An 8-year-old boy presents with itching between his toes for 1 month (Figure 125-1). The pediatrician looks between his toes and sees maceration with white material. The patient was diagnosed with tinea pedis and treated successfully with a topical nonprescription antifungal medication.

Tinea pedis is a common cutaneous infection of the feet caused by dermatophyte fungus. The clinical manifestation presents in 1 of 3 major patterns: interdigital, moccasin, and inflammatory. Concurrent fungal infection of the nails (onychomycosis) occurs frequently.

Athlete’s foot.

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  Tinea pedis is thought to be the world’s most common dermatophytosis.¹

  
  
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  70 percent of the population will be infected with tinea pedis at some time.¹

  
  
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  More commonly affects males than females.¹

  
  
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  Prevalence increases with age and it is rare before adolescence.¹

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  A cutaneous fungal infection most commonly caused by Trichophyton rubrum.¹

  
  
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  Trichophyton mentagrophytes and Epidermophyton floccosum follow in that order.

  
  
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  T. rubrum causes most tinea pedis and onychomycosis.

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  Male gender.

  
  
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  Use of public showers, baths, or pools.²

  
  
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  Household member with tinea pedis infection.²

  
  
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  Certain occupations (miners, farmers, soldiers, meat factory workers, or marathon runners).²

  
  
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  Use of immunosuppressive drugs.

Typical Distribution and Morphology

Three types of tinea pedis:

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  Interdigital type—Most common (Figure 125-2).

  
  
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  Moccasin type (Figure 125-3).

  
  
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  Inflammatory/vesicular type—Least common (Figure 125-4).

Some authors describe an ulcerative type (Figure 125-5).

Clinical Features