Cushing's Syndrome (0)

Question 1

What does Cushing’s syndrome refer to?

Answer 1

Signs and symptoms that develop after prolonged abnormal elevation of cortisol

Question 2

What does Cushing’s disease refer to?

Answer 2

Specific condition where pituitary adenoma secretes Excessive ACTH. CAUSES Cushing’s

Question 3

Cushing’s syndrome is always caused by Cushing’s disease. True or False?

Answer 3

FALSE

Question 4

Way to remember presentation of Cushing’s syndrome?

Answer 4

Picture patient with very round middle and thin, weak limbs who is havin effects of XS stress hormone

Question 5

Presentation of Cushing’s syndrome?

Answer 5

• Moon face
• Central obesity
• Abdominal striae
• Buffalo hump
• Proximal limb muscle wasting
• Hypertension
• Cardiac hypertrophy
• Hyperglycaemia
• Insomnia
• Depression
• Osteoporosis
• Easy bruising and poor healing of skin

Question 6

Causes of Cushing’s syndrome?

Answer 6

Exogenous roids
Cushing’s disease (pituitary adenoma releasing XSive ACTH)
Adrenal adenoma
Paraneoplastic Cushing’s

Question 7

What is paraneoplastic Cushing’s?

Answer 7

When XS ACTH is released from cancer (non-pituitary adenoma) & stimulating XSive cortisol release-> ectopic ACTH (SCLC)

Question 8

Common cause of paraneoplastic Cushing’s?

Answer 8

SCLC

Question 9

Best investigation for Cushing’s?

Answer 9

Dexamethasone suppression tests

Question 10

What occurs in a dexamethasone suppression test?

Answer 10

Initially giving patient “low dose test”. If normal, exclude Cushing’s
If abnormal then high dose test performed to differentiate underlying cause

Question 11

Low dose dexamethasone test normal result?

Answer 11

For dexamethasone to suppress release of cortisol by effecting negative feedback on hypothalamus & pituitary

• Hypothalamus responds by reducing CRH output
• Pituitary responds by reducing ACTH output
• Lower CRH and ACTH levels result in low cortisol level

Question 12

Abnormal result in low dose dexamethasone test?

Answer 12

If cortisol isnt suppressed (Seen in Cushing’s syndrome)

Question 13

High dose dexamethasone test dose?

Answer 13

8mg

Question 14

Low dose dexamethasone test dose?

Answer 14

1mg

Question 15

Response to high dose dexamethasone test for Cushing’s disease?

Answer 15

Pituitary still shows some response to negative feedback & 8mg of dexamethasone is enough to suppress cortisol

Question 16

Response to High dose dexamethasone test in Adrenal Adenoma?

Answer 16

Cortisol is NOT suppressed
ACTH IS suppressed due to negative feedback on hypothalamus & pituitary gland

Because cortisol production is independent from pituitary

Question 17

Ectopic ACTH (SCLC) response to high dose dexamethasone

Answer 17

Neither cortisol or ACTH will be suppressed

Because ACTH production is independent of hypothalamus or pituitary gland

Question 18

Cortisol reaction to high dexa in pituitary adneoma?

Answer 18

Suppressed

Question 19

Cortisl reaction to high dexa in ectopic ACTH?

Answer 19

Not suppressed

Question 20

Cortisol reaction to high dex in adrenal adenoma?

Answer 20

Not suppressed

Question 21

ACTH reaction to high dex in pituitary adenoma?

Answer 21

Suppressed

Question 22

ACTH reaction to high dex in adrenal adenoma?

Answer 22

Suppressed

Question 23

ACTH reaction to high dex in ectopic ACTH?

Answer 23

Not suppressed

Question 24

Alternative investigation in Cushing’s as Dexamethasone test alternative?

Answer 24

24h urinary free cortisol

Question 25

Other investigations for Cushing’s?

Answer 25

FBC (^ WBCs) (Decreased K+?)
MRI Brain for pituitary oedema
Chest CT for SCLC
Abdo CT for adrenal tumours

Question 26

Treatment aim of Cushing’s?

Answer 26

Remove underlying cause

Question 27

Management options for Cushing’s?

Answer 27

• Trans-sphenoidal removal of pituitary adenoma
• Surgery removal of adrenal tumour
• Surgical removal of tumour producing ectopic ACTH

Question 28

Alternative treatment of Cushing’s syndrome?

Answer 28

Remove adrenal glands & give patient replacement roids for life