Causes
Onychomycosis is caused by fungi that invade the nail plate and nail bed, most often dermatophytes like Trichophyton rubrum. Infection usually starts when fungi enter through tiny cracks in the nail or surrounding skin, especially in warm, moist environments. Walking barefoot in communal showers, wearing tight shoes, or having athlete’s foot increases the chance of nail infection. Weakened immunity, diabetes, and poor circulation also make it easier for the fungus to take hold.
