thyroid and parathyroid

Question 1

what stimulates the parathyroid glands to release PTH

Answer 1

low serum calcium

Question 2

what form of calcium is sensed?

Answer 2

ionized calcium

Question 3

where does the increase in calcium come from?

Answer 3

the bone, intestine, and kidney

Question 4

how does the kidney respond to PTH?

Answer 4

it increases its secretion of phosphate, retains calcium, produces 1, 25 hydroxyvit D, which stimulates the intestinal absorption.

Question 5

how does VIt D increase calcium?

Answer 5

stimulates intestinal absorption and stimulates osteoclasts.

Question 6

how is vit D regulated?

Answer 6

tightly, through the action of calcium, PTH and phosphorus

Question 7

what are the most common causes of hypercalcemia?

Answer 7

hyperparathyroidism and malignancy

Question 8

what is the first step in diagnosing hyperthyroidism

Answer 8

PTH levels! always first

Question 9

PTH levels in primary hyperparathyroid?

Answer 9

high or normal

Question 10

primary hyperparathyroidism characteristics and statistics ?

Answer 10

3:1 women, more common when 60. typically caused by hyper secretion in one or more glands. solitary adenoma 80% of the time. less common that all glands are hypertrophied.

Question 11

how is primary hyperPT diagnosed on labs?

Answer 11

elevated calcium, elevated or normal PTH, low phosphorus, elevated urine calcium.

Question 12

secondary hyperPT characteristics

Answer 12

perceived low calcium concentration. can occur in renal disease due to phosphate retention and lack of 1-alpha hydroxylase activity in the kidney thus a deficiency of activated Vit D.

Question 13

how does high phosphorus effect the PTH system?

Answer 13

it will stimulate PTH secretion

Question 14

what do you have to prescribe sometimes in renal disease, due to phosphorus and why?

Answer 14

low phosphate diet, phosphate binders, replacement of activated Vit D and dialysis.

Question 15

can vitamin D deficiency cause hyperPT

Answer 15

yes. very common actually. need to replace sometimes.

Question 16

tertiary hyperPTism characteristics and causes

Answer 16

PT becomes autonomous after prolonged hyperPTism. this is similar to primary, in that the gland is hyper secreting. this is different from secondary in the sense that the calcium in high, not low.

Question 17

hypocalcemia characteristics

Answer 17

the PTH levels will be high in effort to counteract. can be caused by destruction of the parathyroid, or failure to produce. characterized by the level of PTH

Question 18

hypoPTism

Answer 18

PTH produced is insufficient to meet demands or is unable to function properly. usually there is a low serum calcium and low PTH.

Question 19

pseudohypoPTism

Answer 19

similar to hypo but the PTH is elevated. there is a resistant state.

Question 20

thyroid disease characteristics and demographics

Answer 20

most prevalent endocrine disorder. usually a slow and insidious process, often vague symptoms not understood by the patient. often misdiagnosed.

Question 21

hypothyroid

Answer 21

failure to secrete adequate amounts of hormone.

Question 22

primary hypothyroid

Answer 22

destruction of the thyroid or interference with hormone synthesis.

Question 23

secondary hypothyroid

Answer 23

hypothalamic or pituitary disease.

Question 24

labs for primary hypothyroidism

Answer 24

high TSH, low T4

Question 25

labs for secondary hypothyroid

Answer 25

T4 low but TSH low or normal.

Question 26

common causes of primary hypothyroidism

Answer 26

hashimotos. idiopathic (usually old hash), irradiation of the thyroid, surgical removal, fibrous thyroiditis, iodine deficiency, drug therapy, infiltrative diseases

Question 27

causes of secondary hypothyroid

Answer 27

pituitary or hypothalamic tumor, congenital hypopituitarism, pituitary necrosis

Question 28

hypothyroid face?

Answer 28

apathetic facies, lack of eyebrows, bilateral ptosis.

Question 29

risk factors for hypothyroid

Answer 29

age (men > 60, women >35), sex (female), goiter, history of thyroid dysfunction, family history, head/neck/thyroid surgery, autoimmune disease, drug, hypercholesterolemia

Question 30

treatment for hypothyroid

Answer 30

levothyroxine aiming to normalize TSH.

Question 31

hyperthyroidism

Answer 31

hyper metabolic state caused by increased availability of hormone.

Question 32

clinical features of hyperthyroid

Answer 32

nervousness, irritability, sweating, goiter, rapid HR, bulging eyes, warm moist palms, infertility, weight loss, first-trimester miscarriage. difficulty sleeping.

Question 33

causes of hyperthyroidism

Answer 33

diffuse toxic goiter (graves), diffuse multinodular goiter, toxic adenoma.

Question 34

Graves

Answer 34

autoimmune disorder, favors women 8:1, thyroid stimulating antibodies to the TSH receptor causes hypertrophy and hyper secretion.

Question 35

ophthalmic disorder graves

Answer 35

true infiltrative eye disease, results in periorbital edema, conjunctival swelling and congestion, limited upward and lateral gaze, keratitis.

Question 36

acute/subacute thyroiditis

Answer 36

viral or bacterial etiology

Question 37

De Quervains subacute thyroiditis

Answer 37

lymphocytic (painless, subacute), post-partum thyroiditis,

Question 38

labs for primary hyperthyroid

Answer 38

suppressed TSH levels, high T4 and T3. increased radioactive iodine uptake.

Question 39

which forms of iodine are used to image the thyroid?

Answer 39

I123, I131.