Endo- parathyroid disorders Flashcards
what is hyperparathyroidism
overactivity of the parathyroid glands with high levels of parathyroid hormone (PTH)
what is primary hyperparathyroidism
caused by uncontrolled parathyroid hormone produced directly by a tumour of the parathyroid glands
hypercalcaemia symptoms
fatigue
depression
bone pain
myalgia
nausea
thirst
polyuria
renal stones
osteoporosis
hyperparathyroidism blood results
increased calcium
increased ALP
increased PTH
hypercalcaemia way of remembering symptoms
STONES , BONES, GROANS, PHSYIC MOANS
eg gallstones, bone pain, ab pain
common complication of parathyroidetomy
hypocalcaemia
most common cause of primary hyperparathyroidism
parathyroid adenoma
causes of secondary hyperparathyroidism
vitamin D deficiency
chronic renal failure
- causes hypocalcaemia
what does PTH do to bones
activates osteoclasts- increased bone reabsorption- releases calcium
what genetic syndromes commonly involve early parathyroid adenomas
MEN1
MEN2
what is the mode of inheritance of familial hypocalciuric hypercalcaemia
autosomal dominant
drugs that cause hypercalcaemia
vitamin D
thiazides
lithium
what enzyme level may be raised in hypercalcaemia of malignancy
serum alkaline phosphatase (ALP)
causes of hypocalcaemia
chronic kidney disease
congenital absence (DiGeorge syndrome)
destruction (surgery, radiotherapy, malignancy)
autoimmune
hypomagnesaemia
idiopathic
pseudohypoparathyroidism
clinical features of hypocalcaemia
paresthesia- fingers, toes, perioral
muscle cramps, tetany
muscle weakness
fatigue
bronchospasm/laryngospasm
fits
what is chovesteks sign
gentle tapping over the facial nerve causes twitching of the ipsilateral facial muscles
what is trousseau sign
inflation of the sphygmomanometer cuff above systolic pressure for 3 min induces tetanic spasm of the fingers and wrist
ECG findings in hypocalcaemia
QT prolongation
causes of hypomagnesemia
alcohol
drugs- thiazides, PPIs
GI illness with diarrhoea
pancreatitis
malabsorption
clinical features of hypomagnesemia
anorexia
nausea and vomiting
muscle weakness, lethargy
fits
what is pseudohypoparathyroidism
condition associated primarily with resistance to the parathyroid hormone
which genetic defect occurs in pseudohypoparathyroidism
GNAS1 gene- affects Gs alpha subunit
what type of inheritance is seen in pseudohypoparathyroidism
typically autosomal dominant with variable expression
clinical features of pseudohypoparathyroidism
bone abnormalities
obesity
subcutaneous calcification
learning disability
brachdactyly (shortened 4th metacarpal)
bloods in psuedohypoparathyroidism
low calcium
elevated PTH
