Pituitary Disorders I

Question 1

Anterior Pituitary Gland 6 major hormones

Answer 1

1. Growth Hormone (GH)
2. Adrenocorticotropin Hormone (ACTH)
3. Luteinizing Hormone (LH )
4. Folllicle Stimulating Hormone ( FSH)
5. Thyroid Stimulating Hormone (TSH)
6. Prolactin (PRL)

Question 2

Incidentally discovered Pituitary adenoma account for ____ of pituitary tumours

Answer 2

12 %

Question 3

Two Key questions you have to ask if it is a Pituitary Incidentalomas

Answer 3

Is it Hormonally active ?

Is it causing a mass effect (i.e. exerting pressure on adjacent structure) ?

Question 4

what do you do for Incidentalomas that are not hormonally active and not causing mass effect?

Answer 4

Watchful waiting (observation)

Question 5

what hormone is produced in the neurohypophysis

Answer 5

oxytocin and vasopressin

Question 6

what would be considered a secretory effect by macroadenoma

Answer 6

amenorrhea

Question 7

anatomy and physiology of pituitary:

• Pituitary is size of ___.
• Pituitary sits in _______ in sella turcica of sphenoid bone
• Pituitary is attached by stalk to hypothalamus called the ______.
• Made up of 2 lobe: anterior (glans hypophysis) and posterior (neurohypophysis)- ______ lobe is bigger

Answer 7

pea
hypophyseal fossa
infundibular stalk
anterior

Question 8

anterior pituitary secretes what hormones?

Answer 8

Luteinizing hormone, Follicle-stimulating hormone, thyrotropin, growth hormone, corticotropin, prolactin

Question 9

posterior pituitary secretes what hormones?

Answer 9

antidiuretic hormone, oxytocin

Question 10

in Anterior pituitary (adenohypophysis), The only inhibitory on constant basis is ____.

Answer 10

dopamine

Question 11

if you have mass growing on pituitary gland, it can have mass effects. Once big enough it will put pressure on surrounding structures. It can go straight up and put pressure on optic chiasm, if it does this it can cause what kind of vision loss?

Answer 11

peripheral vision loss

Question 12

Posterior lobe of pituitary will light up normally on MRI because of______.

Answer 12

vasopressin

Question 13

If pituitary gets big enough it can push brainstem back and compress third ventricle- this could cause _______.

Answer 13

hydrocephalus

Question 14

what is a Pituitary tumor or mass found incidentaly called?

Answer 14

Pituitary Incidentalomas

Question 15

For pituitary incidentaloma, what is performed to evaluate unrelated disorders?

Answer 15

CT or MRI

Question 16

clinical features of pituitary tumors

Answer 16

1. Headaches: Stretching of Dura by tumor
2. Hydrocephalus- HA, N and V, imbalance, cognitive and visual changes
3. Visual field defects: Nasal retinal fibers compressed by tumour
4. CN palsies and temporal lobe epilepsy
5. CSF fluid rhinorrhea

Question 17

If a pituitary tumor is < 10 mm (<1 cm) it is called ______.

Answer 17

microadenoma

Question 18

If a pituitary tumor is > 10 mm (>1 cm) it is called ______.

Answer 18

macroadenoma

Question 19

will a Pituitary microadenoma be causing mass effect?

Answer 19

usually not, usually macroadenoma does

Question 20

pituitary hormone excess syndromes

Answer 20

o Hyperprolactinoma
o Acromegaly
o Cushing’s Syndrome
o Thyrotropin mediated hyperthyroidism

Question 21

Prolactinoma Affects _____ cells of anterior pituitary

Answer 21

Lactotroph

Question 22

There is Representative visual field loss in a patient with a pituitary macroadenoma that compresses the_____.

Answer 22

optic system

Question 23

in prolactinoma, hypothalamic regulations is by ___ and ___.

Answer 23

Prolactin-releasing factors (PRFs) and prolactin-inhibitory factors (PIFs)

Question 24

what I the is the principal PIF regulated by the hypothalamus?

Answer 24

dopamine

Question 25

what works against PIFs?

Answer 25

Prolactin releasing factors

Question 26

Example of PRFs

Answer 26

Thyrotropin-releasing hormone (TRH), Oxytocin, EST, vasoactive intestinal peptide, and peptide histidine methionine

Question 27

_____ will stimulate lactation

Answer 27

Oxytocin

Question 28

when oxytocin stimulates lactation, it will reverse effects of _____ and stimulate lactotrophs to produce prolactin

Answer 28

dopamine

Question 29

Most common secretory adenoma

Answer 29

Prolactinoma

Question 30

Overproduction of prolactin suppresses normal gonadotropin releasing hormone- this will impair release of______.

Answer 30

LH and FSH

Question 31

In men, Impaired LH and FSH release from gonadotroph cells, leading to _____.

Answer 31

hypogonadism

Question 32

Incidence of prolactinoma

Answer 32

44 out of 100,000

Question 33

60% of the males present with macroprolactinomas, while 90% of the females present with microprolactinomas, why is this?

Answer 33

because in males it is typically with hypogonadism-> which takes longer with females it is with missed menses (amenoria) -> women are more likely to go to the doctor sooner because of missed periods and therefore catch it before it gets to be a macroprolactinoma

Question 34

Prolactinoma Prognosis

Answer 34

micro 95% do not enlarge

Question 35

is macroprolactinomas or microprolactinomas?

Answer 35

macroprolactinomas

Question 36

Prolactinoma Symptoms | in female

Answer 36

o Infertility o Menstrual disturbances o Oligo (scant bleeding), amenorrhea, irregular, delayed menarche o Galactorrhea: spontaneous or expressive o Hypoestrogenism: vaginal dryness/dyspareunia, osteoporosis/-penia

Question 37

Prolactinoma Symptoms | in male

Answer 37

``` o Hypogonadism o Decreased libido o Erectile Dysfunction o Infertility o Gynecomastia o If prepubescent: female body habitus/small testicles ```

Question 38

Other causes of Prolactonemia

Answer 38

- Drugs - Spinal cord lesions - Idiopathic causes - Pregnancy - Primary hypothyroidism - Chronic renal failure - Cirrhosis - Adrenal insufficiency - Chest wall lesions - Breast stimulation

Question 39

in prolactinoma, why should you get hormone levels and MRI?

Answer 39

to see if there is actually any mass effect or mass

Question 40

Serum prolactin level ____ in a patient with a macroadenoma greater than 10 mm in size is diagnostic of a prolactinoma.

Answer 40

>200 mcg/L

Question 41

Levels below 200 mcg/L and 10mm in size in microadenmoa suggests ___.

Answer 41

hyperprolactinemia secondary to hypothalamic compression

Question 42

Should you draw prolactin levels after you performed a breast exam?

Answer 42

no, It can cause prolactin levels to increase and then you will have falsely elevated amount.

Question 43

treatment goal for prolactinoma?

Answer 43

The goal is not to produce a normal prolactin level, but to control or shrink pituitary lesion size and restore normal gonadal function, and minimize breast glandular stimulation/galactorrhea

Question 44

first-line treatment for prolactinomas and hyperprolactinemia

Answer 44

Dopamine agonists