Hypopituitarism 2

Question 1

What is primary disease?

Answer 1

If the gland itself fails

Question 2

What is secondary disease?

Answer 2

No signals from hypothalamus or anterior pituitary

Question 3

What Primary hypoadrenalism?

Compared to secondary?

Answer 3

Destruction of adrenal cortex
Cortisol falls ACTH rises

Pituitary tumour damaging corticotrophs, can’t make ACTH, cortisol falls

Question 4

What can cause hypogonadism ( men + women )

Answer 4

( primary hypogonadism )

Mumps = testes
Chemo = ovaries

Question 5

Congenital causes of hypopituitarism?

Answer 5

Rare

Mutations of Tfactor genes for normal A Pit development

Deficient in GH and at least 1 more pit hormone

Question 6

Acquired causes of hypothyroidism:?

Answer 6

Adenoma = gland tumour or metastases
Radiation
Infection - meningitis
Trauma
Surgery
Hypophysitis
Pituitary apoplexy 
Peri-partum infarction. (Sheehan's syndrome)

Question 7

What is panhypopituitarism?

Answer 7

Total loss of anterior and posterior pituitary function

some dysfunction especially inflammation or surgery may cause posterior issues too

Question 8

Risk of radiotherapy induced hypopituitarism?

Answer 8

Pit + hypothalamus sensitive to radiation

depends on dose delivered to the axis

GH and gonadotrophins most sensitive
Prolactin can increase after radiation (lose dopamine)

Risk persists up to 10 years after due to the nature of chemo

Question 9

What are the presentations of hypopituitarism?

Answer 9

( FSH/LH )

• Reduced libido
• Secondary amenorrhoea
• Erectile dysfunction
• Reduced pubic hair

( ACTH )
- Fatigue

( TSH )
- Fatigue

( GH )
- Reduced Quality of Life

( PRL )
- Inability to breastfeed

Question 10

What is Sheehan’s syndrome?

Answer 10

Post partum hypopituitarism secondary to hypotension ( post partum haemorrhage = PPH )

More common in developing because of haemorrhage control

Anterior Pit enlarges in pregnancy - lactotroph hyperplasia

PPH leads to pituitary infarction

Question 11

What are the consequences of Sheehan’s syndrome?

Answer 11

• Lethargy, anorexia, weight loss ( ACTH )
• failure of lactation
• Failure to resume periods
• Posterior pit not affected

Question 12

What is the best radiological way to visualise the pituitary gland?

Answer 12

MRI ( check slide 20, the slighter darker C shape circle is the adenoma + slide 23)

Question 13

What is Pituitary apoplexy?

Answer 13

Intra-gland haemorrhage
Dramatic presentations with already adenomas
Can be precipitated by anti-coagulants

Question 14

What are the symptoms of Pituitary Apoplexy?

Answer 14

Severe sudden onset headache
Visual field defect = bitemporal hemianopia
Cavernous sinus involvement may lead to diplopia (IV, V) or ptosis (III)

Question 15

How do we diagnose hypopituitarism?

Answer 15

Dynamic Pituitary function:

To test ACTH + GH cause hypoglycaemia (<2.2mM) to cause stress and release both hormones and test cortisol

If there is an issue px will remain hypoglycaemic

Question 16

Can we treat prolactin deficiency?

Answer 16

No

Question 17

Treatment of GH deficiency?

Answer 17

Daily injection - can give right dosage for children

Measure response by:

• improvement in Quality of life
• Plasma IGF-1

Question 18

Treatment of TSH deficiency?

Answer 18

Daily levothyroxine

remember, TSH will be low so you cannot use this to adjust dose as you would in primary hypothyroidism

Aim for fT4 above the middle of the reference range

Question 19

Treatment of ACTH …

Answer 19

Replace cortisol rather than ACTH
Difficult to mimic dirunal variation of cortisol
Option 1: Prednisolone once daily AM ( 3mg )
Option 2: Hydrocortisone x3 daily ( 10/5/10mg)

Question 20

Sick day rules for patients with ACTH deficiency?

Answer 20

At risk of adrenal crisis (dizziness, hypotension, vomiting, weakness, can result in collapse and death)

Px who take Prednisolone or Hydrocortisone (replacement steriods) must be told sick day rules:

• Steroid alert pendant/bracelet
• Double steroid dose (glucocorticoid not mineralocorticoid) if fever/intercurrent illness
• Unable to take tablets (eg vomiting), inject IM or come straight to A & E

Question 21

treatment of FSH/LH deficiency in men

Answer 21

For no fertility required : replace tostesterone topically or intramuscular
Measure plasma levels
However this does not restore sperm

For fertility: Induce spermatogenesis by gonadotrophin injections
Works best if hypogonadism occurred after puberty
Measure testosterone and semen analysis ( sperm production may take 6-12 months )

Question 22

Treatment of FSH/LH deficiency in women?

Answer 22

No fertility required approach:

• Replace oestrogen
• Oral or tropical
• Will need ++ progesterone if intact uterus to prevent endometrial hyperplasia

Fertility required:
- Can induce ovulation by timed gonadotrophin injections (IVF) - LH+FSH

Question 23

Women presents with altered vision
Optician diagnoses bitemporal hemianopia
MRI shows pituitary macroadenoma
Blood tests show:

9AM cortisol High
fT4 levels low
TSH low

What is diagnosis?

Answer 23

Secondary hypothyroidism
Because TSH is low AND ft4 low.

Because TSH is low cause anterior pituitary

Question 24

How to asses is levothyroxine dose is correct

Answer 24

Aim to increase fT4 into reference range