Endocrine Flashcards
anterior pituitary
epithelial cells
blood from pituitary portal systems > hypothalamus to pituiatry
pituitary is ?
blood supply
nervous in origin
nerves supraoptic nucleus
hypothalamic factor
TRH -
dopamine
corticotrohphin
growth hormone
gonadotrophin
symptoms of pituitary disease
categorise?
hyperpituitarism - functional (benign adenoma)
hypopituitarism
deficiency of trophic hormones
local mass- expanding lesions
hyperpituitarism - functional (benign adenoma)
detected by?
immunohistochemistry
classified by basis of what hormones they contain
most common pituitary adenomas?
make how much of clinical attention?
prolactin cell
10%
4th-6th decade
prolactinomas clinical effects
amenorrhea
galactorrhea
loss of libido
infertility
growth hormones adenomas
prepuberty - gigantism
acromegaly
predisopose to DM
muscle weakness
htn
congestivce heart failure
corticotroph adenomas
cushing syndrome
HYPOpituitarism
caused by?
nonsecretory adenomas- compress and lessen function
ischaemic necrosis - sheehans syndrome (pituitary enlarges during pregnancy)
DIC, sickle cell, elevated ICP
ablation of pituitary due to surgergy or irradiation (tumout treatment)
hypopituitary signs
growth failure -
GnRH - deficient amenorrhea / infertility in women
> decreased libido
later on this can occur
TSH and ACTH
hypothyroidism
hypoadrenalism
posterior pituatry releases 2?
adh
oxytocin
ADH failure to secrete
Diabetes insipidus
siadh
local mass effect
compressed optic chiasm
bitemporal hemianopia
obstructive hydrocephalus
compression of brainstem
thyroid cells
follicle cells contain colloid
parafollucilar cells
thyroglobulin > T4/T3
TSH from anterior pituiatry actions
follicular epithelial cells use colloid in converting thyroglobulin > t4/t3
effect of t4/t3
increase basal metabolic rate
role of parafollicular cells?
synthesise calcitonin (promotes absorption of calcium by skeletal system)
t4
t3 distribution
90% inactive thyroxine T4
10% active triiodinthyronine T3
goitre
classification
enlarged thyroid
toxic
non-toxic
non-toxic goitre
little iodine
endemic in areas
derbyshire neck
non toxic goitre causes
hereditary enzymes
multinodular goitre
why do they develop dysphagia
compress structures because they get so big
thyrotoxicosis
hypermetabolic state
T4/T3
thyrotoxicosis classify
primary : Graves
secondary - TSH secreting pituitary adenoma
struma ovarii - ovarian teratoma w ectopic thyroid
exogenous thyroid intake
Graves
infiltration of tissues behind eye - exophthalmos
pretibial myxoedema
young females
graves pathogenesis
antibodies to TSH receptor and thryoglobulin
associated with other types of autoimmune diseases
sle
pernicious
addisons
hypothyroid causes
postablative
autoimmune - hashimoto’s thyroidtis
iodine deficiency
hashimotos thyroidtis histology
infiltrate of lymphoid cells
germinal centres within thyroid - autoimmune
epithelial cells become enlarged - hertle cells
neoplasms of thryoid
benign
benign
adenoma
neoplasms of thryoid
carcinoma
neoplastic clues
solitary nodules
solid > cystic
nodules in younger patients
nodules in males
cold nodules - no uptake of radioactive iodine
assessing morphology
fine needle aspiration
core biopsy / remove histology
adenoma
well formed capsule
fibrous
compression of surrounding parenchyma
predispose to carcinoma of thryoid
multiple endocrine neoplasia
ionizing radiation - atomic bomb/ chernobyl
papillary carcinoma
nuclear features
most common neoplasm of thyroid
optical clear nuclei
intranuclear inclusions
psammoma bodies- foci of calcification
presentation of papillary tumour
metastasise to lymph nodes
may present w cervical lymph node
10 year survival 90%
follicular carcinoma
follicular morphology
well demarcted with minimal invasion
usually metastasise via blood stream
> lungs
> bone
>liver
medullary carcinoma
distinctive why?
arises from parafollicular cells which secrete calcitonin
medullary origin
80% spontaneous
20% familial - MEN
calcitonin is broken down into amyloid
which cancer ?
which dye detects this?
medullary
congo red > polarised light gives rise to green colour
anaplastic
v aggressive
metastases early widely
most die within 1 year
parathyroid glands
how many?
usually 4
10% only have 3/ 5
activiyt of parathyorid
free calcium
decreased calcium = increased PTh
which causes
activated osteoclast
increased renal absorption of calcium
increased Vit d> active
increased EXCRETION of urinary phosphate
increased intestinal calcium absorption
solitary adenoma hyperparathyroidism
benign
80%
normal parathyroid is about 50%
fat
but not adenoma
osteitis fibrosa cystica
primary hyperparathyroidism causes
bone resorption w thinning of cortex and cyst formation
= may lead to fractures
= fracture
primary hyperparathyroidism
renal effects
stones
obstructive uropathy
primary hyperparathyroidism
GI
constipation
pancreatitis
gallstones
primary hyperparathyroidism
CNS effects
alterations
depression
lethargy
and fits
primary hyperparathyroidism
neuromuscular effects
weakness
primary hyperparathyroidism
Uro effects
polyuria and polydipsia
primary hyperparathyroidism
useful mnemonic for symptoms
painful bones
renal stones
abdominal groans
psychic moans
secondary hyperPTH
chronic depression of serum calcium
causes persistent stimulation
> enlarged glands
widespread bone disease
renal failure is a big cause
hypoPTH
surgical ablation
congenital absence
autoimmune
signs of HypoPTH
neuromuscular irritibility : tingling tetany
cardiac arrhythmia
fits
cataracts
adrenal gland
cortex surrounded by medulla
zona glomerulosa -
aldosteone
zona fasciculata
glucocorticoids
zona reticularis
androgens
glucocorticoids
medulla
noradrenaline
cushing syndrome
most cases caused by exogenous steroids
cushing disease
primary hypothalamic pituitary disease with increased ACTH - cushing disease
cushing syndrome
secretion of ectopic ACTH by what tumour?
most commonly
small cell carcinoma of lung
non-endocrine
bilateral hyperplasia
iatrogenic cushing syndrome
adrenals
atrophy
hyperaldosteronism
primary - Conn’s syndrome
bilateral hyperplasia
htn and HYPOkalaemia
waterhouse-friderichson syndrome
a group of symptoms caused when the adrenal glands fail to function normally. This occurs as a result of bleeding into the glands
adrenal insufficiency
split by
acute: sudden withdrawal of steroids
haemorrhage (neonates)
sepsis w DIC
chronic
> autoimmune: addison’s
TB
HIV
haemchromatosis
sarcoid
adrenal medulla
secretes catecholamines in response to signals from the sympathetic nervous system
> phaeochromocytoma
Neuroblastoma
phaeo
rule of 10
secrete catecholamines
10% genetic syndrome
MEN, von Hippel
10% bilateral
10% malignant
Multiple endocrine neoplasia
inherited
proliferative lesions
multiple endocrine organs
tumours in MEN
occur at a younger age than sporadic tumours
arise in multiple endocrine organs
multifocal in one organ
preceded by hyperplasia
usually more aggresive than sporadic tumours
parafolliculary c cells which carcinoma
medullary
