What is the treatment for severe tinea?

Treatment of Severe Tinea

For severe tinea infections, oral antifungal therapy is required, with the specific agent determined by the causative dermatophyte species: terbinafine for Trichophyton species and griseofulvin for Microsporum species. 1

Diagnosis and Initial Assessment

• Obtain proper samples via scalpel scraping, hair pluck, brush or swab for microscopy and culture
• In severe cases with kerion, scale, lymphadenopathy, or alopecia, treatment can begin while awaiting confirmatory mycology 1
• Topical therapy alone is insufficient for severe tinea infections

First-Line Treatment Options

For Trichophyton species (T. tonsurans, T. violaceum, T. soudanense):

• Terbinafine (preferred for Trichophyton) 1
  • < 20 kg: 62.5 mg daily for 2-4 weeks
  • 20-40 kg: 125 mg daily for 2-4 weeks

  • 40 kg: 250 mg daily for 2-4 weeks

  • Advantages: Shorter treatment course (better compliance), fungicidal action
  • Note: More effective against Trichophyton species than Microsporum species

For Microsporum species (M. canis, M. audouinii):

• Griseofulvin (preferred for Microsporum) 1, 2
  • < 50 kg: 15-20 mg/kg/day (single or divided dose) for 6-8 weeks

  • 50 kg: 1 g/day (single or divided dose) for 6-8 weeks

  • Advantages: Licensed for use in children, extensive clinical experience
  • Disadvantages: Longer treatment duration, gastrointestinal side effects in <8% of patients

Second-Line Treatment

• Itraconazole 1
  • 50-100 mg/day for 4 weeks, or 5 mg/kg/day for 2-4 weeks
  • Effective against both Trichophyton and Microsporum species
  • Consider when first-line therapy fails or is contraindicated
  • Advantages: Available in liquid form, shorter treatment protocols
  • Disadvantages: Not licensed in some countries for children ≤12 years with tinea capitis

Treatment Failure Management

If treatment fails, consider:

1. Lack of compliance
2. Suboptimal drug absorption
3. Relative insensitivity of the organism
4. Reinfection

For cases with clinical improvement but ongoing positive mycology:

• Continue current therapy for additional 2-4 weeks

For cases with no clinical improvement:

• Switch to second-line therapy as outlined above

Alternative Agents for Refractory Cases

• Fluconazole 1

  • Has shown efficacy against T. violaceum, T. verrucosum, and M. canis
  • Once-weekly dosing regimens are well-tolerated
  • Consider for children who cannot tolerate other medications

• Voriconazole 1

  • More potent against dermatophytes than griseofulvin or fluconazole
  • Limited by cost and licensing restrictions
  • Reserve for exceptional cases

Additional Measures

• Children receiving appropriate therapy should be allowed to attend school or nursery 1
• For T. tonsurans infections, screen all family members and close contacts and treat positive cases 1
• Treat asymptomatic carriers with high spore load 1
• Continue treatment until mycological clearance is achieved, not just clinical improvement 1

Important Considerations

• Ketoconazole is no longer recommended due to risk of hepatotoxicity 1
• Topical antifungal agents may be used as adjunctive therapy but are insufficient as monotherapy for severe tinea 1, 3
• The endpoint of treatment should be mycological cure, not just clinical improvement 1
• Monitoring for liver enzyme elevations is generally unnecessary if therapy is limited to ≤4 weeks 4

Remember that proper diagnosis of the infecting organism is essential for selecting the most appropriate treatment, as different antifungal agents have varying efficacy against different dermatophyte species.