Otitis externa

Background

Microbiology

  • Staph/Strep
  • Pseudomonas
  • Enterobacter
  • Proteus
  • Fungus
    • Aspergillus, candida (may present after abx tx)

Risk Factors

  • Swimming
  • Excessive Q-tip use

Diagnosis

  • Rapid onset (generally within 48 hours) in the past 3 weeks, AND.[1]
  • Symptoms of ear canal inflammation, which include:
    • otalgia (often severe)
    • itching, or fullness, WITH OR WITHOUT
    • hearing loss or jaw pain AND...
  • Signs of ear canal inflammation, which include:
    • tenderness of the tragus, pinna, or both OR
    • diffuse ear canal edema, erythema, or both WITH OR WITHOUT
    • otorrhea
    • regional lymphadenitis
    • tympanic membrane erythema, or
    • cellulitis of the pinna and adjacent skin

Differential Diagnosis

  • Malignant Otitis Externa
  • Otomycosis
    • Pts complain more of itching than pain
    • Characteristic appearance on exam; like mold growing on spoiled food
    • Treatment
      • Cleaning of ear canal
      • Topical antifungal
  • Contact Dermatitis
    • Chronic suppurative otitis media
    • Ear canal findings are usually mild compared with bacterial external otitis
  • Ramsay Hunt syndrome

Treatment

  • Clean the ear canal
    • Cerumen wire loop or cotton swab
    • 1:1 dilution of 3% hydrogen peroxide if TM is visible and intact
  • Analgesia
    • NSAIDs
  • Avoiding promoting factors
    • Keep ear canal dry
    • Abstain from water sports for 7-10 days

Antibiotics

  1. Ofloxacin (Floxin otic): 5 drops in affected ear BID x 7 days[1]
    • Safe with perforations
  2. Ciprofloxacin-hydrocortisone (Cipro HC): 3 drops in affected ear BID x 7 days
    • Contains hydrocortisone to promote faster healing
    • Not recommended for perforation since non-sterile preparation
  3. Ciprofloxacin-dexamthasone (Ciprodex): 4 drops in affected ear BID x 7 days
    • Similar to Cipro HC but safe for perforations
    • Often more expensive
  4. Cortisporin otic (neomycin/polymixin B/hydrocortisone): 4 drops in ear TID-QID x 7days
    • Use suspension (NOT solution) if possibility of perforation
    • Animal studies suggest possible toxicity from the neomycin although rigorous data is lacking[2]

Disposition

  • F/u in 1-2wks for pts with moderate disease

See Also

Source

  1. 1.0 1.1 Clinical Practice Guideline: Acute Otitis Externa Executive Summary. Otolaryngology -- Head and Neck Surgery 2014 150: 161 DOI: 10.1177/0194599813517659 PDF
  2. Wright, C. et al. Ototoxicity of neomycin and polymyxin B following middle ear application in the chinchilla and baboon. Am J Otol. 1987 Nov;8(6):495-9.