Pituitary

Question 1

most common form of primary endocrine hyperfunction

Answer 1

neoplasia!!

*except thyroid

Question 2

pituitary embryologic origin

Answer 2

Rathkes pouch

Question 3

posterior pituitary histo

Answer 3

axonal neurons
supportive pituicytes (neuroglial cells)

Question 4

anterior pituitary histo

Answer 4

acidophils (GH, prolactin)
basophils (TSH, LH/FSH, ACTH)
chromophobe

Question 5

mass effect of pituitary lesions

Answer 5

increased ICP resulting in:
headaches
N/V
HTN
bradycardia
resp depression
papilledema
bilateral temporal hemianopsia
pituitary apoplexy (hemorrhage)

Question 6

types of pituitary adenomas

Answer 6

non-functional - cause mass effect

functional - cause hormone excess

Question 7

most common functional pituitary adenoma

Answer 7

lactotroph adenoma/prolactinoma

Question 8

prolactinoma presentation in females

Answer 8

menstrual irregularities
galactorrhea
diminished libido
infertility
mass effect

Question 9

prolactinoma presentation in males

Answer 9

decreased libido
decreased sperm count
mass effect

Question 10

classification of prolactinomas

Answer 10

sparsely granulated - most common

densely granulated - rare

Question 11

histo progression of prolactinomas

Answer 11

stromal hyalinization with psammoma bodies

dense calcifications = pituitary stone

Question 12

prolactinoma tx

Answer 12

dopamine agonists - bromocriptine, cabergoline

surgery

Question 13

causes of hyperprolactinemia in absence of adenoma

Answer 13

pregnancy
lactation
loss of dopamine (damage or drugs)
renal failure
hypothyroidism

Question 14

somatotroph adenoma presentation

Answer 14

gigantism (children)

acromegaly (adults)

Question 15

features of acromegaly

Answer 15

enlargement of face and hands
protruding jaw
enlarged nose
thickened lips
joint pain/limited mobility
enlarged viscera
cardio complications shorten lifespan

Question 16

acromegaly diagnostic testing

Answer 16

get serum IGF-1

if elevated, oral glucose tolerance test for GH response (glucose should inhibit GH release)

Question 17

corticotroph adenoma

Answer 17

causes hypercortisolism and Cushing syndrome

Question 18

Cushing syndrome

Answer 18

hypercortisolism resulting in:
obesity
DM
hirsutism
adrenal hyperplasia
moon face
buffalo hump

Question 19

Cushing disease

Answer 19

increased secretion of pituitary ACTH secondary to adenoma

results in hypercortisolism

Question 20

causes of Cushing syndrome

Answer 20

exogenous cortisol (glucocorticoid administration)
small cell carcinoma
pancreatic CA
neural tumors

Question 21

Cushing syndrome diagnostic testing

Answer 21

check ACTH level:
if low –> get CT/MRI of abdomen
if high –> get MRI of brain

Question 22

dexamethasone suppression test

Answer 22

diagnostic test to determine corticotroph adenoma vs ectopic tumor vs adrenal hyperplasia

Question 23

pituitary adenoma response to dexamethasone suppression test

Answer 23

elevated urine/serum cortisol
elevated corticotropin
low dose dexamethasone does not suppress
high dose dexamethasone DOES suppress

Question 24

ectopic corticotropin response to dexamethasone suppression test

Answer 24

elevated urine/serum cortisol
elevated corticotropin
low does dexamethasone does not suppress
high dose dexamethasone does not suppress

Question 25

adrenal tumor/hyperplasia response to dexamethasone suppression test

Answer 25

elevated urine/serum cortisol suppressed corticotropin low does dexamethasone does not suppress high dose dexamethasone does not suppress

Question 26

hypercortisolism tx

Answer 26

somatostatin analogs bromocriptine surgical excision

Question 27

typical presentation of gonadotroph adenoma

Answer 27

mass effect! also called "silent" or "null cell" adenomas

Question 28

which transcription factor is associated with most functioning pituitary adenomas?

Answer 28

PIT-1

Question 29

which transcription factor is associated with corticotroph adenoma?

Answer 29

TPIT

Question 30

which somatic gene mutation is associated with most pituitary adenomas?

Answer 30

GNAS *cAMP driven cell proliferation

Question 31

which somatic gene mutation is associated with corticotroph adenomas

Answer 31

USP8 *EGFR upregulation

Question 32

which familial gene mutation predisposes individuals to pituitary adenomas?

Answer 32

AIP (FIPA)

Question 33

rathke's cleft cyst

Answer 33

cystic mass derived from Rathke's pouch can expand and compress normal pituitary can rupture and cause inflammation/infection

Question 34

adolescent craniopharyngioma

Answer 34

most often adamantinomatous growth retardation and hypopituitarism

Question 35

adult craniopharyngioma

Answer 35

papillary increased ICP and hypopituitarism

Question 36

etiology of craniopharyngioma

Answer 36

derived from Rathke's pouch remnants

Question 37

histo of craniopharyngioma

Answer 37

squamous epithelium "wet" keratin calcified cyst

Question 38

primary empty sella syndrome

Answer 38

CSF leaks into the sella and compresses the pituitary

Question 39

secondary empty sella syndrome

Answer 39

pituitary expands and infarcts within the sell, leaving an empty space

Question 40

common causes of hypopituitarism

Answer 40

tumors (craniopharyngioma, rathke's cyst, gliomas) empty sell syndrome sheehan syndrome

Question 41

pathophysiology of sheehan syndrome

Answer 41

pituitary enlarges during pregnancy which makes it susceptible to compression, ischemia and avascular necrosis

Question 42

what predisposes pregnant women to sheehan syndrome?

Answer 42

small sella turcica autoimmunity coagulation abnormalities severe postpartum hemorrhage

Question 43

diabetes insipidus

Answer 43

ADH deficiency central vs nephrogenic

Question 44

presentation of DI

Answer 44

increased serum osmolality/hypernatremia dilute, excessive urine polyuria

Question 45

how do you determine central vs nephrogenic DI?

Answer 45

administer desmopressin does the kidney respond? yes - central no - renal

Question 46

SIADH causes

Answer 46

small cell carcinoma of the lung TBI/subarachnoid hemorrhage drugs (SSRIs)

Question 47

SIADH presentation

Answer 47

``` decreased serum osmolality/hyponatremia concentrated urine (hypernaturia) AMS muscle weakness seizures ```

Question 48

when does thirst present, DI or SIADH?

Answer 48

BOTH DI - legit need to replace fluids SIADH - effect of ADH on brain results in inappropriate thirst