Chapter 20: Pituitary

Question 1

Releases TRH, CRH, GnRH, GHRH, and dopamine into median eminence; passes through neurohypophysis on way to adenohypophysis

Answer 1

Hypothalamus

Question 2

Inhibits prolactin secretion

Answer 2

Dopamine

Question 3

Neurohypophysis

Answer 3

Posterior pituitary

Question 4

Supraoptic nuclei, regulated by osmolar receptors in hypothalamus

Answer 4

ADH

Question 5

Paraventricular nuclei in hypothalamus

Answer 5

Oxytocin

Question 6

Does not contain cell bodies

Answer 6

Neurohypophysis

Question 7

80% of pituitary gland

Answer 7

Anterior pituitary (adenohypophysis)

Question 8

What does the anterior pituitary release?

Answer 8

ADH, TSH, GH, LH, FSH, PROLACTIN

Question 9

Blood supply of anterior pituitary

Answer 9

Does not have its own direct blood supply; passes through neurohypophysis 1st (portal venous system)

Question 10

Pituitary mass compressing optic nerve (CNII) at chiasm

Answer 10

Bi-temporal hemianopia

Question 11

Almost always macro adenomas; present with mass effect and decreased ACTH, TSH, GH, LH, FSH. Tx: transsphenoidal resection

Answer 11

Nonfunctional tumors

Question 12

Tx: nonfunctional pituitary tumors

Answer 12

Transsphenoidal resection

Question 13

Contraindications to transsphenoidal approaches

Answer 13

Suprasellar extension, massive lateral extension, dumbbell-shaped tumor

Question 14

Most pituitary tumors respond to…

Answer 14

Bromocriptine (dopamine agonist)

Question 15

• MC pituitary adenoma

- Mostly microadenomas

Answer 15

Prolactinoma

Question 16

Tx: prolactinoma

Answer 16

• Most patients do not need surgery

Question 17

When do symptoms occur with prolactinoma?

Answer 17

Prolactin is usually > 150 for symptoms to occur

Question 18

Galactorrhea, irregular menses, decreased libido, infertility

Answer 18

Prolactinoma

Question 19

Tx: prolactinoma

Answer 19

Bromocriptine (safe in pregnancy) or cabergoline (both are dopamine agonists) for most or transsphenoidal resection for failure of medical management

Question 20

When do you resect macroadenomas in prolactinoma?

Answer 20

Resection with hemorrhage, visual loss, wants pregnancy, CSF leak

Question 21

HTN, DM, gigantism; can be life-threatening secondary to cardiac symptoms (valve dysfunction, cardiomyopathy)
- Usually macroadenomas

Answer 21

Acromegaly (growth hormone)

Question 22

Dx: Acromegaly

Answer 22

Elevated IGF-1 (best test), growth hormone > 10 in 90%

Question 23

Tx: acromegaly

Answer 23

Octreotide or transphenoidal resection; XRT and bromocriptine can be used as secondary therapies

Question 24

• Post partum trouble lactating (usually 1st sign)

- Can also have amenorrhea, adrenal insufficiency, and hypothyroidism

Answer 24

Sheehan’s syndrome

Question 25

What causes Sheehan's syndrome?

Answer 25

Due to pituitary ischemia following hemorrhage and hypotensive episode during childbirth

Question 26

Tx: Sheehan's syndrome

Answer 26

Hormone replacement

Question 27

Benign calcified cyst, remnants of Rathke's pouch; grows along pituitary stalk to suprasellar location

Answer 27

Craniopharyngioma

Question 28

Most frequently presents with endocrine abnormalities, visual disturbances, headache, hypocephalus

Answer 28

Craniopharyngioma

Question 29

Tx: craniopharyngioma

Answer 29

Surgery to resect cyst

Question 30

Frequent complication s/p craniopharyngioma

Answer 30

Diabetes insipidus

Question 31

What to look for in bilateral pituitary masses?

Answer 31

Check pituitary axis hormones; if OK, probably metastases

Question 32

- Occurs after bilateral adrenalectomy resulting in amenorrhea and visual problems (bi temporal hemianopia) - Hyperpigmentation

Answer 32

Nelson's syndrome Tx: steroids

Question 33

Why amenorrhea and visual problems in Nelson's syndrome?

Answer 33

Bilateral adrenalectomy -> increased CRH causes pituitary enlargement resulting in amenorrhea and visual problems (bitemporal hemianopia)

Question 34

Why hyperpgimentation in Nelson's syndrome?

Answer 34

Bilateral adrenelecotmy -> beta-MSH, a peptide byproduct of ACTH

Question 35

Adrenal gland hemorrhage that occurs after meningococcal sepsis infection, can lead to adrenal insufficiency

Answer 35

Waterhouse-Friderichsen syndrome