Mastoiditis

Background

Cross sectional ear anatomy (left).

• Inflammation of middle ear spreads into mastoid air cells via the "aditus ad antrum"
• Vast majority of acute mastoiditis occurs as a result of, or simultaneous with, acute otitis media
  • Mastoiditis is unlikely if middle ear examination is normal

Etiology

• S. pneumo (22%)
• S. pyogenes (16%)
• S. aureus (7%)
• H. flu
• P. aeruginosa

Mastoiditis with subperiostal abscess

Clinical Features

• Abnormal TM findings
• Abnormal mastoid findings
  • Erythema, edema, tenderness
• Abnormal pinna findings
  • Protrusion of auricle, obliteration of postauricular crease
• Cranial nerve VI and VII palsies

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

Evaluation

CT scan: Otitis media (single arrow) and mastoiditis (double arrow) of the right side (left side in image). The external auditory canal is partially occupied by suppuration (triple arrow).

• Middle ear fluid cultures
• CT mastoid with IV contrast
  • 90% sensitive
  • Delineates extent of bony involvement
  • Helps to diagnosis abscess formation

Management

• ENT consultation - cases refractory to parenteral antibiotics may require surgical irrigation and debridement with possible mastoidectomy.

Coverage against S. pneumoniae, S. pyogenes, S. aureus, H. influenzae

• Clindamycin 600mg IV q8 hours OR (if MRSA concern use Vancomycin regimen)
• Vancomycin 15-20mg/kg IV q12 hours PLUS
  • Ceftriaxone 1g (50mg/kg) IV once daily OR
  • Ampicillin/Sulbactam 3g (50mg/kg) IV q6 hours
• If chronic or severe, need pseudomonas coverage
  • Vancomycin + Piperacillin/Tazobactam 100mg/kg/dose piperacillin IV q6h (max 4g piperacillin/dose)

Pediatric

• Ceftriaxone 50mg/kg IV daily (max 2g) OR
• Ampicillin/Sulbactam 50mg/kg IV q6hrs (max 3g/dose)
• If MRSA concern: add Vancomycin 15mg/kg IV q6hrs
• If chronic/severe: Piperacillin/Tazobactam 100mg/kg IV q6hrs (max 4.5g/dose) + Vancomycin
• Clindamycin 10-13mg/kg IV q8hrs (max 900mg/dose) as alternative

Disposition

• Admit

Complications

Include, but are not limited to:

• Meningitis
• Encephalitis
• Venous sinus thrombosis
• Brain abscess
• Facial nerve palsy
• Sepsis

See Also

• Otitis Media
• Bezold abscess