What is the treatment for a fungal infection involving the perionyxium (nail fold)?

Treatment for Fungal Infection of the Nail Fold (Perionychium)

For fungal infections involving the nail fold (perionychium), topical antifungal therapy is the first-line treatment, with amorolfine 5% nail lacquer or ciclopirox 8% nail lacquer being the most effective options. 1

Diagnosis Considerations

Before initiating treatment, it's important to identify the causative organism:

• Candida paronychia is the most common fungal infection of the nail fold
• Symptoms include swollen, erythematous, and painful periungual skin
• A gap often develops between the nail fold and nail plate
• Nail plate involvement typically starts proximally with white, green, or black marks
• Unlike dermatophyte infections, pressure on the nail is painful 1

Treatment Algorithm

First-line Treatment:

1. Topical antifungal therapy:

   • Amorolfine 5% nail lacquer: Apply once or twice weekly for 6-12 months
   • Ciclopirox 8% nail lacquer: Apply once daily for up to 48 weeks 1, 2
   • Remove as much diseased nail as possible by gentle filing before application

2. Adjunctive measures:

   • Keep nails short
   • Avoid sharing nail clippers
   • Disinfect footwear
   • Apply antifungal powders inside shoes 3

For Candida Paronychia (most common in nail fold infections):

1. Topical therapy as above
2. If unresponsive to topical therapy, consider:
   • Itraconazole: Particularly effective for Candida infections with 92% cure rate using pulse therapy (400 mg daily for 1 week per month) 3
   • Fluconazole: 150-450 mg once weekly for 3 months (fingernails) or 6 months (toenails) 3, 4

For Severe or Resistant Cases:

1. Terbinafine: 250 mg daily for 6 weeks (fingernails) or 12 weeks (toenails)

   • Most effective for dermatophyte infections with 80-90% cure rates for fingernails and 70-80% for toenails 3
   • Fungicidal action provides better outcomes than fungistatic agents 5

2. Itraconazole: Alternative when terbinafine is contraindicated

   • 200 mg daily for 12 weeks (continuous therapy) or
   • 400 mg daily for 1 week per month (pulse therapy) 3

Special Considerations

• Monitoring: For oral antifungals, baseline liver function tests and complete blood count are recommended, particularly in patients with history of hepatotoxicity 3

• Treatment duration: Follow-up is recommended for at least 48 weeks from treatment initiation, with re-evaluation 3-6 months after starting treatment 3

• Bacterial superinfection: Common in Candida paronychia and may require additional antimicrobial treatment 1

• Treatment failure: May be due to poor compliance, poor drug absorption, immunosuppression, or resistance. Consider:

  • Partial nail removal
  • Alternative antifungal drug
  • Complete nail removal in combination with further antifungal therapy 3

Efficacy Considerations

• Topical treatments show variable success rates (20-70%) depending on the extent of infection 1
• Systemic therapy is almost always more successful than topical treatment but should be reserved for cases unresponsive to topical therapy 1
• Mycological cure rates are typically about 30% better than clinical cure rates 1
• Fungicidal drugs (terbinafine, naftifine, butenafine) are generally preferred over fungistatic drugs (azoles) for dermatophyte infections 6
• Azole drugs are often preferred for Candida infections 6

By following this treatment approach, most fungal infections of the nail fold can be effectively managed, improving patient outcomes and quality of life.