Fingernail fungus is typically identified by nails that are thickened, brittle, crumbly or ragged. Infected fingernails may also be distorted in shape, have a foul odor, appear dull or be dark in color. Specific signs of nail infections differ based on the type of infection that affects the nails.
There are four major types of fungal nail infects that can affect both fingernails and toe nails. They include distal subungual onychomycosis, white superficial onychomycosis, candida onychomycosis and proximal subungual onychomycosis. Candida onychomycosis is more commonly seen in fingernails rather than toe nails.
Candida onychomycosis is a yeast infection of the nail that may also affect the skin that borders the nail inside of the nail folds. All of the fingernails may become infected at the same time. Candida onychomycosis causes nails to separate from the nail bed. As the infection takes over weakened areas of the fingernail, the nail may become discolored. If this occurs, the nail may turn white, green or brown, and begin to take on an odd shape.
Another sign of a candida onychomycosis infection is a nail that appear thicker than normal. The folds of skin that surround the nail may become reddened, swollen, tender, or warm. This type of nail infection typically causes pain, unlike other types of fungal nail infections.