Osteogenesis Imperfecta

Question 1

what is osteogenesis imperfecta also known as?

Answer 1

brittle bone disease

Question 2

what is osteogenesis imperfecta?

Answer 2

group of disorders of collagen metabolism resulting in bone fragility and fractures

Question 3

what is the most common and milder form of osteogenesis imperfecta

Answer 3

type 1 - abnormality in type 1 collagen due to decreased synthesis of pro-a1 or pro-a2 collagen polypeptides

Question 4

inheritance pattern of osteogenesis imperfecta?

Answer 4

autosomal dominant

Question 5

features of osteogenesis imperfecta?

Answer 5

present in childhood
fractures after minor trauma
blue sclera
deafness secondary to otosclerosis
dental imperfections

Question 6

ix of osteogenesis imperfecta?

Answer 6

adjusted ca, po4, pth, alp usually normal

Question 7

what does this suggest?
high adjusted calcium
high PTH
normal/raised ALP
low PO4

Answer 7

primary hyperparathyroidism

Question 8

what does this suggest?
Low adjusted calcium, low PTH, normal ALP, high PO4

Answer 8

hypoparathyroidism

Question 9

what does this suggest?
Low adjusted calcium, high PTH, normal ALP, low PO4

Answer 9

secondary hyperparathyroidism

nb. po4 levels are variable here

Question 10

what does this suggest?
Raised adjusted calcium, low PTH, raised ALP and raised PO4

Answer 10

malignant pth related protein

can occur in some cancers, incl SCC
alp can be normal here