Pituitary Pathophysiology

Question 1

Benign tumors of pituitary/hypothalamus

Answer 1

adenomas of AP and tumors of cell rests like craniopharyngiomas and Rathke’s cleft cysts

Question 2

Infiltrative disease of pituitary

Answer 2

hemochromatosis

Question 3

Infiltrative disease of hypothalamus

Answer 3

sarcoidosis, Langerhans cell histiocytosis

Question 4

only _____ can hypersecrete pituitary hormones or fragments thereof

Answer 4

pituitary adenomas

Question 5

T/F any disease of pituitary or hypothalamus can cause deficiency of any AP hormone

Answer 5

T

Question 6

T/F any disease of pituitary or hypothalamus can cause a deficiency of vasopressin and thereby cause diabetes insipidus

Answer 6

F –> only a disease of the hypothalamus or infundibulum

Question 7

Replacement hormone for: GH

Answer 7

Somatropin –> short stature due to gh deficiency/turners/renal failure, GH deficiency in adults

Question 8

Replacement hormone for: prolactin

Answer 8

none

Question 9

Replacement hormone for: ACTH

Answer 9

hydrocortisone

Question 10

Replacement hormone for: TSH

Answer 10

thyroxine

Question 11

Replacement hormone for: LH/FSH

Answer 11

FSH and hCG

Question 12

Secretory products of the associated adenoma: somatotroph

Answer 12

GH

Question 13

Secretory products of the associated adenoma: lactotroph

Answer 13

prolactin

Question 14

Secretory products of the associated adenoma: corticotroph

Answer 14

acth

Question 15

Secretory products of the associated adenoma: gonadotroph

Answer 15

FSH (LH rarely)

Question 16

Secretory products of the associated adenoma: thyrotorph

Answer 16

TSH, alpha subunit

Question 17

T/F Peptide adenomas are recognizable early in clinical course

Answer 17

T –> somatotroph, lactotroph, corticotroph tend to be efficient in production of secretory products–> make you look “funny” early on

Question 18

Somatotroph adenomas cause clinical syndromes ____ and ____

Answer 18

gigantism if before epiphyseal closure, acromegaly after epiphyseal closure

Question 19

Acromegaly

Answer 19

growth of bones after epiphyseal closure –> jaw, nose, frontal bones, hands, feet

Question 20

Chemical profile of somatotroph adenoma

Answer 20

IGF1 elevation, lack of suppression of GH to an oral glucose load –> histologic apeparance of pituitary adenoma, immunostaining of GH

Question 21

Consequences of somatotroph adenoma

Answer 21

OA, cancer of colon, CVD, diabetes mellitus, neuropathy/carpal tunnel syndrome, sleep apnea

Question 22

T/F Acromegaly is associated with higher mortality

Answer 22

T

Question 23

Tx for somatotroph adenoma

Answer 23

surgical, radiation, pharmacological: dopamine agonist (cabergoline), somatostatin analog (octreotide, lantreotide), GH receptor antagonists (pegvisomant)

Question 24

GH receptor antagonist

Answer 24

pegvisomant

Question 25

Dopamine agonist

Answer 25

cabergoline, bromocriptine

Question 26

Somatostatin analog

Answer 26

octreotide, lantreotide

Question 27

In premenopausal women, lactotroph adenomas cause ____

Answer 27

amenorrhea/oligomenorrhea, galactorrhea

Question 28

In postmenopausal women, lactotroph adenomas cause ____

Answer 28

neurologic symptoms

Question 29

In men, lactotroph adenomas cause ____

Answer 29

hypogonadism: decreased libido, fertility, potency

Question 30

Physiologic causes of hyperprolactinemia

Answer 30

pregnancy, nursing, exercise, physical/psychological stress

Question 31

Pathologic causes of hyperprolactinemia

Answer 31

adenoma, dopamine receptor antagonists, catecholamine inhibitors, h2 antagonists, estrogens, opiates

Question 32

T/F serum prolactin levels >200 are usually adenomas (pregancy up to 400) and <200 are due to other causes

Answer 32

T

Question 33

Tx of lactotroph adenoma

Answer 33

dopamine agonist

Question 34

Clinical syndromes of corticotroph adenomas

Answer 34

Cushing's (common), neurological symptoms (uncommon)

Question 35

Do thyrotroph adenomas cause hyperthyroidism?

Answer 35

not usually but sometimes

Question 36

Tx of thyrotroph adenoma mediated hyperthyroidism

Answer 36

somatostatin analog

Question 37

Gonadotroph adenomas cause _____

Answer 37

neurological symptoms (common) --> visual field impairement, headache ; hormonal abnormality (uncommon) --> premature puberty in boys, ovarian hyperstimulation in premenopausal women

Question 38

Most common hormonal finding in gonadotroph adenoma

Answer 38

elevated intact FSH, rarely intact LH, elevated subunits of FSH/LH