Week 11 - Cushing's Syndrome

Question 1

what causes cushing’s syndrome

Answer 1

• glucocorticoid excess

Question 2

what are 2 categories of causes of glucocorticoid excess

Answer 2

1. ACTH dependent

2. ACTH indpendent

Question 3

what are ACTH dependent causes of cushing’s (2)

Answer 3

• ACTH secreting pituiatry adenoma

- ectopic ACTH syndrome

Question 4

what is an ACTH secreting pituitary adenoma and how does it contribute to cushing’s

Answer 4

• pituitary tumour causes excess ACTH secretion leading to increased cortisol secretion & the cells dont respond to the negative feedback mechanism

Question 5

what is the most common of noniatrogenic cases of cushing’s

Answer 5

• ACTH secreting pituitary adenoma (68%)

Question 6

which sex does the ACTH secreting pituitary tumour occur more in

Answer 6

• 8x more frequently in women

Question 7

what is ectopic ACTH syndrome

Answer 7

• a paraneoplastic syndrome where a NON-pituitary tumour secretes ACTH
  (15% of cases)

Question 8

what is a common cause of ectopic ACTH syndrome

Answer 8

• a small cell carcinoma of the lung

Question 9

what are ACTH independent causes of cushing’s (2)

Answer 9

• adrenocortical tumour

- iatrogenic

Question 10

what is an adrenocortical tumor

Answer 10

• tumor of the adrenal cortex with tumor cells that mostly secrete cortisol
  (17%

Question 11

adrenocortical tumors can be …. (2)

Answer 11

• benign

- malignant

Question 12

what is an iatrogenic cause of cushing’s

Answer 12

• glucocorticoid excess due to glucocorticoid therapy for an inflammatory disease

Question 13

what are most manifestations of cushing’s due to (4)

Answer 13

excess:

• cortisol
• aldo
• androgens
• ACTH

Question 14

what effect does cushing’s have on a pt’s weight

Answer 14

• causes weight gain

Question 15

what is often the intial symptoms of cushing’s

Answer 15

• weight gain

Question 16

describe the manifestations of weight gain in cushings (5)

Answer 16

• central obesity
• “moonface” adipose to the face
• adipose to the neck “buffalo hump”
• adipose to the trunk
• extremities are spared = thin arms & legs

Question 17

what is central obesity in cushing’s theroized to be caused by

Answer 17

• hyperinsulinemia

Question 18

what effect does elevated cortisol during cushing’s have on the body (8)

Answer 18

• muscle wasting & fatigue
• hyperglycemia & insulin resistance
• osteoporosis
• immunosuppression
• impaired healing
• thin skin
• striae
• easily bruised skin

Question 19

what effect does elevated aldo or mimetic effects of cortisol have on the body during cushing’s (3)

Answer 19

• hypokalemia
• HTN
• metabolic alkalosis

Question 20

what effect does elevated androgens during cushings have on the body (5)

Answer 20

• increased body hair or masculine hair line
• acne
• menstrual irregularities or infertility
• hirsutism
• virilisation

Question 21

what is hirsutism

Answer 21

• excessive growth of dark, coarse hair in a male-like pattern
• hair on face, back, chest

Question 22

what is virilisation

Answer 22

• the biological development of sex difference

Question 23

how is cushings diagnosed

Answer 23

• 24 hr urine for free cortisol
• low dose dexamethasone suppression test
• CT or MRI of pituitary and/or adrenals for tumor localization

Question 24

what is treatment for cushings

Answer 24

• d/t corticosteroid use if cause is iatrogenic

- if tumor is cause, surgical removal of gland or tumour

Question 25

if you must discontinue use of corticosteroids, what should be considered

Answer 25

• must gradually taper off or switch to alternate day regimen
• never d/c abruptly

Question 26

what should nurses monitor for a pt with cushings (6)

Answer 26

• VS
• signs of infection
• daily weight (due to aldo effects)
• BG
• signs of thromboembolic phenomena
• also emotional support

Question 27

what are signs of infection to watch for (3)

Answer 27

• redness
• fever
• but may be minimal

Question 28

why is there a risk of thromboembolic phenomena in a pt with cushings

Answer 28

• due to the obesity, HTN, etc (???)