Endo- pituitary disorders Flashcards
what is pituitary adenoma
benign tumour derived from cells of anterior pituitary
pituitary adenoma can be sporadic or associated with what disorder
MEN1
what size are micro-adenomas
<1cm
what size are macroadenomas
> 1cm
what symptom can macroadenomas cause due to their size
visual field defects due to compression of optic chiasma
what is the most common type of functioning pituitary adenomas
prolactin-secreting adenoma
what does excess GH cause in children and adults
children- gigantism
adults- acromegaly
what syndrome is caused by ACTH producing tumours
cushings syndrome
which visual field defect is commonly associated with pituitary adenomas
bitemporal hemianopia
what is the first line surgery treatment for pituitary adenomas
transphenoidal surgery
what is a craniopharyngioma
benign tumour that arises from the sellar/suprasella region
clinical features of craniopharyngioma
headaches and visual disturbances
hormonal imbalances
children may have growth retardation
what is hypopituitarism
inadequate production of one or more pituitary hormone as a result of damage to the pituitary gland and/or hypothalamus
most common cause of hypopituitarism amongst adults
pituitary tumours- nonfunctioning pituitary macroadenomas
hypopituitarism becomes symptomatic when what percentage of pituitary cells are damaged
more than 80%
in the posterior pituitary, decreased ADH causes what-
diabetes insipidus
what is panhypopituitarism
refers to deficiency of all anterior pituitary hormones
most common causes of panhypopituitarism
pituitary tumours
surgery
radiotherapy
what is diabetes insipidus
kidneys are unable to concentrate urine due to impaired ADH function
what does ADH stand for, where is it produced, and where is it stored
anti-diuretic hormone
produced in hypothalamus
stored in posterior pituitary
clinical features of diabetes insipidus
polydipisia
polyuria with dilute urine
main investigation for diabetes insipidus
water deprivation test
first line treatment of neurogenic diabetes insipidus
desmospray (nasally) or desmopressin oral tablets
when is IM desmopressin typically used in diabetes insipidus
in emergencies or post-pituitary surgery
what is the cause of cranial (central) diabetes insipidus
insufficient levels of circulating ADH
what is the cause of nephrogenic diabetes insipidus
characterised by renal resistance to ADH
what is acromegaly
excess of growth hormone produces gigantism in children and acromegaly in adults
clinical features of acromegaly
giant
thickened soft tissues- skin, large jaw, sweaty, large hands
snoring/sleep apnoea
hypertension, cardiac failure- early CV death
headaches
diabetes mellitus
local pituitary effects- visual fields, hypopituitarism
gold standard test for acromegaly
TT suppression test
what is the first line medication type for acromegaly
somatostatin analogues
first line investigation for acromegaly
IGF1
what is hyperprolactinaemia
abnormally high levels of prolactin in the blood
physiological causes of hyperprolactinaemia
breastfeeding
pregnancy
stress
sleep
drugs that can cause hyperprolactinaemia
dopamine antagonists eg metoclopramide
antipsychotics eg phenothiazines
less commonly- antidepressants
pathological causes of hyperprolactinaemia
hypothyroidism
pituitary adenoma
damage to stalk- iatrogenic, road accident
prolactinoma
clinical features of hyperprolactinaemia in females (early presentation)
galactorrhea (30-80%)(milky nipple discharge)
Menstrual irregulatity (25%)
Decreased lipido
Ammenorrhoea (absent menstruation)
infertility
clinical features of hyperprolactinaemia in males (late presentation)
impotence (ED)
visual field abnormal
headaches
anterior pituitary malfunction
which drugs are used to treat prolactinomas
dopamine agonists- usually cabergoline
what is the most important hormone to replace in hypopituitarism
cortisol
what is the gold standard investigation for hypopituitarism
insulin tolerance test
