pituitary dysfunction

Question 1

What can go wrong with the pituitary?

Answer 1

hypofunction, hyperfunction, or a mass

Question 2

pituitary causes of hypofunction

Answer 2

mas, surgery/radiation, infiltrative lesions, infarction, genetics

Question 3

what are hypothalamic causes of pituitary hypofunction?

Answer 3

mass, radiation, infiltration, trauma, infection

Question 4

Where do mets to the pituitary usually come frome?

Answer 4

breast and lung

Question 5

What is the most common hormone-secreting pituitary adenoma?

Answer 5

prolactinoma

Question 6

Prolactinomas: clinical presentation of hormone excess

Answer 6

prolactin stimulates the mammary glands to make mil: galactorrhea
inhibits GnRH secretion and release of LH and FSH: hypogonadism and infertility
erectile dysfunction through a mechanism independent of hypogonadism

Question 7

Prolactinoma: clinical presentation of mass effect

Answer 7

extension within the pituitary can cause hormone deficiencies
if it goes upward, can compress the optic chiasm and diminish acuity
may compress CN III
may cause CSF rhinorrhea

Question 8

Non-prolactinoma causes of hyperprolactinemia

Answer 8

PREGNANCY, lactation, and intercourse
pituitary stalk damage (not enough DA)
HYPOTHYROIDISM
renal failure
medications (anti psychotics, anti depressants, opiates)

Question 9

What is the first line treatment for a prolactinoma? What are the benefits

Answer 9

dopamine agonists- this is the natural suppressor of prolactin anyway
it decreases prolactin levels, reduces tumor size, reverses hypogonadism, and can be withdrawn after 2 yrs if prolactin levels normalize

Question 10

Indications for surgery of prolactinomas

Answer 10

failure of medical therapy, desire for pregnancy with previous pregnancy complications/refusal of dopamine agonist during gestation, tumor changes during pregnancy not reversed by medical interventions
contriaindications to medical therapy, like psychiatric disease
very severe progressive visual loss

Question 11

Dx of acromegaly

Answer 11

IGF-1, oral glucose suppression test, prolactin.

Question 12

clinical presentation of acromegaly

Answer 12

facial features diffierent- look at old pics

hand/foot size, hyperhidrosis, sleep apnea, HTN, DM, colon polyps, skin tags, carpal tunnel

Question 13

treatment of acromegaly

Answer 13

surgery is only cure, but tumors can’t always be completely resected
in those cases, consider somatostatin; maybe radio therapy or dopamine analogues

Question 14

Cushing syndrome clinical presentation

Answer 14

truncal obesity, moon face, HTN, skin atrophy and bruising, DM, gonadal dysfunction, muscle weakness, hirusitism, osteoporosis, edema

Question 15

Causes of cushing’s syndrome

Answer 15

either ACTH dependent or independent
if dependent, may be pituitary or may be ectopic (like part of another cancer)
if independent, may be adrenal adenoma, carcinoma,

Question 16

How do you work up cortisol excess

Answer 16

24 hr urine free cortisol, midnight salivary cortisol, low dose dex suppression test
to determine whether an ACTH dependent excess is from pituitary or from ectopic source, try dexamethosone suppression test or inferior petrosal sinus catheterization.

Question 17

Tx of Cushing’s

Answer 17

cure and most goals can only be achieved surgically
medically, try inhibition of cortisol production: ketoconazole, metyraprone
potentially bilateral adrenalectomy