EXAM #1: HYPOTHALAMUS & PITUITARY

Question 1

What are the two essential anterior pituitary hormones?

Answer 1

1) TSH

2) ACTH

Question 2

What is hypopituitarism?

Answer 2

Insufficient secretion of pituitary hormones resulting from diseases of the hypothalamus or the pituitary.

Question 3

What are the major causes of hypopituitarism?

Answer 3

1) Tumors, such as nonfunctional pituitary adenomas or craniopharyngiomas (exert pressure on adjacent pituitary cells)
2) Pituitary surgery or radiation
3) Traumatic brain injury and subarachnoid hemorrhage
4) Pituitary apoplexy (sudden hemorrhage into the pituitary gland)
5) Sheehan syndrome
6) Empty sella syndrome

Question 4

What two anterior pituitary hormones do NOT have simple feedback loops?

Answer 4

1) GH

2) Prolactin

Question 5

What is the clinical consequence of GH and Prolactin not having simple feedback loops?

Answer 5

These hormones are most likely to be in EXCESS

Question 6

What are the manifestations of excess prolactin?

Answer 6

1) Galactorrhea
2) Hypogonadism

*Elevated prolactin inhibits GnRH

Question 7

What are the manifestations of excess GH?

Answer 7

1) Giantism

2) Acromegaly

Question 8

What is prolactin essential for?

Answer 8

Lactation

Question 9

What causes hypogonadism in hyperprolactinemia?

Answer 9

Inhibition of GnRH release from hypothalamus

Question 10

What are the manifestations of hyperprolactinemia in women?

Answer 10

1) Irregular menses
2) Infertility
3) Osteoporosis

Question 11

What are the clinical manifestations of hyperprolactinemia in men?

Answer 11

1) Impotence

2) Infertility

Question 12

What is the differential diagnosis for hyperprolactinemia?

Answer 12

1) Pituitary adenoma (overproduction)
2) Decreased dopamine inhibitiory action
3) Decreased renal clearance of prolactin
4) Unknown
- Cirrhosis
- Primary amyloidosis

Question 13

What serum concentration of prolactin is diagnostic for a pituitary adenoma?

Answer 13

300

*Less than 30 is stress, greater than 100 and NOT pregnant is also an adenoma

Question 14

What drugs most commonly cause hyperporlactinemia?

Answer 14

• Verapamil
• Methyldopa
• Reglan
• Resperidone
• Haldol

Question 15

What is the most common type of pituitary adenoma?

Answer 15

Prolactinoma

Question 16

What is the treatment for a micro-prolactinoma?

Answer 16

Bromocriptine (DA agonist)

*Dopamine decreases prolactin

Question 17

What is the treatment for a macro-prolactinoma?

Answer 17

1) Bromocriptine + Tamoxifen
2) Radiation
3) Transsphenodial resection

Question 18

What is the hallmark symptom of hypoprolactinemia?

Answer 18

Failure to lactate

Question 19

What is the difference in the outcome of excessive GH secretion occurs in childhood vs adulthood?

Answer 19

Childhood= gigantism

Adulthood= acromegaly

Question 20

How is growth hormone excess diagnosed?

Answer 20

• Increased insulin-like growth factor
• MRI/CT imaging of a pituitary neoplasm.
• Growth hormone suppression test with glucose load*

*Dr. Horner, this is a MUST

Question 21

In a patient with acromegaly, what screening test should be done more frequently?

Answer 21

Colonoscopy

Question 22

How is growth hormone excess treated?

Answer 22

Surgery or radiation* + medication adjuncts

• FIRECRACKER:
• Octreotide, a somatostatin analogue that inhibits GH release from the anterior pituitary and
• Pegvisomant, a GH receptor antagonist which effectively blocks IGF-1 production.

Question 23

What type of hypothalamic tumor is more common, slow or rapid growing? Which is more destructive?

Answer 23

More common= slow growing

More destructive= rapid growing