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Diseases and Conditions
Nail fungusFrom MayoClinic.com
Special to CNN.com
An infection of nail fungus (onychomycosis) occurs when fungi infect one or more of your nails. Onychomycosis (on-i-ko-mi-KO-sis) usually begins as a white or yellow spot under the tip of your fingernail or toenail. As the nail fungus spreads deeper into your nail, it may cause your nail to discolor, thicken and develop crumbling edges — an unsightly and potentially painful problem.
Infections of nail fungus account for about half of all nail disorders. These infections usually develop on nails continually exposed to warm, moist environments, such as sweaty shoes or shower floors. Nail fungus isn't the same as athlete's foot, which primarily affects the skin of the feet, but at times the two may coexist and can be caused by the same type of fungus.
An infection with nail fungus may be difficult to treat, and infections may recur. But medications are available to help clear up nail fungus permanently.
Signs and symptoms
You may have a nail fungal infection if one or more of your nails are:
Infected nails may also separate from the nail bed, a condition called onycholysis. You may even feel pain in your toes or fingertips and detect a slightly foul odor.
Fungi are microscopic organisms that don't need sunlight to survive. Some fungi have beneficial uses, while others cause illness and infection.
Nail fungal infections are typically caused by a fungus that belongs to a group of fungi called dermatophytes. But yeasts and molds also can be responsible for nail fungal infections. All of these microscopic organisms live in warm, moist environments, including swimming pools and showers. They can invade your skin through tiny invisible cuts or through a small separation between your nail and nail bed. They cause problems only if your nails are continually exposed to warmth and moisture — conditions perfect for the growth and spread of fungi.
Infection with nail fungus is more common in toenails than in fingernails because toenails are often confined in a dark, warm, moist environment inside your shoes — where fungi can thrive. Another reason may be the diminished blood circulation to the toes as compared with the fingers.
Nail fungus is more common among older adults because nails grow more slowly and thicken with aging, making them more susceptible to infection. Nail fungus also tends to affect men more than women and those with a family history of this infection.
However, these factors can increase your risk of developing nail fungus:
You're also more likely to develop nail fungus if you have:
When to seek medical advice
Once a nail fungal infection begins, it can persist indefinitely if not treated. See your doctor at the first sign of nail fungus, which is often a tiny white or yellow spot under the tip of your nail.
Nail fungal infections can be painful and may cause permanent damage to your nails. They may also lead to other serious infections that can spread beyond your feet.
In addition, they can pose a serious health risk for people with diabetes and for those with weakened immune systems. If you have diabetes, your blood circulation and the nerve supply to your feet can become impaired. Therefore, any relatively minor injury to your feet — including a nail fungal infection — can lead to a more serious complication, such as an open sore (foot ulcer) that's difficult to heal. See your doctor immediately if you suspect nail fungus.
Screening and diagnosis
The first step to beating nail fungus is getting a diagnosis. Your doctor will likely examine your nails first. To test for fungi, your doctor may scrape some debris from under your nail for analysis.
The debris can be examined under a microscope or cultured in a lab to identify what is causing the infection. Other conditions, such as psoriasis, can mimic a fungal infection of the nail. Microorganisms, including yeast and bacteria, also can infect nails. Knowing the cause of your infection helps determine the best course of treatment.
Nail fungus can be difficult to treat, and repeated infections are common. Over-the-counter antifungal nail creams and ointments are available, but they aren't very effective. Fortunately, other nonsurgical treatments have been introduced during the last 10 years.
These medications help a new nail grow free of infection, slowly replacing the infected portion of your nail. You typically take these medications for six to 12 weeks but won't see the end result of treatment until the nail grows back completely. It may take four to 12 months to eliminate an infection. Recurrent infections are possible, especially if you continue to expose your nails to warm, moist conditions. Antifungal drugs may also cause side effects ranging from skin rashes to liver damage. Doctors may not recommend them for people with liver disease or congestive heart failure or for those taking certain medications.
Other treatment options
If your nail infection is severe or extremely painful, your doctor may suggest removing your nail. A new nail will usually grow in its place.
To help prevent nail fungus and reduce recurrent infections, practice good hand and foot hygiene by following these steps:
August 25, 2005