What is the next best step in managing a jock itch rash expanding into the buttocks with improved itching on day 7 of pulse dose itraconazole (itraconazole) after failing OTC creams, oral terbinafine (terbinafine), and oral fluconazole (fluconazole)?

Management of Resistant Jock Itch Extending to Buttocks

Complete the current course of pulse dose itraconazole and add a topical antifungal cream to the affected areas, including the buttocks, for at least 2-4 weeks after all lesions have resolved.

Assessment of Current Situation

The patient presents with:

• Jock itch rash extending into buttocks
• Daily noticeable enlargement despite treatment
• Improved itching symptoms
• Currently on day 7 of pulse dose itraconazole
• Previous treatment failures:
  • OTC antifungal creams
  • 14-day course of oral terbinafine
  • 10-day course of oral fluconazole

Treatment Approach

1. Complete Current Therapy

• Continue the current pulse dose itraconazole regimen to completion
• Itraconazole is effective against both dermatophytes and Candida species, making it appropriate for resistant fungal infections 1
• Pulse therapy with itraconazole (typically 200mg twice daily for 1 week per month) has shown clinical response rates of 90% and mycological cure rates of 76-77% for dermatomycoses 2

2. Add Adjunctive Topical Therapy

• Add a prescription-strength topical antifungal to use concurrently:
  • Ciclopirox 8% cream applied twice daily
  • OR Econazole 1% cream applied twice daily
  • Apply to all affected areas including the buttocks and surrounding skin

3. Extend Treatment Duration

• Continue treatment for 2-4 weeks after all visible lesions have resolved 1
• For resistant infections, treatment duration may need to be longer than standard courses

Rationale for This Approach

1. Superiority of itraconazole for resistant infections:

   • Itraconazole has demonstrated efficacy against fungal infections that have failed other treatments 1
   • For Candida infections (which may be present in resistant cases), itraconazole shows significantly greater efficacy than terbinafine 1

2. Benefit of combination therapy:

   • Adding topical therapy to systemic treatment addresses both the systemic spread and provides direct local antifungal action
   • This dual approach is particularly important when the infection is expanding despite systemic therapy

3. Importance of adequate treatment duration:

   • The British Association of Dermatologists guidelines recommend continuing treatment for 2-4 weeks after clinical resolution to ensure mycological cure 1

Monitoring and Follow-up

• Evaluate the response after completing the current pulse of itraconazole
• If improvement is noted but complete resolution has not occurred, consider:
  • An additional pulse of itraconazole (200mg twice daily for 1 week) 2
  • Extending the topical treatment duration

Common Pitfalls to Avoid

1. Premature discontinuation:

   • Stopping treatment when symptoms improve but before complete resolution often leads to recurrence
   • Continue treatment for 2-4 weeks after visible clearing of the rash

2. Inadequate application area:

   • Apply topical treatments beyond the visible borders of the rash (approximately 2cm)
   • Include all potentially affected areas, including skin folds and adjacent regions

3. Overlooking contributing factors:

   • Ensure the patient:
     • Wears loose-fitting, breathable cotton underwear
     • Thoroughly dries the affected areas after bathing
     • Changes clothes, particularly underwear, daily
     • Avoids sharing towels or personal items

4. Misdiagnosis:

   • If no improvement occurs after completing the recommended treatment, consider:
     • Skin biopsy to confirm diagnosis
     • Fungal culture with susceptibility testing
     • Alternative diagnoses such as psoriasis, seborrheic dermatitis, or contact dermatitis

If the infection continues to spread or fails to improve after completing the current pulse of itraconazole plus topical therapy, referral to a dermatologist for further evaluation and possibly different systemic therapy options would be warranted.