What is the treatment for furunculosis of the external ear?

Treatment of Furunculosis of the External Ear

The treatment for furunculosis of the external ear includes local heat application, incision and drainage of fluctuant lesions, and systemic antibiotics that cover Staphylococcus aureus, the most common causative agent. 1

Understanding External Ear Furunculosis

Furunculosis of the external ear is the presence of an infected hair follicle on the outer third of the ear canal, sometimes referred to as localized otitis externa. Unlike diffuse acute otitis externa (AOE), which affects the entire ear canal, furunculosis is a focal infection.

Clinical Presentation

• Otalgia (ear pain)
• Otorrhea (ear drainage)
• Localized tenderness
• Focal swelling
• Pustular lesions in the outer ear canal

Treatment Algorithm

First-line Treatment

1. Local heat application

   • Helps to promote localization and drainage of the furuncle
   • Can be applied using warm compresses several times daily

2. Incision and drainage

   • Indicated when the furuncle is fluctuant (has formed a fluid-filled abscess)
   • Should be performed with sterile technique
   • Essential for adequate drainage of purulent material

3. Systemic antibiotics

   • Required to effectively treat the infection 1
   • First-line choice: Antistaphylococcal antibiotics
     • Cephalexin (covers Staphylococcus aureus) 2
     • Typical dosing: 500mg orally four times daily for 7-10 days
   • For suspected MRSA: Consider alternative antibiotics based on local resistance patterns

Adjunctive Measures

• Pain management

  • Assess pain severity and treat accordingly
  • Options include acetaminophen, NSAIDs, or combination with opioids for severe pain 1

• Topical therapy

  • May include mupirocin ointment applied to the affected area three times daily 3
  • Continue until clinical response (typically 3-5 days)

Special Considerations

For Recurrent Furunculosis

If furunculosis recurs, consider:

1. Nasal decolonization with mupirocin ointment 4, 5
2. Chlorhexidine body washes 4
3. Hygiene measures including frequent changing of towels and bedding 4, 5
4. Low-dose prophylactic antibiotics for 3 months in persistent cases 4
5. Screening and treating family members who may be carriers 5, 6

Modifying Factors

Assess for conditions that may complicate management 1:

• Diabetes
• Immunocompromised state
• Prior radiotherapy
• Non-intact tympanic membrane

Common Pitfalls to Avoid

1. Using only topical antibiotics without drainage

   • Inadequate for deep follicular infections; systemic antibiotics are necessary 1

2. Failure to identify and treat S. aureus carriers

   • Nasal carriage of S. aureus occurs in 60% of individuals with recurrent furunculosis 7

3. Inappropriate antibiotic selection

   • Ensure coverage for S. aureus, the predominant pathogen 1
   • Consider local resistance patterns, especially MRSA prevalence 7

4. Inadequate follow-up

   • Patients should be re-evaluated if not showing improvement within 3-5 days 3
   • Persistent or recurrent infections may require culture and susceptibility testing 2

By following this structured approach to treatment, most cases of external ear furunculosis can be effectively managed with good outcomes for pain relief and resolution of infection.