parathyroid Flashcards
calcium absorption physiology + storage
vit D –> liver and kidneys convert to calcitrol –> increase ca absorption in intestines –> stored in bones
how is calcium bound in blood
free calcium // albumin // anions
effect of PTH on the bone
increase osteoclasts –> release Ca + phosphate
PTH on kidney
increase activation of Vit D in proximal tubules // increase Ca reabsorption in distal tubule // increase phosphate excretion
function vit D
increase absorption dietry ca
what is calcitonin
secreted by thyroid // increases Ca reabsorption into bones // (opposes PTH)
what is primary hyperparathyroid
excess PTH –> hypercalcaemia
causes primary hyperparathyroid
85% solitary adenoma // hyperplasia // multiple adenoma // carcinoma
symptoms primary hyperthyroid
hypercalcaemia –> bones stones groans moans // polydipsia, depression, constipation, peptic ulcer, pancreatitis, fractures, renal stones, hypertension
assoc primary hyperparathyroid
hypertension // MEN I + II
invx primary hyperparathyroid
raised Ca, low phosphate // raised PTH (or normal) // MIBI scan // X ray
x ray findings primary hyperparathyroid
pepperpot skull
definitive mx primary hyperparathyroid
parathyroidectomy
indications for parathyroidectamy primary hyperparathyroid
ca >1 // hypercalciuuria // creatinine clearance <30 // kidney sctone // <50 // neuromsuclar // ostoeporosis
conservtive mx primary hyperparathyroid
cinacalcet (increase action of Ca on tissues, reduced PTH) // if unsuitable for surgery
causes secondary hyperparathyroid
chronic renal failure
bloods secondary hyperparathyroid
high PTH // low Ca // high phosphate // low vit D
mx secondary hyperparathyroid
replacement + kidney transplant
bloods tertiary hyperparathyroid
raised PTH // raised Ca // low or normal phosphate + vit D // raised ALP
causes tertiary hyperparathyroid
ongoing hyperplasia from seconadary hyperparathyroid
causes hypoparathyroid
surgery // DiGeorge // autoimmune
bloods hypoparathyroid
decreased PTH // low Ca // raised phosphate
symptoms hypoparathyroid
(hypoca) muscle twitchy, cramp // perioral parasthesia // depression
ECG hypoparathyroid
long QT
trousseuas sign hypoparathyroid
occlude brachial artery –> carpal spasm
chvostek sign hypoparathyroid
tapping parotid –> fascial muscle twitch
what is Pseudohypoparathyroidism + what protein abormality
target cells are not sensitive to PTH // G protein not working
bloods Pseudohypoparathyroidism
high PTH // low Ca // high phosphate
symptoms Pseudohypoparathyroidism
low IQ, short stature, short 4th + 5th metacarpal
diagnosis Pseudohypoparathyroidism
PTH infusion –> urinary cAMP + phosphate –> no change
bloods psuedopseudohypoparathyroidism
symptoms of Pseudohypoparathyroidism but normal bloods
