Pituatary

Question 1

What hormones are produced by the posterior pituitary gland?

Answer 1

ADH

Oxytocin

Question 2

Which hormone prevents the production/release of prolactin?

Answer 2

Dopamine

Question 3

Which hormones are inhibited by somatastatin in the anterior pituitary?

Answer 3

Growth hormone and thyroid stimulating hormone

Question 4

Whats the most common pituitary disease?

Answer 4

Benign adenomas

Question 5

What Size are micro and macro prolactinomas?

Answer 5

<10 mm - micro

>10mm - macro (can compress over structures)

Question 6

What visual field lesion arises for a pituitary tumour?

Answer 6

Bitemporal hemianopia or
Superior quadrantanopia > inferior

PITS

Question 7

What are the symptoms of large prolactinomas in men and women?

Answer 7

Vision problems
Headaches
Low libido and infertility

Women - galactorrhea, amenorrhea, vaginal dryness and brittle bones (prolactin inhibits GNRH and therefore LH, FSH and low oestrogen.)

Men - low testosterone- erectile dysfunction, gynecomastia,

Question 8

Treatment for prolactinomas

Answer 8

Domaine agonists eg bromocriptin or cabergoline

Or surgery for macro adenomas

Maybe radiotherapy

Question 9

Causes of hyperprolactinemia?

Answer 9

Physiologic - pregnancy/lactation

Prolactinomas

Hypothyroid ( thyrotropin release hormone causes secretion of prolactin)

Medications - dopamine antagonists or oestrogen

Damage to hypothalamic pituitary stalk (trauma, tumours, brain surgery - blocks dopamine getting to pit)

Question 10

Causes of hypoprolactinemia?

Answer 10

1’ Sheehans syndrome (PPH, less blood supply causes lactotroph cells to die, pit apoplexy) causes no breast milk.

Meds - dopamine agonists

Tumours causing pressure and dysfunction of lactrotrophs, due to inflammation too.

Question 11

What’s sheehans syndrome?

Answer 11

PPH - ischemia to pit - depends or severity can cause complete hypo pit (empty sella tursica/pituitary ring sign) or mild symptoms presenting much later.

Symptoms: 
Agalactorrhea 
Amenorrhea 
Hypothyroidism 
Adrenal gland insufficiency 
Low growth hormone

Question 12

What’s the main cause of acromegaly??

Answer 12

Benign pituitary GH- producing adenoma.

Question 13

What prolactin level imply a prolactin secreting tumour?

Answer 13

> 5000mU/L

Question 14

What conditions does an increase in ACTH from a pituitary adenoma lead to?

Answer 14

Cushing’s disease - causes hypercortisol synthesis from the adrenal glands.

Nelsons syndrome - (occurs after bilateral adrenalectomy for cushings disease - leads to low cortisol and increased CRH production - enlargement of pituitary and high levels of ACTH - cortisol and aldosterone are low due to lack of Adrenal glands!)

Question 15

What are the common signs/ symptoms of cushings disease?

Answer 15

Weight gain, hypertension, irritability, excess hair growth (women), impaired immune function, red face, moon face, fatigue, purple striae, irregular menstration (women)

Question 16

In hypopit which order are they affected in?

Answer 16

GH, gonadatrophins (LH/FSH), TSH , ATCH, and prolactin

Question 17

What is kallmans syndrome?

Answer 17

Both men and women

Defect in neurons in olfactory placard loss of sense of smell AND Loss of GnRH neurons/hormones, loss of sex hormones, lack of puberty (primary and secondary sex characteristics) and infertility.

Dx: hormone levels

Question 18

What are the complications of acromegaly?

Answer 18

Hypertension
Diabetes (10%)
Cardiomyopathy
Colorectal cancer

Question 19

WhAts the diagnostic test in acromegaly?

Answer 19

Oral glucose tolerance test

Giving glucose should suppress the GH, however in acromegaly there is no suppression,

Normal GH <2mu/L with OGTT

Question 20

What’s the treatment for acromegaly?

Answer 20

Usually trans-sphenoidal surgery to remove the GH releasing adenoma.

Somatostatin analogue eg octeotide can be used as an adjunct to surgery.

Pegvisomant - GH receptor antagonist (decreases IGF-1 level)