23: Pituitary Path

Question 1

MC cause of pituitary hyperfunction

Answer 1

neoplasia

Question 2

males are dxed with lactotrophs when they are a much larger size - why is this?

Answer 2

females are more sensitive to lactotrophs bc they get irregular menses - men arent as affected

Question 3

5 causes of hyperprolactinemia besides adenomas

Answer 3

1. pregnancy
2. lactation
3. loss of DA (neuronal damage, drugs, mass)
4. renal failure
5. hypothyroidism

Question 4

LAM: Lactational Amenorrhea Method

Answer 4

method of birth control that relies on elevated prolactin after delivery to maintain anovulation

Question 5

Cushing Syndrome vs Cushing Disease**

Answer 5

Syndrome: hypercortisolism and its presentation
Disease: hypercortisolism specifically caused by corticotrophic adenoma

Question 6

MC cause of cushing syndrome

Answer 6

iatrogenic (drs giving glucocorticoids)

Question 7

cascade caused by GNAS mutation (assoc w pituitary adenomas)

Answer 7

Gs loses its GTPase activity -> GTP will initiate cascade with cAMP-driven cell proliferation -> adenoma (esp somatotroph)

Question 8

two H’s from posterior pituitary

Answer 8

ADH, oxytocin

Question 9

TPIT vs AIP mutations in adenomas

Answer 9

TPIT -> corticotrophic adenoma

AIP -> somatotrophic adenoma

Question 10

MC functional pituitary adenoma

Answer 10

lactotroph

Question 11

lactotroph histo

Answer 11

psammoma bodies, sparse granulation, sometimes calcification

Question 12

Tx for lactotroph adenoma

Answer 12

dopamine, surgery

Question 13

lab test for somatotroph adenoma

Answer 13

high IGF-1 that doesnt go down when given oral glucose

Question 14

bromocriptine used to treat ___

Answer 14

corticotroph adenoma / Cushing Disease

Question 15

craniopharyngioma presentation

Answer 15

hypopituitarism -> growth stunted in kids

Question 16

histo of craniopharyngioma

Answer 16

“wet” keratin, squamous ep, calcified cysts

Question 17

paraneoplastic CA that causes SIADH

Answer 17

small cell carcinoma of the lungs