Pituitary Gland

Question 1

What are the physiological causes of pituitary enlargement?

Answer 1

Puberty
3rd trimester of pregnancy
Early postpartum

Question 2

True or False: Pituitary growth (adenoma) causes hyperpituitarism?

Answer 2

False
Large growths disrupt the normal pituitary gland function and cause hypopituitarism

Growths that involve the pituitary stalk (infundibulum) also disrupt normal pituitary function as blocks releasing hormones from hypothalamus

Question 3

In severe cases, pituitary growth can cause what kind of visual field defect?

Answer 3

Loss of peripheral vision (in severe cases bitemporal hemianopsia)

Question 4

What are some less common mass effects of pituitary growth?

Answer 4

Less common:
Double vision (diplopia), from compression of cranial nerves III, IV or VI in the cavernous sinus
Facial numbness, from compression of cranial nerves V1 and V2

Rarely:
Rhinorrhea (runny nose) from CSF leak
Seizure, mental changes (lateral extension to temporal lobe)

Question 5

Describe the progressive symptoms of hypopituitarism:

Answer 5

Go Find The Adenoma Please

GH deficiency and FSH/LH deficiency appear early, followed by TSH and ACTH deficiency, Prolactin deficiency least common

Question 6

What are the effects of hypogonadotropic hypogonadism in females and males?

Answer 6

Women- Symptoms of estrogen deficiency
Amenorrhea (lack of periods), infertility, dyspareunia (painful intercourse), breast atrophy, loss of secondary sexual hair

Men- Symptoms of testosterone deficiency
Poor libido (sex drive), erectile dysfunction, infertility, fatigue, soft testicles, loss of secondary sexual hair, loss of muscle mass/strength

Both: Loss of bone mineral density

Question 7

What are the effects of GH deficiency in adults and children, and do we tests for deficiency?

Answer 7

Adults:
Reduced muscle mass
Abdominal obesity
Lipid disorder
Low bone mass

Child:
Short stature

Screening test is low IGF-1. Measuring GH is unreliable as pulsatile, fluctuates rapidly and widely.

Question 8

What are the effects of central hypothyroidism on adults and children?

Answer 8

Adults: 
Decrease in energy
Constipation
Sensitivity to cold
Dry skin
Weight gain

Children:
Growth restriction
Weight gain, esp relative to height

Question 9

What are the effects of central/secondary adrenal insufficiency?

Answer 9

Symptoms of cortisol deficiency:
Weakness
Tiredness, fatigue
Dizziness on standing
Pallor (not hyperpigmented) - pale appearance 
Hypoglycemia
Unintentional weight loss
Loss of appetite, nausea

Question 10

What are some dynamic testing for potential hypopituitarism?

Answer 10

Insulin Tolerance Test= Gold standard to confirm GH deficiency and ACTH deficiency
Give insulin to provoke hypoglycemia
Hypoglycemia should stimulate GH to increase and ACTH to increase cortisol levels

Cosyntropin (ACTH) stimulation test
Cosyntropin is a synthetic ACTH, looks to document hypothalamic-pituitary-adrenal status

GnRH stimulation test for LH, FSH is rarely done
TRH stimulation test for TSH is rarely done

Question 11

List causes of hypopituitarism:

Answer 11

• = common
• 1. Pituitary and parapituitary tumors
• 2. Iatrogenic: Surgery of pituitary tumor, Radiation therapy (treat various intracranial tumors, including pituitary)
• 3. Trauma

4. Drugs (opioids, high dose steroids)
5. Vascular (pituitary apoplexy) (infarction or hemorrhage)
6. Infiltrations, eg. sarcoidosis, hemochromatosis
7. Infections, eg. tuberculosis
8. Inflammation, eg. autoimmune hypophysitis
9. Sheehan’s syndrome (post partum pituitary gland hemorrhage)

Question 12

Why do we need to initiate glucocorticoid therapy before thyroid therapy?

Answer 12

Thyroid hormone increases the metabolism of cortisol and may lead to acute adrenal crisis if there is existing cortisol deficiency

Question 13

What are common mass effects of the pituitary tumor?

Answer 13

mass effect cause headache, vision loss, nausea, vomiting, or fatigue.