How to treat Tinea capitis that is progressing to impetigo?

Treatment of Tinea Capitis Progressing to Impetigo

For tinea capitis that is progressing to impetigo, a combination of oral antifungal therapy for the fungal infection plus appropriate antibacterial treatment for the bacterial superinfection is required. 1

Diagnostic Approach

• Confirm both infections before initiating treatment:
  • For tinea capitis: Collect scalp scrapings, hair pluck, brush samples or swabs for microscopy and culture 1
  • For impetigo: Take swabs from pustular lesions for bacterial culture
• Microscopy using 10-30% potassium hydroxide can provide rapid preliminary diagnosis of fungal elements 1
• Culture on Sabouraud agar is necessary to identify the specific dermatophyte species 1

Treatment Algorithm

Step 1: Initiate Oral Antifungal Therapy

• Griseofulvin remains the only licensed treatment for tinea capitis in children in many countries 1, 2
  • Dosage: 20-25 mg/kg/day for 6-8 weeks 1, 2
  • Take with fatty food to improve absorption 1
• Alternative oral antifungals if griseofulvin is unavailable or ineffective:
  • Terbinafine: Weight-based dosing for 4 weeks (preferred for Trichophyton species) 1, 3
  • Itraconazole or fluconazole may be considered in treatment failures 4, 5

Step 2: Add Antibacterial Treatment for Impetigo

• Topical antibiotics for localized impetigo
• Oral antibiotics for extensive impetigo or when topical treatment fails
• Common choices include flucloxacillin, cephalexin, or clindamycin depending on local resistance patterns

Step 3: Add Adjunctive Topical Therapy

• Antifungal shampoo to reduce spore transmission:
  • Options include selenium sulfide 1%, ketoconazole 2%, or povidone-iodine shampoos 1, 5
  • Use 2-3 times weekly throughout oral treatment course 1
• Topical antibacterial washes or cleansers for impetigo component

Special Considerations

For Inflammatory Tinea Capitis (Kerion)

• If severe inflammation is present, short-term oral corticosteroids may be considered alongside antifungal therapy 4
• Kerion is commonly seen with zoophilic species but can occur with endothrix infections like T. tonsurans 1

For Treatment Failures

• Ensure adequate duration of therapy - treatment must continue until the infecting organism is completely eradicated 2
• Consider changing antifungal agent if no improvement after 2-4 weeks 1
• Verify compliance with medication regimen
• Re-evaluate diagnosis if no response to appropriate therapy 1

Follow-up and Monitoring

• Monitor for mycological cure, not just clinical improvement 1
• Repeat mycology sampling at the end of standard treatment period 1
• Continue treatment until mycological clearance is documented 1
• Screen family members for asymptomatic carriage, particularly for anthropophilic infections like T. tonsurans 1

Prevention of Recurrence and Transmission

• Cleanse combs, brushes, and other fomites with disinfectant 1
• Use antifungal shampoo for household contacts to prevent spread 1
• Avoid sharing of personal items like combs, hats, and pillowcases 1

Remember that topical antifungal therapy alone is not recommended for tinea capitis as it does not penetrate the hair follicle adequately 1, 5. Systemic therapy is essential for eradication of the fungal infection 1.