Endocrinology Peer Teaching Flashcards
cushings is too much/too little _______
cushing’s is too much cortisol
conn’s syndrome is too much/too little _______
conn’s syndrome is too much aldosterone
addison’s syndrom is too much/too little ________
addison’s sundrome is too little cortisol and too little aldosterone
diabetes insipidus is too muc/too little _______
diabetes insipidus is not enough ADH
siADH is too much/too little _______
siADH is too much ADH
describe the anatomy of the pituitary gland
it lies just inferior to the optic chiasm. it is connected to the hypothalamus via the pituitary stak (infundibulum)
draw the flow chart for anterior pituitary hormones and their target organs and effects
are men or women more affected by thyroid conditions?
F>M
when does hyperthyroidism mainly present
20-40yrs
what is most hyperthyroidism caused by
2/3 is graves disease
what are some non-graves causes of hyperthyroidism
toxic multinodular goitre
toxic thyroid adenoma
iodene excess
8 symptoms of hyperthyroidism
diarrhoea
weight loss
heat intolerance
palpitations
tremor
anxiety
menstrual disturbances
hyperthyroidism signs
tachycardia
lid lag
lid retraction
bilateral exopthalmos
onycholysis - when nail detatches from skin underneith
investigations for hyperthyroidism - primary and secondary results
primary = low TSH, high T3/T4
secondary = high TSH, high T3/T4
thyroid autoantibodies (TPO, thyroglobulin and TSH receptor antibody)
radioactive iodine isotope uptake scan
hyperthyroidism treatment
beta blockers for rapid symptom control during attacks
carbimazole - antithyroid drugs
radioiodine therapy
thyroidectomy
what happens in graves disease
it is autoimmune induced excess production of TH
it is associated with other autoimmune conditions such as T1D and addison’s
there are increased levels of TSH receptor stimulating antibody (TRAb) - this causes excess TH secretion from the thyroid
what are the clinical features of graves disease
it includes all of the clinical features of hyperthyroidism
thyroid achropachy (digital clubbing and finger and toe swelling)
treatment for graves disease
beta blockers
carbimazole
what are the causes of hypothyroidism?
hashimoto’s thyroiditis
iodine deficiency
radiotherapy
over-treatment of hyperthyroidism
hypothyroidism symptoms
fatigue
cold intolerance
weight gain
constipation
menorrhagia
oedema
myalgia
signs of hypothyroidism
BRADYCARDIC
bradycardia
reflexes relax slowly
ataxia
dry thin hair
yawning
cold hands
ascites
round puffy face
defeated demeanour
immobile
congestive heart failure
what is the difference between acromegaly and gigantism
both are increased production of growth hormone but acromegaly is after the fusion of the epiphyseal plates and gigantism is after
what is the incidence of acromegaly
3/m/year
what is the mean age at diagnosis of acromegaly
40
are men or women more affected by acromegaly
M=F
symptoms of acromegaly
acroparaesthesia
sweating
decreased libido
arthralgia
headache
6 signs of acromegaly
massive growth of the hands, feet and jaw
big tongue with widely spaced teeth
puffy lips, eyelids and skin
darkening skin
deep voice
obstructive sleep apnoea
what are the best investigations for acromegaly
- not a random growth hormone test cause these vary throughout the day
- glucose tolerance test
- normally a rise in glucose will suppress GH
- if they’re still high after glucose then this is diagnostic of acromegaly
- follow up with MRI the pituitary fossa to look for adenomas
treatment for acromegaly
transphenoidal surgery to remove the adenoma
give a GH antagonist like pegvisomant
what is the definition of Conn’s syndrome
it refers to high aldosterone independant of the RAAS system which leads to low renin caused by solitary aldosterone producing adenoma
2/3 cases of hyperaldosteronism is conn’s syndrome
1/3 is bilateral adrenocortical hyperplasia
what does excess aldosterone cause
aldosterone works in the kidney to cause potassium loss
therefore excess aldosterone leads to hypokalaemia and sodium and water retention
what are the clinical features of hyperaldosteronism
- they are those of hypokalaemia
- constipation
- weakness and cramps
- parasthaesia
- polyuria and polydipsia
- hypertension due to increased blood flow
investigation for hyperaldosteronism
U&E
decreased renin
increased aldosterone
ECG: flat T wave, long PR interval and Long Qt, U waves
Adrenal CT
in which condition do you have a short 4th metacarpal
Pseudohyperparathyroidism
what is the treatment for hyperaldosteronism
laperoscopic adrenalectomy
spironolactone (potassium sparing diuretic since it is an aldosterone antagonist)
parathyroid hormone is secreted from the parathyroid glands in response to:
a drop in serum calcium levels
what is the action of parathyroid hormone
increased bone resorption by osteoclasts
increased intestinal absorption of calcium
activates calcidiol to calcitriol in the kidney
increased calcium reabsorption and phosphate excretion in the kidney
what are the causes of hyperparathyroidism?
