Osteomalacia Flashcards
What is Osteomalacia
Defective bone mineralistaion after epiphyseal fusion due to VIT D Deficiency
What do you call defective bone mineralisation BEFORE epiphysel fusion
Rickets
Why does Vit D deficiency cause osteomalacia
Increased Calcium uptake by gut and Phosphate (Hydroxyapatite mineral of bone) Less uptake by bone
What are the causes of Osteomalacia
HyperPTH Vit D deficiency CKD/Renal Fail Liver Fail Anticoagulants
Why does hyperPTH cause Osteomalcia
Increase calcium release from bone so less used for mineral formation due to Vit D deficiency
how does Renal fail cause Osteomalacia
Low Vit D activation (LESS 25 Hydroxy Vit D into 1, 25 Hydroxy Vit D)
How does liver fail cause osteomalacia
Low Vit D reaction pathway (LESS Cholecalciferol into 25 Hydoxy Vit D)
How do anticoagulants cause osteomalacia
Increase cyp450 metabolism of Vit D
What is the Vit D pathway
7 Dehydrocholesterol into Cholecalciferol
Cholecalciferol into 25 Hydroxy Vit D (Liver)
25 Hydroxy Vit D INTO 1, 25 Hydroxy Vit D (Kidney)
What is cholecalciferol
Inactive Vit D3
What is 1, 25 Hydroxy Vit D
Activated VIT D3
Where does Activated Vit D3 Travel to
Bone
GIT
Kidney
What are the presentations of Osteomalacia
Fractures
Proximal weakness
Can’t lift heavy
What are the presentations of Rickets
Skeleton deformities
- Knocked knees
- Bowed legs
- Wide Epiphyses
How is Osteomalacia investigated
BM Biopsy (Incompletee mineralisation) Bloods= Hypocalcemia, Riased PTH, Low 25 HydroxyVitD Xray = Looser's Zones
