CKD

Question 1

How does CKD leaad to Vit D Deficiency?

Answer 1

Decreased ability to convert 25-OH to 1,25-OH2

Question 2

How does CKD lead to inc phos?

Answer 2

Decreased ability of the kidneys to excrete phos.

Question 3

How does CKD lead to hyperPTH?

Answer 3

• Vit D def from inability to convert
• HypoCa from dec Vit D and thus dec intestinal Ca abs
• hyperPhos from dec excretion

–> inc PTH

Question 4

Phosphate binders

Answer 4

Calcium Carbonate (Tums) - increases serum calcium

Calciun acetate (Phos-Lo)- increases serum calcium

Sevelamer (Renvela) - possible mortality benefit over Ca based, possible lipid-lowering effects, dec Vit D/E/K and folate abs

Question 5

Benefit of ACE-I/ARBs in CKD

Answer 5

slows progression of CKD and MICROalbuminuria, but still benefit for pts with MACROalbuminuria

Question 6

indication for vasopressin antagonists

Answer 6

hypervolemic hyponatremia

tolvaptan and conivaptan

Question 7

contraindication for vasopressin antagonists

Answer 7

• severe cerebral symptoms (too slow to provide benefit); use hypertonic saline instead
• hypovolemic hyponatremia (need volume resus to halt ADH release)
• advanced CKD (ineffective)

vasopressin antagonists = conivaptan and tolvaptan;