(!) Osteomalacia

Question 1

Define Osteomalacia

Answer 1

Metabolic disease characterised by incomplete mineralisation of bones following base closure in adults
(in contrast to rickets, which has incomplete mineralisation of the epiphyseal growth plates)

Most common cause is Vitamin D deficiency

Question 2

Aetiology and risk factors of Osteomalacia

Answer 2

The most common cause is by far Vitamin D deficiency, often related to inappropriate sun exposure, inappropriate dietary supplementation and/or inappropriate absoption
Coeliac, GI surgery, CKD can all contribute
Osteopenia follows from HPTH following low serum calcium. Osteoclast are over active, and increased phosphate is lost in urine

Risk factors:
Age-older
Vitamind D defiicency
CKD, limited sunlight, coeliac
Prior GI surgery
Fanconi syndrome

Question 3

Epidiemology of Osteomalacia

Answer 3

In US/EU, 40% of adults are vitamin D deficient-main cause of Osteomalacia

In developing countries, rickets can be present in nearly 60%

Incidence has gone down

Question 4

Signs and Sx of Osteomalacia

Answer 4

Tends to be asymptomatic in early disease-suspricion from risk factors (sunscreen, coeliac, surgery, poor sunlight, bad diet)

early signs often include -malaise and fatigue
Diffuse bone pain and tenderness
Difficulty rising from sitting positions and changes in gait

Examination is often normal

Frequent fractures can also be a hint

Question 5

Investigations of Osteomalacia

Answer 5

PTH-raised (secondary HPTH)
Calcium-low or normal
Phosphate-Low
Serum Vitamin D -low
serum ALP-raised
24h urine calcium-low

trays-less dense centre of bones
Looserpseudofractures (perpendicular to bone, with area of thickening around), reabsorption of ends of bones

Question 6

Management of Osteomalacia

Answer 6

Treat underlying cause and correct imbalances

give calcium and vitamin D supplementations-dramatic improvements
Vit D metabolites can also be used

CKD-give calcitriol (more active)

Question 7

Complications of Osteomalacia

Answer 7

Insufficiency fractures/looser pseudofractures
Secondary HPTH

Hypercalceamia after replacement

Question 8

Prognosis of Osteomalacia

Answer 8

Dependent on the cause, but if its just dietary etc-replacement is pretty much all thats needed and it works great