Flashcards in 1. Metabolic bone disease Deck (17)
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1
What is osteomalacia a dysfunction of?
Mineralisation
2
Recall 3 features of osteomalacia
Bone pain due to softness
Proximal weakness
Bone deformity
3
What are the 2 most likely causes of osteomalacia
1. Vit D deficiency
2 Phosphate deficiency
4
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
5
What is the most likely cause of a phosphate deficiency?
CKD
6
Recall the 5 key biochemical features of osteomalacia
Hypocalcaemia
Hypophosphataemia
High ALP
Low calcitriol
Secondary hyperPTHism
7
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
8
In what population is Paget's most common?
Caucasians >40
9
Describe the genetic component of Paget's
Autosomal
Incomplete penetrance
10
Recall the stages of Paget's disease
1. Osteolytic
2. Osteolytic-osteosclerotic
3. Quiescent osteosclerotic
11
Recall 3 unobvious clinical features of Paget's
Deafness
Nerve compression
Risk to medulla from skull changes
12
Recall the 2 chief causes of primary hyperPTHism and their relative influence
Parathyroid adenoma (85%-95%)
Chief cell hyperplasia (5%-15%)
13
Where is bone biopsy usually performed?
ASIS
14
Recall 4 indications for bone biopsy
Investigation of:
Unexplained infection
X ray abnormality
Bone tumour
Therapy efficacy
15
Recall the 2 methods of performing a bone biopsy
Closed: use Jamshidi needle
Open: under general anaesthetic
16
What would indicate an open bone biopsy?
Slerotic/ inaccessible lesions
17
