Fungal Nail Infection: An Overview
Learn more about fungal nail infection diagnosis and treatments

Fungus causes the most common infection of the nails; in fact, fungal nail infections, or onychomycosis, are more common on the toenails than the fingernails and affects about 12% of all Americans.
Types of Fungal Nail Infection
The two most common types of fungi that affect the skin are dermatophytes and yeast. Dermatophytes may be more often seen in toenails and yeast type in fingernails, although both types infect all nails. Since the treatment could be different, it may be important to identify the type of infection.
Diagnosing Fungal Nail Infections
To treat and diagnose the problem, the dermatologist may take samples from the nail in order to properly identify the cause. The dermatologist takes a nail scraping and treats it with a chemical called KOH which allows it to be examined under a microscope. The scrapings from under the nail may sometimes be used to culture the material to see what grows and identify it.
A nail sample may be sent to a laboratory as a biopsy where a PAS test helps identify fungal strands. Other conditions may look like fungal infections, but they are not. These conditions include nail psoriasis or allergic reactions to nail polish, hardeners, or acrylic nails. These tests therefore help pinpoint the diagnosis.
Awareness of fungal infection of the nails is also important in people who have other diseases such as diabetes, and those who have had their immune system suppressed. Patients who are HIV positive, those undergoing chemotherapy treatments, or transplant patients who are also taking drugs which suppress the immune system, should all be treated to prevent future health problems due to fungal nail infections.
Treatment
Treatments include topical antifungal creams, lotions, gels, and lacquers, although these may have difficulty penetrating the nail.
Oral medicines like terbinafine, itraconazole, and fluconazole are also used, and may require monitoring with blood tests. These new internal treatments are very safe when monitored by the dermatologist. In general, toe and fingernail fungus usually requires pills except in very mild cases. These medications should be avoided in patients with a history of liver problems such as hepatitis and are not given to pregnant or nursing women. Debridement or removing the infected part of the nail may enhance the effectiveness of the treatment. Dissolving or surgically removing the nail if the nail is thick and deformed may be helpful in a few situations, and used only if the infection is very severe.
Recurrence and Prevention
To prevent future nail infections, always wash and dry the feet properly and never share clippers and files. Additionally, cleanse all foot instruments with alcohol to get rid of contamination.
It is best to avoid being barefoot in public places such as pools and locker rooms. Never share shoes with others and wear outside shoes for outside work. Keep antifungal sprays on hand to spray your shoes with regularly. Shoes should fit properly and not cramp your feet.