitary radiotherapy if this is unsuccessful

Question 24

What is done if the pituitary adenoma is resistant to surgery?

Answer 24

Bilateral adrenalectomy can be used

Question 25

What is the difference between cushings disease and cushings syndrome?

Answer 25

Cushings disease is caused by a pituitary hypersecretion of ACTH. Cushings syndrome is the result of excess cortisol in the body regardless of the cause

Question 26

What are the common causes of Ectopic ACTH production?

Answer 26

Small cell lung cancers and carcinoid tumours (neural crest cell)

Question 27

What are the ACTH independent causes of increased cortisol?

Answer 27

Iatrogenic - most common (e.g. steroids)
Adrenal adenoma
Adrenal nodular hyperplasia

Question 28

What is conn syndrome?

Answer 28

This is primary hyperaldosteronism, often asymptomatic and usually due to solitary aldosterone producing adenoma

Question 29

What is the treatment for conns syndrome?

Answer 29

It is treated with laproscopic adrenalectomy

Spironolactone is required for 4 weeks post op to control K+ and BP (prevents hypokalaemia)