Pituitary, Thyroid, Adrenal

Question 1

Most common cause of hyperthyroidism

Answer 1

Grave’s Disease

Question 2

Describe the mechanism of Grave’s Disease

Answer 2

Autoimmune → circulating Thyroid Stimulating Immunoglobulins (TSI) → binds to TSH receptor on thyroid → makes lots of thyroid hormone

Question 3

T/F: Grave’s Disease presents as diffuse asymmetric goiter.

Answer 3

False: symmetric

Question 4

Exophthalmus and infiltrative dermopathy are specific to which disease?

Answer 4

Grave’s Disease

Question 5

Name the diseases (2)
• Focal and/or diffuse hyperplasia of thyroid follicular cells
• Activating somatic mutations of genes for TSH receptor

Answer 5

Toxic Adenoma

Toxic Multinodular Goiter

Question 6

Name the disease:

Inflammation/destruction of thyroid gland

Answer 6

Thyroiditis

Question 7

High fT4, low TSH suggests:

Answer 7

Thyroid origin of hyperthyroidism

Question 8

High fT4, high TSH suggests:

Answer 8

Pituitary origin of hyperthyroidism
(Central hyperthyroidism)

High TSH due to oversecretion by tumor

Question 9

If central hyperthyroidism, next diagnostic step is:

Answer 9

Pituitary MRI to find tumor

Question 10

If thyroiditis, next diagnostic step is:

Answer 10

Check ESR

Question 11

If Grave’s disease, next diagnostic step is:

Answer 11

Check TSI antibodies

Question 12

The best test for diagnosis of type of hyperthyroidism is:

Answer 12

Radioactive thyroid imaging

Question 13

Inflamed thyroid (thyroiditis), damaged membrane show ____ radioiodine uptake.

Answer 13

None/ ~0-2%

Question 14

Over-functioning thyroid show ____ radioiodine uptake.

Answer 14

> 25%

Question 15

Treatment for thyroiditis

Answer 15

Beta blocker ONLY

Question 16

Drug of choice for treating pregnancy and lactation patients with hyperthyroidism

Answer 16

Propylthiouracil (PTU)

Question 17

Name 2 drugs that inhibit synthesis of thyroid hormone

Answer 17

Methimazole

Propylthiouracil (PTU)

Question 18

T/F: Surgery is one of the recommendations for treating hyperthyroidism

Answer 18

False. Not recommended since it can be treated non surgically

Question 19

Treatment regimen for pregnant patient with hyperthyroidism

Answer 19

PTU for 1st trimester → then methimazole

Methimazole has teratogenic effect

Question 20

Primary adrenal insufficiency is caused by:

Deficiency in:

Answer 20

Destruction of adrenal cortex

glucocorticoid
minderalocorticoid
adrenal androgen

Question 21

All of the following are causes of Primary adrenal insufficiency EXCEPT:
A. Polyglandular failure syndromes
B. Tuberculosis/histoplasmosis
C. Sarcoma 
D. Hemorrhage

Answer 21

C. Lung/breast carcinoma

Question 22

Secondary adrenal insufficiency is caused by:

Answer 22

Deficient ACTH release from pituitary
or
Deficient hypothalamic release of CRH

Question 23

Describe the expected levels in primary adrenal insufficiency:
Cortisol:
Aldosterone:
ACTH:

Answer 23

Cortisol: low
Aldosterone: low
ACTH: high

Question 24

Describe the expected levels in secondary adrenal insufficiency:
Cortisol:
Aldosterone:
ACTH:

Answer 24

Cortisol: low
Aldosterone: normal
ACTH: low

Question 25

Primary OR secondary adrenal insufficiency: | Hyperkalemia

Answer 25

Primary

Question 26

Primary OR secondary adrenal insufficiency: | Fluid depletion

Answer 26

Primary

Question 27

Primary OR secondary adrenal insufficiency: | Hyperpigmentation

Answer 27

Primary

Question 28

Failure to suppress low dose (1 mg) overnight dexamethasone suppression test suggests:

Answer 28

Cushing's (ACTH-dependent)

Question 29

Increased ACTH suggests (2)

Answer 29

Pituitary tumor | Ectopic

Question 30

Decreased ACTH suggests (2)

Answer 30

Adrenal tumor | Exogenous

Question 31

>50% suppression in high dose DST suggests

Answer 31

Pituitary Cushing's

Question 32

No suppression in high dose DST suggests

Answer 32

ectopic Cushing's

Question 33

T/F: Primary hypothyroidism is less common than secondary hypothyroidism.

