Hypoadrenalism

Question 1

Where are the adrenal glands?

Answer 1

On top of kidneys

Question 2

The adrenal glands have two sections, name them?

Answer 2

Medulla

Cortex

Question 3

What does the medulla secrete and when does it secrete?

Answer 3

Adrenaline
Noradrenaline

In response to sympathetic stimulation

Question 4

What does the cortex secrete?

Answer 4

Corticosteroids:

• mineralcorticoids
• glucocorticoids
• androgens

Question 5

What are the corticosteroids made of?

Answer 5

Cholesterol

Question 6

Give some examples of:

• mineralcorticoids
• glucocorticoids
• androgens?

Answer 6

Mineralcorticoids: aldosterone

Glucocorticoids: cortisol

Androgens: sex hormones, testosterone

Question 7

Name the 3 regions of the cortex of each adrenal glands going from outside - in?

Answer 7

Zona glomerulosa
Zona fasciculata
Zona reticularis

Question 8

Describe/draw axis of cortisol?

Answer 8

Hypothalamus releases CRH (corticotrophic releasing hormone)

This acts on pituitary making it release ACTH (adrenocorticotrophic hormone)

This acts on adrenals making them produce cortisol

Question 9

What does cortisol do?

Answer 9

Helps body overcome stress
Decreased immune function
Maintain BP
Metabolism of fats, proteins
Circadian rhythms

Question 10

Describe how cortisol is involved in control of circadian rhythms?

Answer 10

Light falls on retina

Transmission of impulses from eye to the central clock, in the hypothalamus

This then triggers the release of cortisol which wakes the body up

Question 11

What is the name for primary hypoadrenalism?

Answer 11

Addison’s disease

Question 12

What is Addison’s disease?

Answer 12

Autoimmune destruction of the adrenal cortex

Reduction in ability to produce cortisol, aldosterone and androgens

Question 13

Clinical features of Addison’s disease?

Answer 13

Insidious onset

Lethargy, fatigue
Depression
Anorexia
Weight loss
Weakness

Postural hypotension

Hyperpigmentation

Loss of body hair in women
Vitiligo: loss of pigment of skin

Question 14

Where does hyperpigmentation occur in Addison’s disease? And why?

Answer 14

Seen in buccal mucosa (mouth)
Pressure points
Skin creases
Recent scars

Caused by excess ACTH which stimulates melanocytes to make the skin darker

Question 15

Why are there higher levels of ACTH in Addison’s disease patients?

Answer 15

Because the pituitary gland senses no cortisol/aldosterone/androgens coming from adrenals

It tries to stimulate the adrenals to make more

Question 16

What causes Addison’s disease to develop?

Answer 16

Organ specific antibodies

There are links with other autoimmune diseases

Adrenal gland TB
Surgical removal

Question 17

Investigation of Addison’s disease?

Answer 17

Hyponatraemia
Hyperkalaemia
Hypoglycaemia

Random cortisol levels low

ACTH stimulation test (SynACTHen test)

Question 18

What is the ACTH stimulation test?

Answer 18

Synacthen test

Patient is given synthetic ACTH to stimulate cortisol production

Cortisol levels should rise sharply, but they don’t in Addison’s disease

Question 19

Why does Addison’s disease cause hyponatraemia and hyperkalaemia?

Answer 19

Low aldosterone levels means less sodium is retained in the tubules and less potassium is secreted

Question 20

Treatment of Addison’s disease?

Answer 20

Replacement!

Hydrocortisone: replacement cortisol

Fludrocortisone: replacement aldosterone

Question 21

What happens if you over-replace cortisol in Addison’s disease?

Answer 21

You get endogenous Cushing’s syndrome

Question 22

In healthy people, when do cortisol levels rise?

Answer 22

3rd trimester of pregnancy

During stressful time like trauma, surgery, illness

Question 23

What is an adrenal crisis?

Answer 23

Also known as Addisonian crisis

When an event such as trauma or illness, causes severe hypotension and dehydration

Question 24

Clinical features of an adrenal crisis?

Answer 24

Vomiting
Abdominal pain
Profound weakness
Hypoglycaemia
Hypovolaemic shock

Question 25

Management of adrenal crisis?

Answer 25

Give 100mg bolus of hydrocortisone

Followed by 6 hourly IM

Question 26

You are presented with a patient who you suspect may be in adrenal crisis, but you aren’t certain. What should you do?

Answer 26

Give hydrocortisone anyway to be on the safe side, if they don’t have adrenal crisis, the steroids won’t do any harm

Question 27

Difference between primary and secondary adrenal insufficiency?

Answer 27

Primary: problem with adrenals, they aren’t producing cortisol

Secondary: under-stimulation of adrenals by the pituitary or hypothalamus

Question 28

Clinical features of secondary adrenal insufficiency?

Answer 28

Same as primary but minus the skin pigmentation

Insidious onset
Lethargy, fatigue
Depression
Anorexia, weight loss

Postural hypertension

Loss of body hair in women
Vitiligo: loss of pigment of skin

Question 29

Why doesn’t skin hyperpigmentation occur in secondary adrenal insufficiency?

Answer 29

ACTH levels are also low, it is ACTH that stimulates melanocytes creating pigmentation

Question 30

Pathophysiology of secondary adrenal insufficiency?

Answer 30

Reduction of stimulation of adrenal cortex due to hypothalamus or pituitary problem

The adrenals aren’t told to make their hormones, so you become deficient

Question 31

Apart from hypothalamic-pituitary problem, what can cause secondary adrenal insufficiency?

Answer 31

Long term steroid therapy, because the axis becomes suppressed

Question 32

Investigation of secondary adrenal insufficiency?

Answer 32

ACTH test: give a synthetic form of ACTH, you should see cortisol levels rise after administration

This is in contrast to primary adrenal insufficiency where cortisol levels don’t rise

Question 33

Management of secondary adrenal insufficiency?

Answer 33

Hormone replacement: give hydrocortisone, no need for fludrocortisone

Treat underlying cause

Remove steroid therapy slowly, if this was cause