Week 11 - Cushing's Syndrome Flashcards
what causes cushing’s syndrome
- glucocorticoid excess
what are 2 categories of causes of glucocorticoid excess
- ACTH dependent
2. ACTH indpendent
what are ACTH dependent causes of cushing’s (2)
- ACTH secreting pituiatry adenoma
- ectopic ACTH syndrome
what is an ACTH secreting pituitary adenoma and how does it contribute to cushing’s
- pituitary tumour causes excess ACTH secretion leading to increased cortisol secretion & the cells dont respond to the negative feedback mechanism
what is the most common of noniatrogenic cases of cushing’s
- ACTH secreting pituitary adenoma (68%)
which sex does the ACTH secreting pituitary tumour occur more in
- 8x more frequently in women
what is ectopic ACTH syndrome
- a paraneoplastic syndrome where a NON-pituitary tumour secretes ACTH
(15% of cases)
what is a common cause of ectopic ACTH syndrome
- a small cell carcinoma of the lung
what are ACTH independent causes of cushing’s (2)
- adrenocortical tumour
- iatrogenic
what is an adrenocortical tumor
- tumor of the adrenal cortex with tumor cells that mostly secrete cortisol
(17%
adrenocortical tumors can be …. (2)
- benign
- malignant
what is an iatrogenic cause of cushing’s
- glucocorticoid excess due to glucocorticoid therapy for an inflammatory disease
what are most manifestations of cushing’s due to (4)
excess:
- cortisol
- aldo
- androgens
- ACTH
what effect does cushing’s have on a pt’s weight
- causes weight gain
what is often the intial symptoms of cushing’s
- weight gain
describe the manifestations of weight gain in cushings (5)
- central obesity
- “moonface” adipose to the face
- adipose to the neck “buffalo hump”
- adipose to the trunk
- extremities are spared = thin arms & legs
what is central obesity in cushing’s theroized to be caused by
- hyperinsulinemia
what effect does elevated cortisol during cushing’s have on the body (8)
- muscle wasting & fatigue
- hyperglycemia & insulin resistance
- osteoporosis
- immunosuppression
- impaired healing
- thin skin
- striae
- easily bruised skin
what effect does elevated aldo or mimetic effects of cortisol have on the body during cushing’s (3)
- hypokalemia
- HTN
- metabolic alkalosis
what effect does elevated androgens during cushings have on the body (5)
- increased body hair or masculine hair line
- acne
- menstrual irregularities or infertility
- hirsutism
- virilisation
what is hirsutism
- excessive growth of dark, coarse hair in a male-like pattern
- hair on face, back, chest
what is virilisation
- the biological development of sex difference
how is cushings diagnosed
- 24 hr urine for free cortisol
- low dose dexamethasone suppression test
- CT or MRI of pituitary and/or adrenals for tumor localization
what is treatment for cushings
- d/t corticosteroid use if cause is iatrogenic
- if tumor is cause, surgical removal of gland or tumour
if you must discontinue use of corticosteroids, what should be considered
- must gradually taper off or switch to alternate day regimen
- never d/c abruptly
what should nurses monitor for a pt with cushings (6)
- VS
- signs of infection
- daily weight (due to aldo effects)
- BG
- signs of thromboembolic phenomena
- also emotional support
what are signs of infection to watch for (3)
- redness
- fever
- but may be minimal
why is there a risk of thromboembolic phenomena in a pt with cushings
- due to the obesity, HTN, etc (???)
