Nail infection, fungal: The most common fungus infection of the nails is onychomycosis.

Onychomycosis makes the nails look white and opaque, thickened, and brittle. Those at increased risk for developing onychomycosis include:

People with diabetes;
People with disease of the small blood vessels (peripheral vascular disease)
Artificial nails increase the risk for onychomycosis because, when an artificial nail is applied, the nail surface is usually abraded with an emery board damaging it, emery boards can carry infection, and water can collect under the nail creating a moist, warm environment favorable for fungal growth.

discoloration (dark streaks, white streaks, or changes in nail color)
changes in nail shape (curling or clubbing)
changes in nail thickness (thickening or thinning)
nails that become brittle.
nails that are pitted.
bleeding around nails.
swelling or redness around nails.

In normal, healthy people, fungal infections of the nails are most commonly caused by fungus that is caught from moist, wet areas. Communal showers, such as those at a gym or swimming pools, are common sources. Going to nail salons that use inadequate sanitization of instruments (such as clippers, filers, and foot tubs) in addition to living with family members who have fungal nails are also risk factors. Athletes have been proven to be more susceptible to nail fungus. This is presumed to be due to the wearing of tight-fitting, sweaty shoes associated with repetitive trauma to the toenails. Having athlete's foot makes it more likely that the fungus will infect your toenails. Repetitive trauma also weakens the nail, which makes the nail more susceptible to fungal infection.

Elderly people and people with certain underlying disease states are also at higher risk. These include anything that impairs your immune system can make you prone to getting infected with the fungus. These include conditions such as AIDS, diabetes, cancer, psoriasis, or taking any

You can prevent many nail abnormalities by taking good care of your nails. Follow these general guidelines to keep your nails healthy:

Do not bite or tear at your nails, or pull on hangnails.
Always use nails clippers.
Keep your nails dry and clean, and trim after you bathe, when nails are still soft.
Using sharp manicure scissors, trim your nails straight across, rounding the tips gently.
If you have a problem with brittle or weak nails, keep them short to avoid breakage. Use lotion on your nails and cuticles to keep the nail and nail beds moisturized.

If you get professional manicures or pedicures, make sure your nail salon is properly certified and that nail technicians use proper sterilization techniques. You should avoid long-term use of nail polish and nail polish removers.

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