Paget's disease of the bone

Question 1

what is it?

Answer 1

disease of bone turnover

disorder of osteoclasts - excessive osteoclastic resprotipn followed by osteoblastic activity

Question 2

risk factors

Answer 2

increasing age
male sex
northern latitude
family history

Question 3

clinical features

Answer 3

older male with bone pain and isolated raised ALP

bone pain - pelvis, lumbar spine and femur

bowing of tibia, bossing of skull

Question 4

Ix

Answer 4

1. bloods - raised ALP
2. other markers of bone turnover
3. xrays
4. bone scintigraphy

Question 5

what happens to calcium and phosphate

Answer 5

normal levels

Question 6

what are the other markers of bone turnover

Answer 6

procollagen type I N-terminal propeptide (PINP)
serum C-telopeptide (CTx)
urinary N-telopeptide (NTx)
urinary hydroxyproline

Question 7

what is seen in X-rays

Answer 7

osteolysis in early disease → mixed lytic/sclerotic lesions later

skull x-ray: thickened vault, osteoporosis circumscripta

Question 8

what is bone scintigraphy

Answer 8

a specialized radiology procedure used to examine the various bones of the skeleton.

It is done to identify areas of physical and chemical changes in bone. A bone scan may also be used to follow the progress of treatment of certain conditions.

Question 9

what is seen in bone scintigraphy?

Answer 9

sites of active bone lesions

Question 10

Mx

Answer 10

bisphosphonates - PO risendronate or IV zolendraonate

Question 11

indications for tx

Answer 11

bone pain
skull or long bone deformity
fracture
periarticular Paget’s

Question 12

Complications

Answer 12

deafness (cranial nerve entrapment)
bone sarcoma (1% if affected for > 10 years)
fractures
skull thickening
high-output cardiac failure