80% are due to a solitary adenoma
20% are due to parathyroid hyperplasia
rarely it’s parathyroid cancer
can also be secondary to hypocalcaemia i.e. that caused by GI diseases/CKD
clinical features of hyperparathyroidism
- those associated with hypercalcaemia:
- weakness
- fatigue
- depression
- polydipsia
- renal calculi
- bone resorption
- pain
- fractures
- osteoporosis
why do you get high calcium PTH in kidney disease
if the kidneys aren’t filtering phosphate into the urine properly then all the free calcium in the blood binds to the phosphate and the PTH thinks there’s hypocalcaemia
the kidneys also aren’t producing enough calcitriol which is responsible for increasing the absorption of calcium in the gut
what is tertiaty hyperparathyroidism
it’s where patients who have had secondary hyperparathyroidism for years develop primary hyper parathyroidism
PTH, Ca and Phosphate levels in primary, secondary and tertiary hyperparathyroidism
primary: high PTH, high Ca and low phosphate (PTH makes kidney excrete phosphate)
secondary: high PTH, low Ca and high phosphate (likely caused by dodgy kidney not filtering phosphate into urine properly)
tertiary: everything’s high as it’s a progression of 2ndary (phosphate will be low if they have a new kidney)
investigations for hyperparathyroidism
bloods for PTH, Ca, and phosphate
dexa scan for osteoporosis
24h urinary calcium excretion
treatment for hyperparathyroidism
fluids
surgically treat underlying cause
bisphosphinates
causes of hypoparathyroidism
autoimmune destruction of PT glands
congenital abnormalities
surgical removal (secondary)
what are the signs and symptoms of hypoparathyroidism
- the same as hypocalcaemia: CATS
- convulsion
- arrhythmias
- tetany
- spasm and stridor
treatment for hypoparathyroidism
calcium supplementation
calcitriol
synthetic PTH
what is pseudohypoparathyroidism
decreased bone response to pth
bloodwork: low ca, high PTH
treat as you would normal hypoparathyroid
what is hypokalaemia
[K+] <3.5mmol/L
low K+ in the blood draws K+ out of cells
this causes hyperpolarisation of the myocycte membrane causing decreased myocyte excitability
what is hypokalaemia Ix
ECG
U have No Pot and No T but a long PR and a long QT
U waves
no T wave
long PR
long QT
treatment for mild and severe hypokalaemia
oral K+
IV K+
hyperkalaemia ECG
tall tented T waves
small P waves
wide QRS
non-urgent treatment of hyperkalaemia
polystyrene sulphonate resin = binds K+ in the gut decreasing uptake
urgent treatment for hyperkalaemia
calcium gluconate (decreases risk of VF)
insulin with dextrose
causes of lowered potassium intake
anorexia
fasting
causes of excess potassium intake
excessive consuption at a fast rate - IV fluids
which hormone stimulates the secretion of K+ in the kidneys?
aldosterone
why might ACEis and ARBs cause hyperkalaemia
they reduce the production of aldosterone which is responsible for the secretuion of K+ into the urine