Types of Toe Nail Fungus

There are many types of toenail fungus, and they all vary based on the type of infection present and how long it lasts. But they also all have one thing in common: They thrive in warm, moist areas like shoes, socks and locker rooms. All types may bring discolored, hardened nails that are embarrassing to show others.

Distal Subungual Onychomycosis (DSO or DLSO)

This is the most common nail fungus, often originated by the organism Trichophyton rubrum. It affects the area around the toe, along the tip of the nail and both sides of the nail. Once the fungus invades the nail, it may become discolored, turning white, yellow or green, and become hard and brittle.

White Superficial Onychomycosis (WSO)

WSO only affects 10 percent of toenail fungus sufferers, and is caused by Trichophyton mentagrophytes. It only affects the outer bed of the nail, making it easier to heal with topical products, such as Lamisil. The nail plate turns white, which, in the early stages, can still be scraped off.

Proximal Subungual Onychomycosis (PSO)

The least-common type of fungus is also caused by Trichophyton rubrum, and in the early stages, the nail bed may be appear discolored and look yellow. If it is left untreated, the fungus will progress deeper into the nail, and the nail will become hard and thick and may cause pain.

Candida Nail Infection

While the yeast infection of the nail tends to affect fingernails more than toenails, it can affect both. The nail plate begins to cause pain and become discolored, and if it worsens, may separate from the nail bed.

Black Nail Fungus

Black Nail Fungus occurs rather frequently because its main cause is the occurrence of blood under the nail. Left untreated, the toenail will grow in darker when it grows back. In rare instances when a toenail fungus is severe, it becomes discolored, and instead of turning yellow, it will turn brown or black.