Malignant otitis externa

Background

• Life-threatening infection of external ear/canal, soft tissue, +/- spread to skull base
• Diabetes and immunosuppression are main risk factors
• Pseudomonas causes >90% of cases
• Begins as simple otitis externa

Clinical Features

Adults

• Otitis externa that has not resolved despite 2-3wks of topical antibiotics
• Otalgia
  • Often out of proportion for routine otitis externa
• Edema of external auditory canal
• Granulation tissue often seen in the ear canal floor
• CN IX, X, or XI involvement
• Trismus

Pediatrics

• More rapidly progressive than in adults
  • Fever, leukocytosis, bacteremia/sepsis
• TM, middle ear, and facial nerve more likely to be affected

Differential Diagnosis

Ear Diagnoses

External

• Auricular hematoma
• Auricular perichondritis
• Cholesteatoma
• Contact dermatitis
• Ear foreign body
• Herpes zoster oticus (Ramsay Hunt syndrome)
• Malignant otitis externa
• Otitis externa
• Otomycosis
• Tympanic membrane rupture
  • Otic barotrauma

Internal

• Acute otitis media
  • Bullous myringitis
• Chronic otitis media
• Mastoiditis

Inner/vestibular

• Labyrinthitis, vestibular neuritis
• Meniere's disease
• Sudden sensorineural hearing loss

Diagnosis

• CT

Treatment

Adults

• Antipseudomonal cephalosporin OR fluoroquinolone

Peds

• Imipenem OR (aminoglycoside + antipseudomonal penicillin)

Disposition

• Contact ENT for disposition decision; early infection may be managed as outpt

Complications

1. Lateral or sigmoid sinus thrombosis
2. Meningitis

See Also

• Otitis Externa
• Otitis Media (Peds)

Source

• Tintinalli