What is the recommended antibiotic (abx) treatment for perichondritis?

Antibiotic Treatment for Perichondritis

For auricular perichondritis, fluoroquinolone antibiotics (ciprofloxacin or levofloxacin) are the first-line treatment due to their excellent coverage against Pseudomonas aeruginosa and Staphylococcus aureus, the most common causative pathogens. 1

Pathogen Considerations

Perichondritis is an infection of the cartilage and surrounding tissue that most commonly affects the ear (auricular perichondritis). The causative organisms typically include:

• Abscess-forming perichondritis: Predominantly Pseudomonas aeruginosa (58-69% of cases) 2, 3
• Non-abscess perichondritis: Predominantly Staphylococcus aureus (49% of cases) 2

First-Line Treatment Options

Outpatient Treatment (Mild-Moderate Cases)

• Fluoroquinolones: Ciprofloxacin 500-750mg orally twice daily or levofloxacin 750mg orally daily for 7-10 days 1, 4
  • Excellent coverage for both P. aeruginosa and S. aureus
  • Demonstrated efficacy in outpatient treatment of P. aeruginosa auricular perichondritis 4

Inpatient Treatment (Severe Cases)

• Fluoroquinolones: Ciprofloxacin 400mg IV every 12 hours or levofloxacin 750mg IV daily 1
• Alternative options (based on severity and local resistance patterns):
  • Clindamycin (for S. aureus coverage) 1
  • Ceftazidime (for P. aeruginosa coverage) 1
  • Cefepime (for broader coverage) 1

Treatment Algorithm

1. Assess severity:

   • Mild-moderate: Localized erythema, tenderness, minimal swelling
   • Severe: Extensive swelling, systemic symptoms, abscess formation

2. Initial antibiotic selection:

   • Mild-moderate cases: Oral fluoroquinolone (ciprofloxacin or levofloxacin)
   • Severe cases: IV fluoroquinolone or combination therapy

3. If abscess is present:

   • Surgical incision and drainage is necessary in addition to antibiotics 5
   • Expand coverage to ensure P. aeruginosa is targeted 2, 3

4. Reassess after 72 hours:

   • If improving: Complete 7-10 day course
   • If worsening or no improvement: Consider surgical intervention and culture-directed therapy

Special Considerations

• Early treatment is critical: Delayed treatment can lead to cartilage necrosis and permanent auricular deformity 5, 6
• Surgical intervention: Required in approximately 7-31% of cases, particularly when abscess is present 3, 6
• Duration of therapy: Typically 7-10 days for uncomplicated cases, may need to be extended in severe cases or poor response

Common Pitfalls

1. Failure to cover P. aeruginosa: This is the predominant pathogen in abscess-forming perichondritis and requires specific antibiotic coverage 3

2. Delayed surgical intervention: When abscess is present, antibiotics alone are often insufficient and drainage is necessary 5, 6

3. Inadequate duration of therapy: Premature discontinuation can lead to treatment failure and progression to cartilage necrosis

4. Misdiagnosis as simple cellulitis: Perichondritis specifically involves the cartilage and requires targeted therapy against the typical causative organisms

By following this approach with early, appropriate antibiotic therapy targeting the most likely pathogens, the risk of permanent auricular deformity can be significantly reduced.