Treatment of CKD-related Hyperparathyroidism

Question 1

What do oral phosphate binders do?

Answer 1

Lower plasma phosphate levels

In CKD phosphate elimination is dec. so phosphate is elevated

Question 2

How does the high phosphate levels related to CKD lead to hyperparathyroidism?

Answer 2

Elevated phosphate levels lead to a decrease in plasma Ca++ levels that can lead to hyperparathyroidism

Question 3

Why is the oral phosphate binder Aluminum hydroxide rarely used?

Answer 3

It can causes aluminum toxicity

Question 4

How do the oral phosphate binders calcium carbonate and calcium acetate work and which one is more effective?

Answer 4

Binds to dietary phosphate inhibiting absorption

Calcium acetate is most effective

Question 5

When should calcium carbonate and calcium acetate be dosed?

Answer 5

With meals

Question 6

AE of calcium carbonate and calcium acetate:

Answer 6

Iatrogenic hypercalcemia and increased risk of vascular calcifications
Monitor Ca levels regularly

(Useful in patients with hypocalcemia)

Question 7

When is the risk of hypercalcemia while taking calcium carbonate and calcium acetate increased?

Answer 7

When taking vit D

Question 8

What is the advantage of using the oral phosphate binder Sevelamer (Renagel, Renvela):

Answer 8

Binds dietary phosphate inhibiting absorption and contains no aluminum or calcium

Question 9

Why is Sevelamer carbonate (Revela) used over Sevelamer HCl (Renagel)?

Answer 9

Renvela is the buffered for the drug and does not causes metabolic acidosis like Renagel can

Question 10

Which type of patients might Sevelamer (Renagel, Renvela) be good for?

Answer 10

Patients with hypercalcemia

May also decreased cholesterol absorption by binding bile acids

Question 11

What is Lanthanum carbonate (Fosrenal)

Answer 11

Oral phosphate binder derived from rare earth metal
Contains neither aluminum or calcium
Useful in patients with hypercalcemia

Question 12

_______ vit D synthesis can lead to hyperparathyroidism

Answer 12

Impaired

Question 13

How dose administration of active vit D affect PTH levels?

Answer 13

Lower PTH levels

Question 14

CKD can decrease the activation of vit D, therefore agents that are administered must:

Answer 14

bypass the need for activation in the kidney

Question 15

Calcitrol, Paricalcitrol, and doxecalciferol are examples of:

Answer 15

Vit D (calcitrol) and vit D analogues

Question 16

Where is Doxecalciferol activated to vit D?

Answer 16

Liver

Question 17

Calcimimetics such as Cinacalcet (Sensipar) MOA:

Answer 17

Binds to Ca sensing rc
Increases sensitivity to Ca
Rc’s are activated at lower Ca levels which suppresses PTH synthesis and secretion

Question 18

Calcimimetics are used to treat what in addition to CKD related hyperparathyroidism?

Answer 18

Hypercalcemia associated with parathyroid carcinoma

Question 19

When is IV calcium used and what kinds?

Answer 19

Severe hypocalcemia

Gluconate and chloride

Question 20

Oral Calcium used to treat hypoparathyroidism and osteoporosis include:

Answer 20

Calcium citrate:most absorbed form
Calcium carbonate: low cost, antacid, absorption better with food and in acidic environment (dec absorption with H2 antag and PPIs)

Question 21

AE of Calcium administration:

Answer 21

Constipation, kidney stones

Question 22

Why are cholecalciferol (vit D3-sun) and ergocalciferol (vit D2-diet) ineffective in CKD?

Answer 22

Both forms still need to be converted to their active form

Question 23

What are cholecalciferol (vit D3-sun) and ergocalciferol (vit D2-diet) used to treat?

Answer 23

Hypoparathyroidism
Rickets
Osteomalacia
Osteoporosis

Question 24

In treatment and prevention of osteoporosis with vit D what else is used?

Answer 24

Calcium to increase calcium absorption