ENDO 1: Hyposecretion of anterior pituitary hormones Flashcards
List some hormones produced by the anterior pituitary gland
- FSH/LH
- Prolactin
- GH
- TSH
- ACTH
What is meant by hypopituitarism ?
Hypopituitarism =
- decreased production of:
a) ALL anterior pituitary hormones (panhypopituitarism)
OR
b) of specific hormones
congenital/acquired
How can congenital panhypopituitarism occur?
can be be due tp:
a) congenital defects
b) gene mutations (e.g PROP1 mutation)
c) usually = occurs in adults with progressive loss of pituitary secretion
for panhypopituitarism, loss of secretion happens in what order?
- Gonadotrophin
- GH
- Thyrotrophin
- Corticotrophin
What are the 3 main types of panhypopituitarism?
- simmond’s disease
- sheehan’s syndrome
- pituitary apoplexy
Give examples of causes of acquired panhypothyroidism
causes:
- infiltrative processes
- pituitary adenomas
- craniopharyngiomas
- cranial injury
- following surgery
symptoms of pan hypothyroidism = mainly due to:
a)
b)
c)
symptoms of Simmond’s Disease = mainly due to decreased :
a) thyroidal function
b) adrenal function
c) gonadal function
Give examples of symptoms of Simmond’s Disease
- secondary amenorrhoea/ oligomenorrhoea
- impotence
- loss of libido
- tiredness
- waxy skin
- loss of body hair
- hypotension
What is one key characteristic of panhypothyroidism
- insidious onset
- develops very slowly
What is one key characterisitc of Sheehan’s Syndrome ?
- specific in women
- develops very fast
Describe the onset of Sheehan’s syndrome
- develops acutely –> following post partum hemorrhage
- results in pituitary infarction
- blood loss –> causes vasoconstrictor spasm of hypophyseal arteries
- which leads to ischemia of pituitary
AND - necrosis of the pituitary
What is the difference between pituitary apoplexy and sheehan’s disease ?
- Pituitary apoplexy = not specific to women
- sheehan’s = specific to women
What is the cause of pituitary apoplexy?
due to:
- intra-pituitary infraction or hemorrhage
What is a key characteristic of pituitary apoplexy?
- rapid presentation
Describe the presentation of sheehan’s syndrome
- lethargy, anorexia, weightless = TSH/ACTH/GH deficiency
- failure to lactate = PRL deficiency
- failure to resume menses –> post delivery
How is hypopituitarism diagnosed? (biochemical diagnosis)
- Basal plasma conc of pituitary / target endocrine gland hormones
- Stimulated pituitary function test
How is hypopituitarism diagnosed? (radiological diagnosis)
- pituitary MRI
- e.g empty pituitary sella
What effect does growth hormone (somatotrophin deficiency) have on
a) children
b) adults
What effect does growth hormone (somatotrophin deficiency) have on
a) children –> short stature
b) adults –> less clear effects
What are some causes of short stature ?
- genetic (down syndrome, PW syndrome)
- emotional deprivation
- systemic disease (CF)
- malnutrition
- malabsorption (coeliac disease)
- endocrine disorders (cushing syndrome, hypothyroidism)
- skeletal dysplasias (achondroplasia)
What is dwarfism?
(achondroplasia)
describe the onset
- mutation in fibroblast growth factor 3 (FGF3)
- abnormality in growth plate chondrocytes
- results in impaired linear growth
(average size trunk BUT short arms + legs)
What is Laron dwarfism?
- mutation in the GH receptor
How can laron dwarfism be treated?
- IGF-1 treatment
- during childhood can increase height
List some causes of acquired GH deficiency in adults ?
- trauma
- pituitary tumour
- pituitary surgery
- cranial
- radiotherapy
to test for pituitary deficiency - what test might you do?
- provocation challenge
stimulation test