Answer 33

False. 95% are primary.

Question 34

``` All of the following are causes of primary hypothyroidism EXCEPT: A. Autoimmune B. Destructive C. Hypothalamic disorder D. Drug induced E. Hereditary ```

Answer 34

C. This is secondary hypothyroidism cause. Also pituitary disorder.

Question 35

``` All of the following are symptoms of hypothyroidism EXCEPT: A. Cold intolerance B. Weight loss C. Dry skin D. Edema ```

Answer 35

B. Weight gain

Question 36

Most common form of hypothyroidism

Answer 36

Hashimoto's Thyroidism

Question 37

Thyroid peroxidase antibodies (TPO) are found in what disease?

Answer 37

Hashimoto's

Question 38

Low fT4, high TSH suggests

Answer 38

Primary hypothyroidism: thyroid origin

Question 39

Low fT4, low TSH suggests

Answer 39

Secondary hypothyroidism

Question 40

Preferred therapy for hypothyroidism

Answer 40

Levothyroxine (T4)

Question 41

Goal of therapy for primary hypothyroidism

Answer 41

Achieve normal TSH

Question 42

Goal of therapy for secondary hypothyroidism

Answer 42

Achieve normal fT4 TSH will always be low

Question 43

T/F: Most thyroid nodules are malignant.

Answer 43

False. 95% are benign adnenomas or cysts | Only 5% are malignant

Question 44

``` Which of the following is NOT a cause of prolactin elevation? A. Pregnancy B. Secondary hypothyroidism C. Antipsychotics, metoclopramide D. Renal failure ```

Answer 44

B. Primary hypothyroidism: elevated TRH stimulates lactotrophs --> pituitary enlargement Also: prolactin secreting pituitary tumor

Question 45

Name the 2 dopamine agonists used to treat elevated prolactin

Answer 45

Bromocriptine | Cabegoline

Question 46

T/F: Nausea is a worse in Bromocriptine than Cabegoline

Answer 46

True Minimize effect by increasing dose slowly

Question 47

T/F: The most effective treatment for elevated prolactin is surgery to remove the prolactinoma.

Answer 47

False. DA agonist therapy is VERY effective. • Surgery NOT uniformly effective o High rate of recurrence o Risk of damaging healthy pituitary • Prolactinomas are the only pituitary tumors treated medically

Question 48

GnRH is secreted from ____ and stimulates ____ to secrete ___.

Answer 48

hypothalamus anterior pituitary LH, FSH

Question 49

Expected lab values in primary hypogonadism Testosterone: LH/FSH:

Answer 49

Testosterone: low | LH/FSH: high

Question 50

Expected lab values in secondary hypogonadism Testosterone: LH/FSH:

Answer 50

Testosterone: low | LH/FSH: low or low-normal

Question 51

T/F: 90% of pituitary masses are cystic lesions.

Answer 51

False. Pituitary adenoma

Question 52

What test assess for acromegaly?

Answer 52

IGF-1 produced in liver GHRH (hypothalamus) --> GH (pituitary) --> IGF-1 (liver) GH is too pulsatile and unpredictable to be accurate.

Question 53

What would expect IGF-1 to be in acromegaly?

Answer 53

Elevated Low IGF-1 would indicate no GH to stimulate IGF-1 production --> no acromegaly

Question 54

Compression of pituitary stalk by a tumor would cause ___

Answer 54

high prolactin due to interrupting flow of DA from hypothalamus that normally inhibit prolactin secretion.

Question 55

Primary adrenal insufficiency treated with:

Answer 55

glucocorticoid AND mineralocorticoid

Question 56

Secondary adrenal insufficiency treated with:

Answer 56

glucocorticoid only

Question 57

Stress dosing: Dose of glucocorticoid should be ____ when patient is sick or under increased physical stress.

Answer 57

doubled/tripled