Biochemistry Flashcards
what is osteoporosis
quantitative defect of bone characterised by reduced bone mineral density and increased porosity
WHO definition of osteoporosis
bone mineral density less than 2.5 standard deviations below mean peak value of young adults of same race and sex
osteopenia
bone mineral density 1-2.5 standard deviations below mean peak value
type 1 osteoporosis
post-menopausal with an exacerbated loss of bone
type 2 osteoporosis
old age with greater decline in bone mineral density than expected
diagnosis of osteoporosis
DEXA bone scan
calcium and phosphate in osteoporosis
both normal
aim of treatment in osteoporosis
slow down further deterioration and hopefully decrease the risk of subsequent fracture
drugs for osteoporosis
calcium and vit D
bisphosphonates
desunomab
strontium
what do bisphosphonates do
reduce osteoclastic resorption
what does desunomab do
monoclonal antibody reducing osteoclast activity
what is osteomalacia
qualitative defect of bone with abnormal softening of the bone due to deficient mineralisation of osteoid secondary to inadequate amounts of calcium and phosphorus
what is rickets
the same disease as osteomalacia but occurring in children
bone biochem in osteomalacia/rickets
low calcium
low phosphate
high alkaline phosphatase
pathophysiology of Pagets disease
increased osteoclast activity results in increased bone turnover
osteoblasts become more active to try to correct excessive bone resorption
new bone fails to remodel sufficiently so resulting bone is brittle and can fracture easily
