Flashcards in 1. Metabolic bone disease Deck (17)
What is osteomalacia a dysfunction of?
Recall 3 features of osteomalacia
Bone pain due to softness
What are the 2 most likely causes of osteomalacia
1. Vit D deficiency
2 Phosphate deficiency
Recall the 3 main functions of vit D
In intestine: increase Ca++ and PO4--- absorption
In bone: increase resorption
In kindeys: increase Ca++ resorption and PO4--- excretion
What is the most likely cause of a phosphate deficiency?
Recall the 5 key biochemical features of osteomalacia
Summarise the pathophysiology of Paget's disease
1. Renal failure:
a) impairs ability to excrete phosphate, leading to hyperphosphataemia
b) leads to 1-alpha-OHase failure so Vit D left inactivated, leading to hypocalcaemia
2. Raised serum ALP --> increased bone turnover
In what population is Paget's most common?
Describe the genetic component of Paget's
Recall the stages of Paget's disease
3. Quiescent osteosclerotic
Recall 3 unobvious clinical features of Paget's
Risk to medulla from skull changes
Recall the 2 chief causes of primary hyperPTHism and their relative influence
Parathyroid adenoma (85%-95%)
Chief cell hyperplasia (5%-15%)
Where is bone biopsy usually performed?
Recall 4 indications for bone biopsy
X ray abnormality
Recall the 2 methods of performing a bone biopsy
Closed: use Jamshidi needle
Open: under general anaesthetic
What would indicate an open bone biopsy?
Slerotic/ inaccessible lesions