Malignant Otitis Externa
- Also termed necrotizing otitis externa or skull base osteomyelitis
- Invasive infection of the external auditory canal and skull base
- Gender: Male < Female
- Age: Common in elderly (>60 years)
- Diabetes mellitus is the most important risk factor
- Causative organism: Pseudomonas aeruginosa (95%)
Four Cardinal Features of Necrotizing OE:
- Otalgia >1 month
- Otorrhea/Granulation tissue
- Advanced age, Diabetes, or Immune suppression
- Cranial neuropathy
Three Cranial Nerves Most Often Involved:
- Facial (75%)
- Vagus (70%)
- Accessory (56%)
Workup:
Labs:
- ESR
- CRP
- Blood sugar
- Culture and Sensitivity
- Biopsy
Imaging:
- CT scan
- MRI
- Technetium-99 bone scan (Osteoblastic)
- Gallium scan (Leukocytes)
Management:
- Aural toilet
- Analgesia
- Antibiotics (Long term)
- Control of diabetes
- ID consultation
- Surgery
Antibiotics:
- Systemic + Local
- Duration: 6-8 weeks
- Examples: Ciprofloxacin, Levofloxacin, Piperacillin, Piperacillin-tazobactam, Ceftazidime, Cefepime
