Hyperparathyroidism

Question 1

What are the three predominant cell types in the parathyroid glands?

Answer 1

Chief cells, oxyphil cells and adipocytes

Question 2

2 histo features of chief cells she wants us to know?

Answer 2

Light pink or white cytoplasm with secretory granules containing parathyroid hormone

Question 3

2 histo features of oxyphil cells?

Answer 3

Darker and tons of mitochondria

Question 4

What is one big change to the parathyroid gland with increasing age?

Answer 4

gets more fatty

Question 5

What is the trigger to release parathyroid hormone and what are the 4 functions of PTH?

Answer 5

Drop in free blood calcium. 
Increases renal calcium absorption
Increase conversion of vitamin d to its active form
Increases urinary phosphate excretion
Increases intestinal calcium absorption

Question 6

What are the three classifications of hyperparathyroidism?

Answer 6

Primary: hyperplasia of parathyroid tissue or an adenoma in the gland itself producing too much PTH
Secondary: compensatory hyper secretion of PTH because of chronic hypocalcemia. Usually due to chronic renal failure
Tertiary: Persistent hyper secretion of PTH. Renal transplant.

Question 7

3 top causes of primary hyper?

Answer 7

Adenoma, hyperplasia, carcinoma

Question 8

Age and gender of patients most commonly presenting with primary hyper?

Answer 8

50s and women

Question 9

What is the most common cause of primary hyper?

Answer 9

Adenoma arising sporadically

Question 10

What is the most common mutation associated with sporadic parathyroid adenomas?

Answer 10

somatic MEN 1

Question 11

2 histo features of a parathyroid adenoma?

Answer 11

Almost always solitary and a rim of normal parathyroid tissue surrounds it

Question 12

Primary hyperplasia of the parathyroid gland may occur in what 2 ways? What is the classic histo feature of it?

Answer 12

Sporadically or part of MEN syndrome.

Chief cell hyperplasia.

Question 13

What are we thinking if there are tumors on all 4 glands?

Answer 13

Hyperplasia

Question 14

What is the only reliable criteria for diagnosing parathyroid carcinoma?

Answer 14

Metastasis and invasion of surrounding tissue.

Question 15

What are the symptoms of hyperparathyroidism?

Answer 15

Bones, groans, moans, and stones.
Essentially, anything that occurs because of too much calcium.
Constipation, weakness, fatigue.

Question 16

What is the most common cause of asymptomatic hypercalcemia and what is the most common cause of symptomatic hypercalcemia?

Answer 16

Primary hyper.

Malignancy

Question 17

What is osteitis fibrosis cystica?

Answer 17

Primary hyper causes 3 bad things to happen in bone: brown tumors, osteoporosis and osteitis. So basically decreased bone mass because you are talking away bone, and the increase in osteoclast activity is so great that it essentially destroys the bones.

Question 18

How do we define secondary hyper?

Answer 18

Any condition that leads to chronic hypocalcemia so we are constantly triggering PTH release.

Question 19

What is by far the most common cause of secondary hyper And tertiary hyper?

Answer 19

Renal failure

Question 20

What is the main difference between the histo of primary and secondary hyperplasia of the para gland?

Answer 20

Primary is usually asymmetrical.

Secondary is hyper-plastic and symmetrical.

Question 21

What is the most common mechanism by which osteolytic tumors induce hypercalcemia?

Answer 21

The tumors secrete PTH related peptide which induce osteoclast activity.

Question 22

What is the sign on radiograph of hyperparathyroidism and what does it mean?

Answer 22

Rugged jersey sign.
Essentially there is this striping pattern down the vertebral column because there is loss of bone mass from increased osteoclast activity.

Question 23

What is the term for the skeletal abnormalities form too much PTH?

Answer 23

Renal osteodystrophy

Question 24

Explain calciphylaxis and its main problems?

Answer 24

Tons and tons of calcium and cause occlusion and calcification of blood vessels causing ischemic damage to skin and other organs blocked off from blood flow.

Question 25

Explain the concept of hypercalcemia because of malignancy?

Answer 25

Squamous carcinomas producing PTHrp that does the same thing as PTH.
Lymphomas producing tons of Vitamin D which leads to lots of calcium.
Ectopic hyperparathyroidism which is rare.
Cancers causing Osteolysis, so directly cause calcium release.

Question 26

Top 2 carcinomas causing PTHrp release?

Answer 26

Breast and lung

Question 27

Top 3 cancers causing calcium release via osteolysis?

Answer 27

Breast, lung and myeloma

Question 28

Why is it so important to calcium homeostasis to excrete phosphate?

Answer 28

Because it binds to free calcium in the blood and takes out our normal functioning calcium.