Hypopituitarism

Question 1

aetiology?

Answer 1

…

Question 2

What are the signs and symptoms?

Answer 2

o Hormone deficiency

o Features of underlying cause

Question 3

what hormone deficiencies can be present?

Answer 3

o Growth hormone: central obesity, reduced strength and balance, atherosclerosis, dry wrinkly skin
o LH/FSH:
 Male: reduced libido, erectile dysfunction, reduced muscle bulk, hypogonadism (reduced hair all over, small testes, reduced ejaculate volume, reduced spermatogenesis)
 Female: reduced libido, amenorrhoea, breast atrophy, subfertility, osteoporosis, dyspareunia
o TSH: hypothyroidism
o ACTH: secondary hypoadrenalism
o Prolactin: absent lactation (RARE)

Question 4

describe the features of underlying cause

Answer 4

pituitary tumour with mass effect, hormone secretion e.g. prolactinoma, acromegaly with reduced secretion of other hormones

Question 5

what investigations are done?

Answer 5

o Basal hormone tests
o Dynamic tests
o MRI of pituitary fossa

Question 6

Describe the basal hormone tests

Answer 6

o Sex hormones: FSH and LH (low or normal), testosterone or oestradiol (low
o TFT: TSH (low or normal), T4 (low)
o Prolactin: may be elevated due to loss of inhibitory hypothalamic dopamine
o Other: IGF-1 (low), cortisol (low)

Question 7

describe the dynamic tests

Answer 7

o Short synacthen test: assess adrenal axis

o Insulin tolerance test: IV insulin given to assess response to hypoglycaemia

• Results:
  • Normal: GH >20mU/L and peak cortisol >550mU/L
  • GH deficiency: GH <9mU/L
• Requirements: water only from 22:00 the night before, 50% glucose and hydrocortisone to hand, glucose must fall below 2.2mmol/L and pt must be symptomatic when GH and cortisol levels measured
• CI: epilepsy, heart disease, adrenal failure
• Alternative: glucagon stimulation test

o Arginine and growth hormone releasing test

Question 8

what does the MRI of the pituitary fossa look for?

Answer 8

look for hypothalamic or pituitary lesion

Question 9

what is the first hormone given before anything else?

Answer 9

HYDROCORTISONE - for secondary adrenal failure before any other hormones given

Question 10

what is the management for hypothyroidism?

Answer 10

thyroxine (BUT TSH NOT useful in monitoring)

Question 11

what is the management for hypogonadism?

Answer 11

o Male: TESTOSTERONE ENANTHATE IM
o Female pre-menopausal: transdermal OESTRADIOL patches or COCP
o Gonadotrophin therapy: needed to induce fertility in males and females

Question 12

what is the management for growth hormone deficiency?

Include side effects and complications.

Answer 12

SOMATOTROPHIN self-injection (GH mimic to relieve symptoms; stop after 9m if QoL scores don’t improve by >7 points)

o SE: oedema, carpal tunnel syndrome, myalgia, congestive cardiac failure, hypertension, increased ICP (RARE), GH increases IGF-1 which is linked to increased neoplasia risk
o CI: malignancy, pregnancy, renal transplant