Primary Hyperparathyroidism

Question 1

What characterizes hyperparathyroidism?

Answer 1

Abnormally high parathyroid hormone (PTH) levels in the blood.

Question 2

What are the three types of hyperparathyroidism?

Answer 2

Primary, secondary, and tertiary.

Question 3

What causes primary hyperparathyroidism?

Answer 3

Overactivity of the parathyroid glands, most commonly due to an adenoma.

Question 4

What causes secondary hyperparathyroidism?

Answer 4

Chronic kidney disease or vitamin D deficiency.

Question 5

What is tertiary hyperparathyroidism a result of?

Answer 5

Prolonged secondary hyperparathyroidism leading to autonomous gland function.

Question 6

Where is PTH produced?

Answer 6

In the parathyroid glands located behind the thyroid.

Question 7

What stimulates PTH production?

Answer 7

Low blood calcium and high phosphate levels.

Question 8

What is PTH’s main goal?

Answer 8

Increase blood calcium and decrease blood phosphate.

Question 9

What cells in bone does PTH activate?

Answer 9

Osteoclasts, to release calcium and phosphate into the blood.

Question 10

How does PTH affect the kidneys?

Answer 10

Increases calcium reabsorption and decreases phosphate reabsorption.

Question 11

What enzyme does PTH activate in the kidneys?

Answer 11

1-alpha hydroxylase.

Question 12

What does 1-alpha hydroxylase do?

Answer 12

Converts calcidiol to calcitriol, the active form of vitamin D.

Question 13

What is the active form of vitamin D?

Answer 13

1,25-dihydroxycholecalciferol (calcitriol).

Question 14

What does active vitamin D do in the gut?

Answer 14

Increases absorption of calcium and phosphate.

Question 15

What type of feedback does vitamin D have on PTH?

Answer 15

Negative feedback to suppress PTH secretion.

Question 16

Most common cause of primary hyperparathyroidism?

Answer 16

Parathyroid adenoma.

Question 17

What syndrome is associated with primary hyperparathyroidism?

Answer 17

MEN syndromes (Type 1 and Type 2).

Question 18

Lab findings in primary hyperparathyroidism?

Answer 18

High PTH, hypercalcemia, hypophosphatemia, hypercalciuria.

Question 19

First-line treatment for primary hyperparathyroidism?

Answer 19

Parathyroidectomy.

Question 20

What are calcimimetics?

Answer 20

Drugs that mimic calcium to reduce PTH secretion.

Question 21

How does chronic kidney disease cause secondary hyperparathyroidism?

Answer 21

By causing phosphate retention and reducing vitamin D synthesis.

Question 22

What are common lab findings in secondary hyperparathyroidism?

Answer 22

High PTH, normal/low calcium, high phosphate.

Question 23

Treatments for secondary hyperparathyroidism?

Answer 23

Treat CKD, low phosphate diet, phosphate binders, ergocalciferol.

Question 24

What do phosphate binders like sevelamer do?

Answer 24

Bind phosphate in the gut to reduce absorption.

Question 25

What happens in tertiary hyperparathyroidism?

Answer 25

Parathyroid glands become autonomous and secrete PTH regardless of calcium or phosphate levels.

Question 26

What are the lab findings in tertiary hyperparathyroidism?

Answer 26

Very high PTH, hypercalcemia, hyperphosphatemia.

Question 27

What is the treatment for tertiary hyperparathyroidism?

Answer 27

Parathyroidectomy or calcimimetics.

Question 28

What dietary deficiency can lead to secondary hyperparathyroidism?

Answer 28

Vitamin D deficiency.

Question 29

What hormone is elevated in all types of hyperparathyroidism?

Answer 29

Parathyroid hormone (PTH).

Question 30

What is the main clinical consequence of untreated hyperparathyroidism?

Answer 30

Persistent hypercalcemia, bone disease, and renal complications.