What is the treatment for Trichophyton rubrum infections?

Treatment of Trichophyton rubrum Infections

Terbinafine is the first-line treatment for Trichophyton rubrum infections, with oral terbinafine 250 mg daily for 1-2 weeks recommended for most cutaneous infections and longer durations for nail infections. 1, 2

Treatment Options Based on Infection Site

Cutaneous Infections (Tinea corporis, Tinea cruris, Tinea pedis)

First-line therapy:

• Topical treatment for localized infections:
  • Terbinafine 1% cream applied once daily for 1-2 weeks 1
  • Clotrimazole 1% cream or Miconazole 2% cream applied twice daily for 2 weeks 1
  • Ciclopirox olamine 0.77% cream/gel applied twice daily for 4 weeks (particularly effective for T. pedis) 3

For extensive or resistant infections:

• Oral therapy:
  • Terbinafine 250 mg once daily for 1-2 weeks 1, 2
  • Itraconazole 100 mg once daily for 15 days (87% mycological cure rate) 3, 1
  • Griseofulvin (dosage based on weight) for cases resistant to other treatments 1, 4

Nail Infections (Tinea unguium/Onychomycosis)

• Oral terbinafine 250 mg daily for 6-12 weeks for fingernails and 12-16 weeks for toenails 2
• Pulse therapy option: Terbinafine 250 mg daily for 7 consecutive days every 3 months (not effective if given every 4 months) 5
• Alternative: Itraconazole 200 mg twice daily for 1 week per month, for 2-3 months (fingernails) or 3-4 months (toenails) 1

Special Considerations

Deep Dermatophytosis

For immunocompromised patients with deep T. rubrum infections:

• Extended oral terbinafine therapy (250 mg daily for up to 6 months) 6
• Close monitoring for progression of infection 7

Prevention of Recurrence

• Apply antifungal powders to shoes and between toes after bathing 3, 1
• Daily changes of socks and thorough drying between toes 3
• Avoid sharing towels and personal items 3, 1
• Periodic cleaning of athletic footwear 3

Monitoring and Treatment Duration

• Continue treatment until at least one week after clinical resolution 1
• For nail infections, treatment should continue until healthy nail growth is visible at the base 2, 5
• Follow-up mycological examination is recommended for resistant or recurrent cases 1

Potential Adverse Effects

• Terbinafine: Generally well-tolerated; may cause gastrointestinal disturbances, rash, headache; rare serious adverse reactions include Stevens-Johnson syndrome and hepatic toxicity (not recommended in patients with active or chronic liver disease) 1, 2
• Itraconazole: Primarily gastrointestinal side effects, cutaneous eruptions, and occasional headache 1
• Griseofulvin: Gastrointestinal disturbances and rashes in <8% of patients; contraindicated in lupus erythematosus, porphyria, and severe liver disease 1, 4

Treatment Algorithm

1. Confirm diagnosis through KOH preparation, fungal culture, or PCR
2. Assess infection extent:
   • Localized cutaneous → Topical therapy
   • Extensive cutaneous or resistant to topical → Oral therapy
   • Nail involvement → Oral therapy (longer duration)
   • Deep infection in immunocompromised → Extended oral therapy with monitoring
3. Monitor response and continue treatment until clinical and mycological cure
4. Implement preventive measures to avoid recurrence

T. rubrum is the most common dermatophyte worldwide, and proper treatment selection based on infection site and severity is essential for successful eradication.