Pathology of the Parathyroid

Question 1

normal weight of parathyroid

Answer 1

25-50mg each

there are 4 of them

Question 2

color of parathyroid

Answer 2

yellowish

has fat

more fat with age

Question 3

cells of parathyroid

Answer 3

chief cells

oxyphil cells - more red - more mito

Question 4

function of PTH

Answer 4

increase renal tubular reabsorption of calcium

increase conversion of vit D

urinary phosphate excretion

GI calcium absorption

Question 5

primary hyperparathyroidism

Answer 5

adenoma or hyperplasia of parathyroid tissue

Question 6

secondary hyperparathyroidism

Answer 6

chronic renal failure

compensatory hypersecretion of PTH in response to prolonged hypocalcemia

Question 7

tertiary hyperparathyroidism

Answer 7

renal transplant

persistant hypersecretion of PTH even after cause of prolonged hypocalcemia is corrected

Question 8

most common cause of primary hyperparathyroidism

Answer 8

adenoma - 85%

primary hyperplasia - diffuse or nodular 5-10%

parathyroid carcinoma 1%

Question 9

52yo F elevated Ca on medical profile

sestamibi scan shows hot nodule

Answer 9

parathyroid adenoma

Question 10

calcitonin scan

Answer 10

sestamibi

-technetium scan

Question 11

primary hyperplasia vs. adenoma

Answer 11

adenoma - glands outside adenoma are shrunken - feedback inhibiion

Question 12

most common identification of primary hyperparathyroidism

Answer 12

incidental on serum electrolyte panel - see hypercalcemia

Question 13

genetic parathyroid adenomas

Answer 13

MEN 1 - MEN1 mutation

MEN 2 - RET mutation

Question 14

primary hyperparathyroidism physiologic changes

Answer 14

skeletal system - osteoporosis, brown tumors, osteitis fibrosa cystica

urinary tract - nephrolithiasis

Question 15

skeletal changes hyperparathyroidism

Answer 15

osteoporosis - phalanges, vertebra, femur - cortical bone affected most

medullary bone - osteoclast tunnel - railroad track appearance - dissecting osteitis

Question 16

railroad track appearance

Answer 16

of bones

hyperparathyroidism

dissecting osteitis

Question 17

brown tumor

Answer 17

bone loss in hyperparathyroidism - microfractures - influx of macrophages and fibrous tissue

hemosiderin deposition

Question 18

von recklinghausen disease of bone

Answer 18

osteitis fibrosa cystica

combo of increased osteoclast activity, peritrabecular fibrosis, cystic brown tumors

severe hyperparathyroidism**

Question 19

urinary tract and hyperparathyroidism

Answer 19

urinary tract stone formation - nephrolithiasis

also calcification of renal interstitium and tubules

Question 20

most common cause of asymptomatic hypercalcemia

Answer 20

primary hyperparathyroidism

Question 21

most frequent cause of symptomatic hypercalcemia in adults

Answer 21

malignancy

multiple myeloma

secretion of PTH-rP
-PTH related peptide

Question 22

high calcium and low PTH

Answer 22

high calcium of malignancy

multiple myeloma and others

Question 23

primary hyperparathyroidism associations

Answer 23

painful bones
renal stones
abdominal groans
psychic moans

Question 24

enlargement of all 4 parathyroid glands

Answer 24

secondary hyperparathyroidism
-hyperplasia

most commonly - with renal failure

Question 25

patients with secondary hyperparathyroidism

Answer 25

dietary vit D supps | phosphate binders

Question 26

tx tertiary hyperparathyroidism

Answer 26

minority of patients - becomes excessive hyperparathyroid parathyroidectomy to control hyperparathyroidism

Question 27

common cause of hypoparathyroidism

Answer 27

consequence of surgery during thyroidectomy

Question 28

autoimmune hypoparathyroid

Answer 28

mutations in AIRE childhood onset of candidiasis several years later hypoparathyroidism adolescence adrenal insufficiency

Question 29

auto-dom hypoparathyroidism

Answer 29

GOF in SACR gene hypocalcemia and hypercalciuria

Question 30

familial isolated hypoparathyroidism

Answer 30

FIH - rare auto dom - mutation in PTH precursor peptide auto rec - LOF function in GCM2 - essential for parathyroid development

Question 31

congenital absence of parathyroid

Answer 31

with other malformations thymic aplasia cardiovascular defects 22q11 deletion syndrome

Question 32

chvostek sign

Answer 32

tapping facial nerve - induce contraction of muscles of eye, mouth, nose hypocalcemia**

Question 33

trousseau sign

Answer 33

carpal spasms - with occlusion of forearm circulation hypocalcemia

Question 34

hypocalcemia

Answer 34

tetany - neuromuscular irritability deceased serum calcium levels

Question 35

clinical of hypoparathyroidism

Answer 35

mental status changes intracranial manifestations - parkinsonian like movement disorders ocular disease - lens and cataracts - calcification cardiovascular manifestations - prolonged QT interval dental abnormalities

Question 36

pseudohypoparathyroidism

Answer 36

end organ resistance to PTH action hypocalcemia, hyperphosphatemia, elevated circulating PTH short stature, mental retardation, short 4th and 5th fingers