What is the treatment for Aspergillus niger infection on an ear swab?

Treatment of Aspergillus Niger Otomycosis

Topical therapy with boric acid or acetic acid irrigation followed by topical antifungal cream is the first-line treatment for Aspergillus niger otomycosis. 1

Initial Management

For uncomplicated Aspergillus niger otomycosis (external ear canal infection):

1. Mechanical cleaning: Thorough cleansing of the external auditory canal to remove fungal debris and cerumen 1
2. Topical therapy: Apply one of the following:
   • Boric acid irrigation
   • Acetic acid irrigation
   • Topical antifungal cream (clotrimazole preferred over tolnaftate) 2

Treatment Algorithm

For intact tympanic membrane:

1. Clean the ear canal thoroughly to remove debris
2. Apply topical therapy:
   • Boric acid or acetic acid irrigation
   • Follow with clotrimazole cream application
3. Continue treatment for 7-14 days
4. Reassess after one week (75% resolution rate with clotrimazole) 2

For perforated tympanic membrane:

1. Clean the ear canal carefully
2. Consider systemic antifungal therapy with:
   • Voriconazole
   • Posaconazole
   • Itraconazole 1

For refractory cases:

1. Consider topical voriconazole 1% solution (3 drops, 3-4 times daily for 14 days) 3
2. For invasive infection (rare), systemic voriconazole with surgical intervention 1

Clinical Considerations

• Aspergillus niger is the most common cause of otomycosis 1, 2
• Common symptoms include pruritus, pain, hypoacusis, and otic discharge 1
• Risk factors include:
  • Immunocompromised status (HIV, diabetes, hypogammaglobulinemia)
  • Chronic eczema
  • Corticosteroid use
  • Previous bacterial otitis media 1

Important Caveats

1. Avoid ototoxic preparations if tympanic membrane perforation is present
2. Monitor for extension beyond the external ear canal, especially in immunocompromised patients
3. Prevent recurrence by addressing underlying conditions and ensuring complete eradication
4. Avoid ear manipulation as it's a common risk factor for otomycosis 2
5. Consider drug monitoring if using systemic triazoles, as bioavailability can vary significantly 4

Evidence Quality

The recommendations for topical therapy are based on moderate-quality evidence 1, while systemic therapy recommendations for refractory or invasive cases are based on lower-quality evidence consisting primarily of case reports and expert opinion 1. Clotrimazole has demonstrated superior efficacy (75% resolution vs. 45% with tolnaftate at one week) in a randomized controlled trial 2.