osteoperosis, osteomalacia + Pagets- 4th Flashcards
what is Pagets disease?
Increased and uncontrolled bone turnover
-excessive osteclast absorption followed by increase ostrablastic activity
-the bone turnover is not coordinated leading to high density (sclerosis) and low density (lysis)
who most commonly gets Pagets?
Most common in >40 years
M>F
Presentation Pagets?
Bone pain
Bone deformity
Fractures
Hearing loss
Bossing of skull
where in the body does Pagets most commonly affect?
AXIAL SKELETON
-skull, spine, thoracic cage, sacrum type of area
bloods of someone with pagets? + explain whyyy
-raised ALP
-normal phosphate
-normal calcium
ALP released from osteoblast activity- increased OB activity so ALP is raised
Calcium + phosphate are not raised as the body compensates
what is seen on Xray - Pagets
-bone enlargement + deformity
-Osteoperosis circunscripta (well defined osteolytic lesions)
-cotton wool appearance of the skull
-V shaped osteolytic defects on long bones
Management of Pagets?
1st line = Biphosphonates
(alendronate / risendronate)
Other:
-calcitonin
-NSAID (for bone pain)
-Calcium + vit D
why are biphosphonates used to treat Pagets?
they inhibit the osteoclast activity
SE of biphosphonates? (alendronate + risendronate)
-Reflux + oesophageal erosions
-Osteonecrosis of jaw and auditory canal
complications of Pagets?
- Hearing loss (bones in ear affected)
- HF
- Osteosarcoma
- Spinal stenosis
Spinal cord compression
what is osteomalacia?
Soft bones resulting from vit D deficiency
-same process in children causes rickets
who is at higher risk of getting osteomalacia?
- Malabsorption disorders (IBS)
- CKD
- Low exposure to sunlight
- Live in colder climates
- Spend time indoors
- Darker skin
Secondary hyperparathyroidism
why is Vit D important for healthy bones?
Vit D is needed for the absorption of calcium + phosphate in the intestines and kidneys
low vit D= low calcium + phosphate
Parathyroid glands are triggered by low calcium levels + release PTH
PTH triggers increased osteclast activity leading to further bone breakdown
presentation of osteomalacia?
May be asymptomatic
* Fatigue * Bone pain * Muscle weakness * Muscle aches * Pathological or abnormal fractures * Bowing deformity
May have a Waddling gate
what would someone with osteomalacias bloods look like?
Low serum- 25 hydroxyvitamin D (lab investigation for vit D)
Low serum calcium
Low serum phosphate
High alkaline phosphatase (osteoblast)
High parathyroid hormone (secondary PTH)
what investigation would be done to check the vitamin D?
serum 25- hydroxyvitamin D
what would an Xray shoe of someone with osteomalacia?
Osteopenia (looks more transluscent)
-Looser zones AKA pseudo fractures (fragility fractures that go partially through the bone)
management of osteomalacia?
Colecalciferol (vit D3)
what is osteoperosis?
significant reduction in bone density
pathophysiology of osteoperosis?
Reduction in bone density due to:
-increased bone breakdown by osteoclasts + decreased bone formation by osteoblasts
who is at higher risk- osteoperosis?
-Increase age
-Post menopausal women lack of eostrogen
-Reduced mobility + activity
-Low BMI (<19)
-Low calcium/ vit D intake increases osteoclast activity
-Alcohol + smoking
-Chronic disease (CKD, hyperthyroidism, RA)
-Long term corticosteroids (e.g. prednisolong >3 months)
what medications increase risk of osteoperosis?
SSRIs
PPIs
Anti epileptics
Anti oestrogens
what medications are protective for osteoperosis?
HRT
Tamoxifen
how is osteoperosis diagnoseD?
DEXA scan
<-2.5
osteoperosis vs severe osteoperosis vs osteopenia on DEXA?
T score <-2.5
Severe osteoporosis= T score <-2.5 plus a fracture
Osteopenia -1 to -2.5
tool used to decide to do a DEXA scan- osteoperosis
10 year of major osteoporotic facture + hip fracture can be calculated:
* Qfracture tool (preferred)
* FRAX tool (may underestimate risk)
Patients >10% are considered for DEXA scan
treatment- osteoperosis?
1st line= bisphosphonates
* Alendronate (oral)
* Risedronate (oral)
* Zoledronic acid (IV once yearly)
(Inhibit osteoclast activity)
