Vitamin D deficiency Flashcards
1
Q
Definition
A
Deficiency: serum 25OH Vit D <20
Insufficiency: 20-29
2
Q
physiology
A
- increases GI absorption and renal excretion of Ca
- PTH production
- contributes to normal bone growth and mineralization
3
Q
complications
A
-2ndary hyperparathyroidism and inadequate bone mineralization
4
Q
metabolism
A
-dieatry intake of Vit D2(ergocalciferol) from plants
dietary intake of Vit D3 (cholecalciferol) from animals
-sunlight activates, converted to 25OH Vit D by liver
-converted to 1,25OH active by kidney
5
Q
risk factors
A
- elderly (decreased skin production)
- northern climates, dark skin
- GI disease (IBD), bariatric surgery
- medications (phenytoin, steroids, rifampin, cholestyramine)
6
Q
screening
A
-all patients at risk
7
Q
labs
A
- 25OH Vit D
- PTH
- in renal patients test 1,25OH vit D as well, because they may have decreased final conversion in kidney and still be insufficient
8
Q
treatment
A
Deficiency:
-ergocalciferol 50,000 IU weekly for 8-12 weeks and repeat level after
Insuffiency
-800 to 2000 IU qd will replete levels by 3 months
