Endocrinology I

Question 1

which hormone is responsible for directly stimulating tissue growth?

Answer 1

IGF-1 whose secretion is stimulated by GH

Question 2

what type of cell makes up most of the pituitary gland?

Answer 2

somatotroph (50%)

Question 3

what type of cell is the least abundant in the pituitary gland?

Answer 3

thyrotrophs (<10%)

Question 4

what is the most common type of hormone secreting pituitary tumor?

Answer 4

prolactin

Question 5

how would you classify most pituitary tumors?

Answer 5

non-malignant (benign)

• non functioning (don’t affect hormone levels)
• hyperfunctioning

Question 6

what is the size of a microadenoma?

Answer 6

<1cm

Question 7

what is the size of a macroadenoma?

Answer 7

> 1cm

Question 8

what are common signs and sxs that go along with pituitary tumors?

Answer 8

1. visual field defects
2. N/V
3. H/A
4. hormone specific sxs

Question 9

what is the most common type of pituitary tumor overall?

Answer 9

non-functioning

micro>macro

Question 10

what is unique about LH/FSH secreting tumors?

Answer 10

the hormones secreted are not effective, therefor do not produce any clinical manifestations

Question 11

what is the most common way that microadenomas are found?

Answer 11

incidental finding from a scan that was taken for another reason

Question 12

what is included in the initial pituitary work up?

Answer 12

1. all ant. pit. hormones
2. target organ hormones (free T4, cortisol, sex hormones, IGF-1)
3. MRI of pit and hypothalamus (w/contrast)-NOT of the WHOLE BRAIN
4. ophthalmology referral for pt with macroadenoma and field defects

Question 13

when is surgery recommended?

Answer 13

1. symptomatic tumors

2. macroadenomas

Question 14

why does reglan cause hyperprolactinemia?

Answer 14

it is a dopamine antagonist

-dopamine secretion inhibits prolactin release

Question 15

what is a normal prolactin level?

Answer 15

> 30

Question 16

what action does GH oppose?

Answer 16

insulin action

is considered to be diabetogenic

Question 17

hypogylcemia will do what to GH?

Answer 17

stimulate it

Question 18

hyperglycemia will do what to GH?

Answer 18

suppress it

Question 19

what are the nine I’s of hypopituitarism?

Answer 19

invasive (*pit tumor)
infarction (*CVA)
injury (*brain trauma)
invasive
immunologic
iatrogenic (*post surgical, radiologic)
infetious
idiopathic
isolated

Question 20

which gland is the problem in primary hypothyroidism?

Answer 20

thyroid gland

Question 21

which gland is the problem in secondary hypothyroidism?

Answer 21

pituitary

Question 22

how would you describe a diffuse goiter?

Answer 22

whole gland enlargement

-Grave’s dz, Hashimotos, endemic goiter

Question 23

how would you describe a heterogenous goiter?

Answer 23

multinodular goiter

Question 24

how would you describe a solid nodule goiter?

Answer 24

benign nodules vs cancer?

solitary nodule

Question 25

which thyroid tests are most commonly used?

Answer 25

TSH (thyrotropin) | free T4

Question 26

why do we test for free T4?

Answer 26

results of a total T4 will change in connection with albumin levels

Question 27

what could increase TBG levels?

Answer 27

estrogen | OCP/Pregnancy

Question 28

when would you use thyroglobulin level test?

Answer 28

post thyroid cancer treatment follow up

Question 29

when would you use calcitonin?

Answer 29

screening for medullary carcinoma

Question 30

what imaging study is the best one to determine thyroid anatomy?

Answer 30

ultrasound | -determines size of nodule and/or if it is cystic or solid

Question 31

what are the inactive metabolites of epi and norepi?

Answer 31

metanephrine | normetanephrine

Question 32

what is the 10% rule of pheochromocytoma?

Answer 32

``` bilateral malignant extra adrenal pediatric familial ```