A nail fungal infection appears when a fungus attacks a toenail, fingernail, nail bed, or the skin under the nail. Fungi can attack the nails through small cuts in the skin surrounding the nail or through the space between the nail and nail bed. If the person is healthy, nail fungus infection won’t be a serious concern. This can become a problem when you suffer from diabetes or have a weakened immune system.
A nail that has been infected with a nail fungus may become yellow or white, become thicker and harder to trim, and crumbly. It may also split and separate from the skin. The infected nail may make it painful or uncomfortable to wear shoes, walk, or stand. It may cause permanent damage to the infected nail.