Tinea unguium, also referred to as onychomycosis, is a fungal nail infection often characterized by thick and brittle nails. Infected nails also appear discolored, often turning brown, black, yellow, and white. Another sign of tinea unguium is onycholysis, which is the separation of the nail plate from the nail bed. Fungal infections, like tinea unguium, may affect men and women of all ages, and from all races.
Dermatophytes are fungi that mostly cause infections in the nails as well as in the hair and skin. Dermatophytes can be categorized into three species of fungi that usually infect the nails. These are microsporum, trichophyton and epidermophyton.
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Nail infections caused by these fungi may manifest in a variety of ways. The most common is known as distal subungal onychomycosis, in which the fungal infection usually starts at the affected nail's end, often causing the nail to raise. This type occurs more frequently in the toenails than in the fingernails. The least common kind of fungal nail infection is the proximal subungal onychomychosis. It usually begins at the cuticle or at the infected nail's base, and spreads slowly towards the tip.
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These fungi that are the main causes of tinea unguium are generally found everywhere. They live in the air and soil, and they love moist and humid places. Those with sweaty feet and those who wear tight-fitting shoes are more likely to develop fungal nail infections. Acrylic nails and nail polish may also hinder the nails' ability to breath, thus, making them more susceptible to these infections. Hygienic measures such as frequent washing of the feet and drying the areas between the toes may help prevent tinea unguium.
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Tinea unguium is commonly seen among athletes, military personnel, and those living with an infected family member. The fungi can be transferred from one foot to another through wet floors in locker rooms, bathrooms, and even swimming pools. Also susceptible to develop fungal nail infections are patients suffering from long-term illnesses such as diabetes, and acquired immune deficiency syndrome (AIDS). Individuals with blood circulation problems resulting in less flow of blood to the feet and toes may also have increased tendencies to develop tinea unguium.
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Dermatologists are medical specialists who treat skin and nail infections and diseases. They may request to take a sample of the affected nail and send it to the laboratory to confirm their diagnosis. Antifungal medications, which are taken orally, are usually prescribed to patients with tinea unguium as creams or topical antifungals are often not effective in these cases.