Hypopituitarism

Question 1

What is hypopituitarism?

Answer 1

Inadequate production of one or more pituitary hormones due to damage to the pituitary gland and/or hypothalamus

Question 2

What is the most common cause of hypopituitarism in adults?

Answer 2

Nonfunctioning pituitary macroadenomas

Question 3

Name three main causes of hypopituitarism

Answer 3

1. Compression (tumors)
2. Iatrogenic (surgery/radiation)
3. Infarction/hemorrhage

Question 4

Which autoimmune condition can cause postpartum hypopituitarism?

Answer 4

Sheehan syndrome

Question 5

What is pituitary apoplexy, and why is it an emergency?

Answer 5

Sudden hemorrhage/infarction of the pituitary gland, causing

(1) headache
(2) diplopia (CN III pressure)
(3) hypopituitarism
(4) cardiovascular collapse
(5) loss of consciousness

Question 6

At what percentage of pituitary cell damage does hypopituitarism become symptomatic?

Answer 6

More than 80% damage

Question 7

What are the hormonal deficiencies seen in anterior hypopituitarism?

Answer 7

1. ↓ GH → growth failure
2. ↓ TSH → secondary hypothyroidism
3. ↓ LH/FSH → hypogonadism
4. ↓ ACTH → hypoadrenalism
5. ↓ Prolactin → unclear impact

Question 8

What deficiency causes diabetes insipidus in posterior hypopituitarism?

Answer 8

↓ ADH (arginine vasopressin deficiency)

Question 9

What is panhypopituitarism?

Answer 9

Deficiency of all anterior pituitary hormones, most commonly due to tumors, surgery, or radiotherapy

Question 10

How do pituitary tumors cause visual symptoms?

Answer 10

Compression of the optic chiasm
→ bitemporal hemianopia

Question 11

Name two key symptoms of secondary hypothyroidism

Answer 11

Weight gain, cold intolerance

Question 12

What cardiovascular symptoms can result from hypoadrenalism?

Answer 12

1. Hypotension
2. Hyponatremia
3. Cardiovascular collapse in severe cases

Question 13

How does hypogonadism present in males and females?

Answer 13

(1) Males
= Loss of libido, erectile dysfunction, loss of secondary sexual hair.

(2) Females
= Amenorrhea, loss of secondary sexual hair

Question 14

What is the classic appearance of longstanding panhypopituitarism?

Answer 14

Pallor with hairlessness
(“alabaster skin”)

Question 15

What are the main symptoms of posterior hypopituitarism?

Answer 15

Polyuria, polydipsia (diabetes insipidus)

Question 16

Why is the presence of normal gonadal function important in hypopituitarism evaluation?

Answer 16

It suggests that multiple anterior pituitary defects are unlikely

Question 17

What test is used to assess posterior pituitary function?

Answer 17

Plasma/urine osmolality

Question 18

What imaging modality is preferred for detecting pituitary adenomas?

Answer 18

MRI of the brain

Question 19

What is the initial treatment for hypopituitarism?

Answer 19

Cortisol replacement

Question 20

What is the principle of long-term management?

Answer 20

Hormone replacement and treatment of the underlying cause

Question 21

What is the first hormone that should be replaced in hypopituitarism?

Answer 21

Cortisol (hydrocortisone)

Question 22

What is the treatment for TSH deficiency?

Answer 22

Levothyroxine

Question 23

Why is cortisol replacement prioritised in hypopituitarism?

Answer 23

Because adrenal insufficiency can be life-threatening and presents similarly to Addison’s disease

Question 24

What medication is used to treat diabetes insipidus?

Answer 24

Desmopressin (nasal spray or tablets)

Question 25

What are the benefits of growth hormone replacement in adults?

Answer 25

1. Increases muscle mass
2. Strength
3. Exercise capacity
4. Bone density while reducing abdominal fat

Question 26

How is testosterone replaced in males with hypogonadism?

Answer 26

1. IM injections (Sustanon/Nebido)

Or

2. Transdermal gels (Testogel, Tostral)

Question 27

What is the definitive treatment for pituitary macroadenomas?

Answer 27

Transsphenoidal resection