Parathyroid

Question 1

What does parathyroid hormone do?

Answer 1

Raised serum Ca

Released immediately in response to low intracellular Ca

Question 2

Vitamin D

Answer 2

Steroid hormone
Activation steps are regulated (also self regulated)
Binding transport protein in the blood
Binds to a cellular receptor
Increases absorption of Ca from gut and reabsorption by kidney, thereby to promote bone formation
Lots of functions

Question 3

2 functions of PTH on the kidney

Answer 3

Increases Ca reabsorption

Decreases phosphate reabsorption

Question 4

Features of hypercalcemia

Answer 4

Stones
Bones (osteoporosis)
Abdominal moans
Psychic overtones (makes you feel awful)
Ultimately coma and death

Question 5

What is an important manifestation in hyperparathyroidism?

Answer 5

Stones

Question 6

Features of hypocalcemia

Answer 6

Tetany (hyperexictability of the entire NS)
Lethargy and depression
Dry skin, coarse hair, brittle nails
Arrhythmia
Late stages: heart failure, steatorrhea

Question 7

What cells in the parathyroid glands secrete PTH?

Answer 7

Chief cells

Question 8

CsR

Answer 8

Calcium sensing receptor

Immediate controller of PTH secretion and synthesis

Question 9

If you see hypercalcemia, the diagnosis is almost always…

Answer 9

Primary hyperparathyroidism

Be careful in renal failure, and exclude familial hypocalcuric hypercalcemia

Question 10

Who is primary hyperparathyroidism most common in?

Answer 10

Women over 40

Question 11

In primary hyperparathyroidism would you see high/low/normal PTH?

Answer 11

High

Question 12

If you have renal insufficiency, what would you see for

1. PO
2. Ca
3. 1 alpha hydroxylation
4. PTH

Answer 12

1. High
2. Low
3. Low
4. High