Endo pathologies Flashcards
pituitary
prolactinoma acromegaly gigantism corticotropic pituitary adenoma hypopituitarism diabetes insipidus
thyroid
graves disease hasimotos thyroiditis endemic hypothryoidism cretinism myxoedema hyperthyroidism hypothryroidism
adrenal
pheochromocytonoma
cushings syndrome
CAH
addisons
parathyroid
hyperparathyroidism
osteoporosis
disorders of anterior pituitary
over stimulation
under stimulation
flat pig
Hypothalamic central diabetes insipidus
disorders of posterior pituitary
deficiency in vasopressin secretion
Hypothalamic central diabetes insipidus causes
head trauma
infections
tumours
dehydration
nephrogenic diabetes insipidus
disorders of posterior pituitary
kidney is insensitive to vasopressin
nephrogenic diabetes insipidus causes
renal disease
mutations in vasopressin receptor gene
mutations in gene encoding aquaporin 2
how common are pituitary tumours
1 in 4 can get pituitary microadenoma (usually benign) 4700 diagnosed a year in UK 12% of all brain tumours found in young/ middle-aged found through routine autopsies
signs and symptoms of pituitary tumours caused by
change in circulating pituitary hormone levels
direct pressure from tumour
micro-adenoma
<1cm
Macro-adenoma
> 1cm
pituitary tumours
secreting or non-secreting
usually benign
can cause hypopituitarism which is a reduction in hormone secretion
secreting tumours release an excess of
PRL - most common GH ACTH FSH/ LH TSH - least common
prolactinomas
most common type of secreting tumour
from lactotrophs
usually more common in females (periods stop)
can cause inferitility in males and females
adenomas of the pituitary somatotropes
excess GH leads to gigantism in children or acromegaly in young adults
differences due to fusion of growth plates that will stop long bones from growing and cause the symptoms of acromegaly and stop gigantism
what is acromegaly
over-secretion of growth hormone in an adult
GH oversecretion persists after bone fusion ends
acromegaly symptoms
enlargement of the head, hands, lips, jaw, tongue and feet
excessive sweating, headaches, visual loss
corticotropic adenomas of the pituitary
micro-adenoma
excess production of ACTH leads to Cushing’s
ACTH works on the adrenal gland to release cortisol
produce excessive amount of POMC gene such as MSH and endorphins
symptoms of Cushing’s
hyperglycaemia
loss of muscle mass
thin limbs
fat storage in abdomen, face and shoulders
osteoporosis
sodium and fluid retention due to excess aldosterone
orange skin pigmentation
signs and features of cushing’s
moon face
red cheeks
truncal obesity
abdominal striae
gonadotropic adenomas
6% of pituitary tumours
large tumours and associated with local pressure and mass effects
gonadotropic adenomas in MEN
rise in FSH
little or no change in LH
gonadotropic adenomas in WOMEN
neither FSH or LH raised
hard to treat
diagnosis of pituitary tumours
non-secreting effects vision secreting depends on what hormone is being released optical test blood test urine samples CT scan MRI PET scan
CT scan
not preferred as they cant detect macroadenomas due to low resolution
MRI
radio waves
builds cross-section of the brain
sensitive enough to find tumours that are >3mm
- Observation (managing a pituitary tumour)
repeat MRI
monitor hormone function if not compressing optic nerve
- Dopamine receptor antagonists (managing a pituitary tumour)
bromocriptione cabergoline prolactinoma inhibits PRL secretion after treatment levels return to normal after 8 weeks growth of tumour arrested or reversed
- Somatostatin analogues (managing a pituitary tumour)
octreotide
lanreotide
adenoma of somatotrophs
inhibit GH secretions
- Irradition of tumour (managing a pituitary tumour)
more common post surgery
- Surgey (managing a pituitary tumour)
transsphenoidal surgery
Herman Schoffler conducted it but patient only survived 10 weeks
Harvey Cushing - an oral incision and submucosal resection of the septum (7.5% death rate)
called transfrontal surgery
goitre
enlargement of thyroid gland from HYPER and HYPO
autoimmune thyroid disease
Grave’s disease- hyper
hashimotos thryoiditis - hypo
graves disease
autoantibodies thyroid stimulating autoantibodies (TSAb) binds to TSH receptor interacts with binding domain mimics TSH increases thyroxine
negative feedback of graves disease
shuts off TSH production in the anterior pituitary
thyroid gland continues function as TSAb synthesis is not suppressed
hyperthyroidism
signs and symptoms of graves
weight loss hyperactivity sweaty warm skin large appetite intolerance to heat
treatment for graves
thionamide drugs - block T4 synthesis by inhibiting TPO enzyme which reduces amount of T3 made
surgery to remove thyroid gland and take replacement T4 tablets
radioactive iodide
thionamide drugs
carbimazole
methimazole
hypothyroidism
thyroid failure
autoimmune destruction (hashimotos)
diet insufficient
peripheral cells cannot convert T4 to T3
Symptoms of hypothyroidism
dry, cool skin intolerance to cold hair loss decreased metabolic rate increased weight
hypothyroidism can lead to endemic iodine deficiency
lack of iodine in diet
ingestion of goitrogens
cretinism of newborn
