Hypopituitarism

Question 1

Which hormone from the anterior pituitary is responsible for Growth?

Answer 1

GH (growth hormone)

Question 2

Which hormone released from the anterior pituitary is responsible for milk production?

Answer 2

Prolactin

Question 3

What is the difference between primary and secondary endocrine diseases?

Answer 3

Primary disease is where the gland itself fails (e.g thyroid gland) secondary disease is due to malfunctioning of signals from hypothalamus or anterior pituitary

Question 4

What is primary hypothyroidism and how is it measured?

Answer 4

Autoimmune destruction of thyroid gland. T3 and T4 will be low and TSH will be high

Question 5

What is secondary hypothyroidism and how is it measured?

Answer 5

Failure to make TSH e.g. due to tumour damaging thyrotrophs. Low TSH, low T3 + T4

Question 6

What hormones does ACTH regulate?

Answer 6

Cortisol. NOT aldosterone, this is through renin-angiotensin system

Question 7

What is primary hypoadrenalism and what would be the effects on blood hormone levels?

Answer 7

Destruction of adrenal cortex . Low cortisol, increased ACTH

Question 8

What is secondary hypoadrenalism and how would blood hormone levels be affected?

Answer 8

Pituitary tumour damages Corticotrophs so cannot make ACTH. ACTH and cortisol low

Question 9

What is primary hypogonadism and how would it effect blood hormone levels?

Answer 9

Destruction of testes (e.g mumps) or ovaries (e.g. chemotherapy). Testosterone/oestrogen low, increased LH and FSH

Question 10

What is secondary hypoythyroidism and how would it effect blood hormone levels?

Answer 10

Pituitary tumour damaging gonadotrophs so cannot make LH/FSH. Low FSH/LH, low testosterone/oestrogen

Question 11

Are congenital or acquired causes of hypopituitarism more common

Answer 11

Acquired

Question 12

What often causes congenital hypopituitarism?

Answer 12

Mutations of transcription factor genes needed for normal anterior pituitary hormone

Question 13

What can be seen on the MRI of someone with congenital hypopituitarism?

Answer 13

Hypoplastic (underdeveloped) anterior pituitary gland

Question 14

What is seen in the blood hormone levels of someone with congenital hypopituitarism? What does this cause?

Answer 14

Deficiency in GH and at least 1 other anterior pituitary hormone, resulting in a short stature

Question 15

List some causes of acquired hypopituitarism?

Answer 15

tumours, radiation, infection, traumatic brain injury, pituitary surgery, pituitary apoplexy, sheehans syndrome

Question 16

what is the name given for the total loss of anterior and posterior pituitary function?

Answer 16

panhypopituitarism

Question 17

describe the association between radiotherapy dosage and HPA axis damage, what is most sensitive?

Answer 17

the higher the radiation dosage the higher the risk of HPA axis damage. GH and gonadotrophins most sensitive

Question 18

Describe the process which leads to hypopituitarism in sheehans syndrome

Answer 18

a post partum haemorrhage leads to pituitary infarction, this causes post-partum hypopituitarism.

Question 19

what happens to lactotrophs during pregnancy?

Answer 19

undergo hyperplasia resulting in enlargement of the anterior pituitary

Question 20

how does sheehans syndrome present?

Answer 20

lethargy, anorexia, weight loss. failure of lactation. failure to resume menses post-delivery.

Question 21

what causes the failure to lactate seen in sheehans syndrome?

Answer 21

prolactin deficiency

Question 22

what is the best way to visualize the pituitary gland?

Answer 22

through MRI

Question 23

What is pituitary apoplexy?

Answer 23

bleeding into the pituitary or loss of blood flow to the pituitary

Question 24

how can a pituitary apoplexy be precipitated?

Answer 24

using anti-coagulants

Question 25

when does a pituitary apoplexy have the most dramatic presentaion?

Answer 25

in patients with pre-existing pituitary tumours

Question 26

how does a pituitary apoplexy present?

Answer 26

severe sudden onset headache, bitemporal hemianopia. cavernous sinus involvement may lead to diplopia (CN 4,6)

Question 27

what cautions need to be taken when interpreting basal plasma hormone concentrations? (cortisol, T4, FSH/LH, GH, ACTH)

Answer 27

Cortisol should be measured at 9am. T4 has a half life of 6 days. FSH/LH is cyclical in women. GH/ACTH are pulsatile

Question 28

how do you test for hormone levels to diagnose hypopituitarism?

Answer 28

insulin-induced hypoglycaemia stimulates GH and ACTH release, TRH stimulates TSH release and GnRH stimulates FSH/LH release. If the hormone levels dont increase post stimulation this is indiciative of hypopituitarism

Question 29

What can be seen in the radiological diagnosis of hypopituitarism?

Answer 29

posterior bright spot and empty sella turcica

Question 30

How is TSH deficiency treated?

Answer 30

levothyroxine. Aim for a fT4 above the middle of the reference range

Question 31

How is GH deficiency treated?

Answer 31

GH deficiency confirmed on dynamic pituitary function test, asses QoL. Daily injection of Genotrophin

Question 32

How is an ACTH deficiency treated?

Answer 32

Replacement of cortisol rather than ACTH using synthetic glucocorticoids.

Question 33

what are the names of the two drugs prescribed in the UK to treat ACTH deficiency?

Answer 33

Prednisolone and Hydorcortisone

Question 34

What must patients who take replacement steroids be told about?

Answer 34

Sick day rules: must wear a steroid alert pendant/bracelet. must double glucocorticoid dose if ill.

Question 35

How is FSH/LH deficiency treated in men?

Answer 35

Replace testosterone. However this does not restore sperm production, this is achieved through induction of spermatogenesis?

Question 36

How can spermatogenesis be induced?

Answer 36

gonadotrophin injections

Question 37

How is FSH/LH deficiency treated in women?

Answer 37

replace oestrogen with additional progestogen to prevent endometrial hyperplasia.

Question 38

How can ovulation be induced?

Answer 38

carefully timed gonadoptrophin injections (IVF)

Question 39

What is the usual cause of a pituitary apoplexy?

Answer 39

pre-existing adenoma