Osteomalacia

Question 1

Definition and presentation of osteomalacia

Answer 1

• Defective bone mineralisation causing ‘soft’ bones
• Resulting from insufficient vitamin D
• Presents with fatigue, bone pain, muscle weakness, muscle aches and pathological or abnormal fractures

NB - Think about the risk factors for vitamin D deficiency in your exams and clinical practice. Patients with osteomalacia are likely to have risk factors such as darker skin, low exposure to sunlight, live in colder climates and spend the majority of their time indoors.

Question 2

Investigation and management of osteomalacia

Answer 2

• Measure serum 25-hydroxyvitamin D
  
  • <25nmol/l - vitamin D deficiency
  • 25-50nmol/l - vitamin D insufficiency
  • 75nmol/l or above - optimal
• Can also check serum calcium (low), serum phosphate (low), serum ALP (can be high), PTH (may be high in secondary hyperparathyroidism), X-rays (more radiolucent) and DEXA scans
• Management is supplementation with vitamin D (colecalciferol)