Fungal infections of the finger/toenails, medically known as either onychomycosis or tinea unguium, are widespread occurrence; yet it is worth noting that nail fungal infections are not highly contagious. A fungal infection may transmit from person to person but only with continuous intimate contact. In fact, approximately 10% of all Western society adults may have a fungal infection at one time with adults 60 years old or older increasing to 20%. Numerous changes to the nails may cause someone to think they have contracted a fungal infection. In reality, abnormal-looking nails may be due to a number of conditions including, but not limited to, a fungal infection. There are many other reasons why your nails may look different. Toenail fungus is more common than fingernail fungus.
There are many species of fungi that can affect nails. By far the most common, however, is called Trichophyton rubrum (T. rubrum). T. rubrum has a penchant for infecting the skin and may manifest in some ways and has been known to cause distal subungual onychomycosis and proximal subungual onychomycosis. Single-celled organisms known as yeast can also cause nail fungus disorders. A particular yeast organism, known as Candida, is known to cause yeast onychomycosis. The most common type of fungal infection (up to 90% of all cases; more in toenails rather than fingernails) is known as distal subungual onychomycosis. A nail fungal infection is caused by a fungus that has developed in warm, humid, and wet environments; for example, improperly sanitized public saunas, pools, salons, or showers. It is well documented that athletes are at a higher risk for contracting a nail fungus. This may be due to athletes wearing sweaty shoes associated with weakening of the toenail through repetitive trauma. As mentioned above, the elderly, as well as those with certain immunosuppressive conditions, are at a higher risk; for example, such conditions as cancer, diabetes, AIDS, as well as some immunosuppressive medications. Suppression of the immune system is likely to make someone more susceptible to a fungal infection.
Typically, a nail fungal infection is no more than a superficial/cosmetic matter. However, some people do experience discomfort and pain. Footwear, activity, and improper trimming of the nails may worsen such symptoms. Common symptoms of distal subungual onychomycosis initially appear as a discoloration at the corner of a big toe progressing towards the cuticle. If not treated, the toenails will become thickened and flaky. There may at times be signs of athlete’s foot in between the toes or skin peeling on the sole. Yeast onychomycosis is more common in fingernails appearing to turn them yellow, brown, white, or thickened. Patients may have associated paronychia (infection of the cuticle) or have this infection in their mouth. Proximal subungual onychomycosis is the least common (approximately 3% of cases) type of fungal nail disorder. It begins at the cuticle and slowly progresses toward the nail tip. If not treated, the toenails will become thickened and flaky.
Since physical examination alone has been determined to be unreliable in diagnosing a fungal nail disorder, we may begin by ordering a nail sampling test. A nail sample is obtained either by clipping the toenail or by drilling a hole in the nail. The nail sample is then sent to a lab to determine if the genetic material of a fungus is present. Such a test can take up to six weeks to get a result.
A treatment plan may include one or more of the following: topical medications (e.g., Ciclopirox, Efinaconazole, and Tavaborole), oral medications (Griseofulvin, Terbinafine, Itraconazole, and Fluconazole), and lifestyle changes (e.g., keeping nails trimmed/filed reducing the amount of fungus). Currently, an oral antifungal therapy is considered the best treatment for toenail fungus because of higher cure rates and shorter treatment duration compared to topical treatment. Although rare, surgical treatment of onychomycosis is available. However, this often only provides temporary relief, and recurrence is common unless additional antifungal medication (oral or topical) is simultaneously used. However, surgical removal may be warranted when the affected nail is associated with other factors such as trauma and or infection. More novel treatments include photodynamic therapy and electric current therapy.