8: Pathology of the Parathyroid - Fang Flashcards
most common cause of primary hyperparathyroidism
parathyroid gland adenoma
characterized by lesions within the gland that secrete excessive PTH
could also be autonomous overproduction of PTH not suppressed by negative feedback from calcium
excessive PTH –>
hypercalcemia
observe - hypercalciuria, flank pain and hematuria ,
“stones, bones, groans and moans”
primary hyperparathyroidism
kidney stones and bone changes
mental changes and hypercalcemia leading to increased gastrin and ulcers
brown tumors =
osteitis fibrosa cystica
hypercalcemia leads to _____ before anything else
muscle weakness and fatigue
people who eventually turn out to hae primary hyperparathyroidism are much more likely to have been missing a lot of work
how do you find the 10% of parathyroid adenomas that are ectopic?
Tc99 sestamibi nuclear imaging –> iminimally invasic radioguided parathyroidectomy
what does a parathyroid adenoma look like clincally?
no fat and primarily chief cells
all four glands are big for no obvious reason
parathyroid hyperplasia
second most important cause of primary hyperparathyroidism
suspicious for multiple endocrine neoplasia syndrome
rim v. no rim of normal parathyroid tissue
an adenoma has a rim of normal tissue, no rim for hyperplasia
most often cause of secondary hyperparathyroidism
chronic renal failure causing secondary hypersecretion of PTH
thick fibrous bands =
parathyroid carcinoma
also see mitotic activity and capsular invasion
3 causes of hypoparathyroidism
- automimmune
- sugical mistake
- digeorge syndrome
what is digeorge syndrome?
failure of descent of 3rd and 4th branchial pouches resulting in parathyroid agenesis
diagnosis for hypoparathyroidism
decreased serum calciium and increased serum phosphate
treat with vit D and calcium cookies
