Inclusion Body Myositis

Idiopathic inflammatory myopathy usually occurring in men over 50 years

Aetiology

  • Idiopathic

Clinical presentation

  • Slowly progressive weakness of mainly distal muscles
  • Characteristic thumb sparing
  • Weakness of the pharyngeal muscles causes difficulty in swallowing in over 50%

Investigations

  • CK - only slightly elevated
  • EMG - myopathic and neuropathic changes
  • MRI - changes often more distal but similar to polymyositis
  • Muscle biopsy

Management

  • Prednisolone