Metabolic bone disease

Question 1

Osteoclasts and progenitor cell

Answer 1

bone resorption

myeloid

Question 2

osteoblasts and progenitor cell

Answer 2

bone formation

mesenchymal

Question 3

Pagets disease

Answer 3

increased bone resorption followed by increased bone formation

Question 4

Describe how pagetic bone compares to normal bone

Answer 4

bigger, less compact, more vascular and more susceptible to fracture and deformity

Question 5

what % of pagets is familial?

Answer 5

strong genetic component: 15-30%

Question 6

Environmental and geographical - Paget’s

Answer 6

anglo-saxan

chronic viral infection in osteoclast

Question 7

Symptoms of Paget’s disease

Answer 7

over 40's
bone pain 
bone deformity? 
excessive heat over bone 
neurological complications eg nerve deafness

Question 8

Most common presentation of Paget’s in 21st century

Answer 8

isolated elevation of serum alkaline phosphatase

Question 9

presentation of pagets

Answer 9

bone pain and local heat
hearing loss
bone deformity or fracture
rarely osteosarcoma

Question 10

Treatment of Paget’s

Answer 10

IV bisphosphonates - one off zoledronic acid infusion

Question 11

Cause of rickets/osteomalacia

Answer 11

vit D or calcium deficiency leading to insufficient mineralisation

Question 12

difference between osteomalacia and rickets

Answer 12

rickets in a growing child and osteomalacia when the growth plates have fused

Question 13

What does vit D do for calcium and phosphate?

Answer 13

stimulates absorption from the gut

Question 14

symptoms of osteomalacia

Answer 14

bone pain, muscle weakness and increased falls risk

Question 15

Osteogenesis imperfecta

Answer 15

genetic disorder of connective tissue meaning the bones are fragile

Question 16

Connective tissue affected in osteogenesis imperfecta

Answer 16

type 1 collagen

Question 17

how many types of Osteogenesis imperfecta are there and which types are most common?

Answer 17

8

first 4

Question 18

Type 1 Osteogenesis imperfecta

Answer 18

milder - when child starts to walk, can present in adults

Question 19

Type 2 Osteogenesis imperfecta

Answer 19

lethal by age 1

Question 20

type 3 Osteogenesis imperfecta

Answer 20

progressive deforming with severe bone dysplasia and poor growth

Question 21

type 4 Osteogenesis imperfecta

Answer 21

similar to type 1 but more severe

Question 22

Other features of Osteogenesis imperfecta

Answer 22

growth deficiency - hearing loss - defective tooth formation - blue sclera - ligamentous laxity - scoliosis - easy bruising

Question 23

The brighton score is for what?

Answer 23

Osteogenesis imperfecta

Question 24

describe the brighton score

Answer 24

1 point for each thumb touching wrist, each finger more than 90 degrees, each elbow more than 10 degrees, each knee more than 10 degrees and touch floor with straight legs

Question 25

4 management principles of Osteogenesis imperfecta

Answer 25

surgery - treat fractures medical - IV bisphosphonates social - education and adaptions genetic counselling

Question 26

Osteoporosis

Answer 26

low bone mass, microarchitectural degeneration and increased bone fragility and fracture risk

Question 27

FRAX

Answer 27

fracture risk assessment - age, BMD, falls etc

Question 28

What does DXA stand for?

Answer 28

dual energy x-ray absorptiometry

Question 29

Endocrine causes of osteoporosis

Answer 29

``` thyrotoxicosis hypo/hyper parathyroidism hypopituitarism low sex levels cushings hyperprolactinaemia ```

Question 30

rheumatic causes of osteoporosis

Answer 30

RA, ankylosing spondylitis, polymyalgia rheumatica

Question 31

GI causes of osteoporosis

Answer 31

inflammatory - UC and crohn's liver disease - PBC, cirrhosis, Hep C malabsorption - coeliac, CF, ischaemic bowel

Question 32

6 medications which cause osteoporosis

Answer 32

``` PPI steroids GnRH inhibitors aromatase inhibitors warfarin enzyme inducing anti-epileptics ```

Question 33

peak BMD

Answer 33

about 30

Question 34

When does BMD start to decrease rapidly?

Answer 34

menopause

Question 35

How do we prevent osteoporotic fractures?

Answer 35

minimise risk factors ensure good calcium and vitamin D falls prevention strategies medications

Question 36

Side effects of HRT

Answer 36

blood clots, breast cancer and heart disease and stroke

Question 37

Example of selective oestrogen receptor modulator

Answer 37

raloxifene

Question 38

Side effects of selective oestrogen receptor modulator

Answer 38

hot flushes, clotting risk and lack of hip protection

Question 39

1st line for osteoporosis

Answer 39

oral bisphosphonates

Question 40

What are the requirements of the individual for oral bisphosphonates in osteoporosis?

Answer 40

renal function, vit D and calcium - adequate | good dental hygiene

Question 41

SE of oral bisphosphonates

Answer 41

oesophagitis - iritis/uveitis - eGFR <30ml/min - atypical femoral shaft fractures

Question 42

Denosumab

Answer 42

monoclonal ab against RANKL

Question 43

How does denosumab work?

Answer 43

osteoclast formation function and survival inhibited | reduce osteoclatic bone resorption

Question 44

How is denosumab administered?

Answer 44

subcut injection every 6 months

Question 45

Side effects of denosumab

Answer 45

allergy/rash, symptomatic hypocalcaemia if vit D deplete,? ONJ, atypical femoral shaft fractures

Question 46

What is teriparatide?

Answer 46

intermittent human parathyroid hormone

Question 47

Disadvantages of teriparatide

Answer 47

injection site irritation - allergy - ? hypercalcaemia - cost