Diagnosis and Management of Chronic Peeling Feet Without Erythema
Despite the negative fungal test, this presentation is most consistent with squamous hyperkeratotic tinea pedis (moccasin-type), and you should obtain repeat fungal testing with proper technique before initiating topical terbinafine 1% cream twice daily for 2 weeks, combined with urea 10% cream three times daily.
Clinical Reasoning
The 2.5-year history of asymptomatic, light-colored peeling skin on the soles and between toes without redness is the classic presentation of squamous hyperkeratotic tinea pedis, even with a prior negative fungal test 1. The American Academy of Pediatrics specifically notes that this form typically presents with light-colored scaling and peeling skin on the soles and margins of the feet without symptoms 1.
Why the Negative Fungal Test May Be Misleading
- Sampling technique matters critically: The specimen must be obtained from the active border of the lesion using proper scraping technique to ensure a higher chance of isolating the infecting fungus 2
- False negatives are common: The accuracy of clinical diagnosis and initial testing for tinea pedis is known to be low 3
- Repeat testing is warranted: The Infectious Diseases Society of America recommends obtaining a KOH preparation or fungal culture from skin scrapings before initiating treatment 1
Recommended Treatment Approach
First-Line Topical Therapy
Apply topical terbinafine 1% cream twice daily to the bottom and sides of both feet for 2 weeks, as this is superior to other topical agents for dermatophyte infections 1. The American Academy of Pediatrics specifically recommends this regimen for this presentation 1.
Essential Adjunctive Measure
Apply urea 10% cream three times daily to reduce hyperkeratosis and improve penetration of antifungal agents 1. This addresses the thick, peeling skin that has persisted despite Aquaphor use 4.
When to Consider Oral Therapy
If topical therapy fails after 2 weeks or if the involvement is extensive, oral terbinafine 250 mg once daily for 2 weeks provides similar mycological efficacy to longer courses with faster clinical resolution 1. The European Academy of Dermatology and Venereology supports this approach for extensive involvement 1.
Critical Preventive Measures to Avoid Recurrence
The 2.5-year duration suggests ongoing reinfection or inadequate treatment. Address these factors:
- Ensure complete drying of feet after bathing, particularly between toes 1
- Apply foot powder after bathing to maintain dryness—this can reduce recurrence rates from 8.5% to 2.1% 4, 1
- Treat footwear: Shoes can harbor large numbers of infective fungal elements. Either discard old footwear or place naphthalene mothballs in shoes within a tightly tied plastic bag for minimum 3 days, or spray terbinafine solution into shoes periodically 4
- Examine for nail involvement: Check for dystrophic toenails, which commonly coexist with chronic tinea pedis and serve as a reservoir for reinfection 1
Common Pitfalls to Avoid
Do not rely solely on Aquaphor (petrolatum): While petrolatum prevents moisture evaporation 4, it does not treat the underlying fungal infection or reduce hyperkeratosis 4. The 2.5-year persistence despite Aquaphor use demonstrates this limitation.
Do not assume a single negative fungal test rules out infection: The squamous hyperkeratotic form can be caused by Trichophyton rubrum or T. mentagrophytes, which may require proper sampling technique and sometimes repeat testing 1, 3.
Do not ignore interdigital spaces: Carefully examine between toes for fissuring, scaling, or maceration, which serves as a portal for secondary bacterial infection and indicates active fungal infection 1.
Alternative Considerations Only If Fungal Testing Remains Negative
If repeat fungal testing with proper technique remains negative after 2-3 attempts, consider:
- Juvenile plantar dermatosis (though typically affects children)
- Contact dermatitis from footwear
- Psoriasis (though usually has other manifestations)
- Keratolysis exfoliativa (though typically involves hands as well)
However, the distribution (soles, between toes, sparing heels) and 2.5-year chronicity make tinea pedis by far the most likely diagnosis 1, 3.