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Onychomycosis (cont.)

Causes of Onychomycosis

Onychomycosis is caused by three main classes of organisms: dermatophytes (fungi that infect hair, skin, and nails and feed on nail tissue), yeasts, and nondermatophyte molds. All three classes cause the very similar early and chronic symptoms or appearances, so the visual appearance of the infection may not reveal which class is responsible for the infection. Dermatophytes (including Epidermophyton, Microsporum, and Trichophyton species) are, by far, the most common causes of onychomycosis worldwide. Yeasts cause 8% of cases, and nondermatophyte molds cause 2% of onychomycosis cases.

  • The dermatophyte Trichophyton rubrum is the most common fungus causing distal lateral subungual onychomycosis (DLSO) and proximal subungual onychomycosis (PSO).
  • The dermatophyte Trichophyton mentagrophytes commonly causes white superficial onychomycosis (WSO), and more rarely, WSO can be caused by species of nondermatophyte molds.
  • The yeast Candida albicans is the most common cause of chronic mucocutaneous candidiasis (disease of mucous membrane and regular skin) of the nail.

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Onychomycosis - Treatment

What effective treatments have you found for fungal nail infections?




Read What Your Physician is Reading on Medscape

Onychomycosis »

Onychomycosis (OM) refers to a fungal infection that affects the toenails or the fingernails.

Read More on Medscape Reference »


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