1. Hyposecretion of anterior pituitary hormones Flashcards
what is another name for the anterior pituitary and posterior pituitary?
anterior - adenohypophysis
posterior - neurohypophysis
list the anterior pituitary hormones
FSH/LH prolactin GH TSH ACTH
what is primary hypothyroidism?
disorder resulting in primary endocrine gland disease
what is secondary hypothyroidism?
dysfunction to the signal going to the endocrine gland
what is panhypopituitarism?
decreased production of all the anterior pituitary hormones
what is congenital panhypopituitarism?
rare, usually due to mutations of transcription factor genes needed for anterior pituitary development (e.g. PROP1 mutation)
deficient in GH and at least 1 more anterior pituitary hormone
what is acquired panhypopituitarism caused by?
- tumours: hypothalamic or pituitary (adenomas, metastases, cysts)
- radiation: GH is most vulnerable, TSH is relatively resistant
- infection: e.g. meningitis
- traumatic brain injury
- infiltrative disease: e.g. neurosarcoidosis
- inflammatory disease
- pituitary apoplexy: haemorrhage
- peri-partum infarction: Sheehan’s syndrome
what is panhypopituitarism occasionally called?
Simmond’s disease
what is secondary hypogonadism and what does it lead to?
loss of FSH/LH
- reduced libido
- secondary amenorrhoea (female)
- erectile dysfunction (male)
what is secondary hypoadrenalism and what does it lead to?
no ACTH -> no cortisol
- fatigue
what is secondary hypothyroidism a loss of and what does it lead to?
loss of TSH
- fatigue and weight gain
what is Sheehan’s syndrome?
post partum hypopituitarism:
- anterior pituitary enlarges in late stages of pregnancy
- lactotroph hyperplasia to produce prolactin as the body prepares to breast feed
- enormous loss of blood during post partum haemorrhage and BP drops (hypotension) -> pituitary receives insufficient blood supply
what does post partum haemorrhage ultimately result in?
pituitary infarction -> irreversible damage
what is the presentation of Sheehan’s syndrome
- lethargy, anorexia, weight loss (TSH/ACTH/GH deficiency)
- failure of lactation (prolactin deficiency)
- failure to resume menses post-delivery
- posterior pituitary not usually affected
what is pituitary apoplexy and in whom does it usually present?
intra-pituitary haemorrhage/ infarction
dramatic presentation in patients with pre-existing pituitary tumours (adenomas)