Invasive infection of the bone surrounding the ear canal (i.e. the mastoid and temporal bones)

Aetiology

• Relatively rare complication of otitis externa
• Pseudomonas aeruginosa is the most common cause
• Risk factors - diabetes, and radiotherapy to the head and neck

Clinical features

Symptoms

• Pain and headache, more severe than clinical signs would suggest

Signs

• Granulation tissue at bone-cartilage junction of ear canal
• Exposed bone in the ear canal
• Facial nerve palsy

Investigations

• Bloods: inflammatory markers
• Imaging
• Biopsy and culture: to demonstrate extent of the osteitis and its cause

Management

• Fatal without treatment - osteomyelitis will progressively involve the skull and meninges
• Treatment includes:
  • Correction of immunosuppression (when possible)
  • Local treatment of the auditory canal (e.g. cleaning and debridement, topical antibiotics)
  • Long-term systemic antibiotic therapy
  • Surgery in selected patients