Nail & Skin Disorders

Green Monsters

Fungal infections of the nails are to nail salons what Elvis sightings are to the National Enquirer — rumored to be everywhere but with no documented proof.

Fungal infections of the nails are to nail salons what Elvis sightings are to the National Enquirer — rumored to be everywhere but with no documented proof.

While it’s true that fungal infections of the nails do exist (and yes, we can prove it), they are much less prevalent than nail technicians and their clients think. “Fungus” has become the catch-all word used in salons to describe a variety of nail disorders ranging from pseudomonas bacterial infections (characterized by green on or under the nail plate) to allergic reactions to diseases such as psoriasis. Ironically, nail technicians, at least, rarely get to call a fungal infection by its true name because they hardly ever see one.

“There have been studies that show only about 50% of all nail disorders are fungal infections,” says Phoebe Rich, M.D., a dermatologist in Portland, Ore.

Outside dermatologists’ offices, fungal infections of the nails are even less common, says Richard K. Scher, M.D., head of the Section for Diagnosis and Treatment of Nail Disorders at Columbia University-Presbyterian Medical Center in New York City and NAILS’ own Nail Doctor. “It’s estimated about 10% of the American population has a fungal infection of the nails, although I think it could be as high as 15% to 20%.”

So why does everyone use “fungal infection” as a blanket term for nail disorders? Because a fungal infection is the most common nail disorder occurring in the general population, says Dr. Scher, and the one everyone is familiar with. Fungal infections are not, however, the most common nail disorder of nail salon clients.

“The frequency of fungal infections in the population of people getting their nails done is very small, probably well below 10%,” he says. “I think it’s amazing it’s not much higher than that, but hair and nails are very strong, vigorous structures and have good resistance to abuse and injury. I also think people visiting salons are healthy individuals conscious of their appearance. In other words, most people with fungal infections have nothing to do with nail salons.”

Still, with 25 million men and women in the United States alone troubled by fungal infections of the nails, you need to be able to recognize what they are, what they’re caused by, and how they are treated so that you can accurately inform your clients.

Fungi Facts

Fungi were long classified as part of the plant kingdom until scientists discovered that they are more chemically and genetically similar to animals than to plants. This information, combined with the fact that fungi absorb nutrients from dead and decaying matter or live plants and animals rather than ingesting them like animals or manufacturing them like plants, spurred the creation of a new monarchy — the fungi kingdom.

Fungal spores (a dormant form of a living fungus organism that can be likened to a plant seed) are present everywhere in the environment, including on the skin. Until they find a food source to “plant” themselves on, however, they remain dormant (inactive).

There are approximately 100,000 identified species of fungi, but only about 100 of them are known to infect animals and humans, and only about eight of those commonly affect the nails. Fungi are broken down into as many as seven classifications depending on how they reproduce, but for understanding fungal infections of the nails nail technicians need only be concerned with two broader classes — yeasts and dermatophytes. These two classes differ in the nutrients they need to survive.

Dermatophytes are a highly specialized group of fungi that break down keratin (the protein that makes up hair and nails) and absorb its nutrients. But just one dermatophyte, trichophyton rubrum, is responsible for most fungal infections of the nails. In fact, this dermatophyte reportedly is responsible for more than 80% of fungal infections of the nails (tinea unguium), 95% of athlete’s foot infections (tinea pedis), 90% of jock itch infections (tinea cruris), and more than 50% of ringworm infections of the body (tinea corporis).

Yeasts are another specialized segment of the fungi kingdom that survive on sugar rather than keratin. Candida albicans is the most common yeast organism to infect humans and is found naturally on mucous membranes in the vagina and mouth and in the gastrointestinal tract, where it is usually held in check by normal bacteria and body defenses.

Yeast infections also can develop under the proximal nail fold (called paronychia) and as a secondary infection between artificial product and the nail plate and under a nail plate that has separated from the nail bed.

Paronychia is very common, as are secondary yeast infections under artificial nails and in nails that have separated from the nail bed. However, while yeast is a type of fungus, paronychia is not a fungal infection of the nails because it is the proximal nail fold, not the nail, that is infected. Even when a yeast infection occurs under the nail, it is a secondary infection and is not the cause of the separation. (For more on yeast infections, see “Cooking Up Yeast Infections,” page 97.)

Types of Fungus

A true fungal infection of the nail is called onychomycosis. The most common type of fungal infection of the nail, distal subungual onychomycosis, begins with a small separation between the end of the nail and nail bed, says Dr. Scher. When the infection begins near the cuticle it is called proximal subungual orrychomycosis. With both types of infection, soft yellow material gradually builds up in the separation and the nail will thicken and yellow. Brown, gray, black, or green by-product of the fungi often are present. Untreated, the infection will progress toward the matrix, resulting in a partially destroyed, misshapen, yellow nail. A third type of fungal infection, which appears mainly on toenails, is called white superficial onychomycosis and is characterized by isolated white islands on the nail surface.

As mentioned earlier, fungal spores are everywhere. To infect the nails, fungi need a “portal of entry” to reach the nail bed, where dermatophytes enjoy a ready food source of keratin as well as a warm, moist environment in which fungi thrive. The portal of entry usually comes from trauma to the nail, such as an injury or allergic reaction to nail products, which causes a small separation of the nail plate from the nail bed and allows fungus to “move in” under the nail.

Fungal infections are found much more commonly on the toenails than on fingernails, says Dr. Rich. “True fungal infections of the fingernails are about one- tenth as common as on the toenails.”

Fungal infections of the toenail are more prevalent because the toenails are exposed to so much more trauma and abuse than fingernails. The feet also are much more susceptible to fungal infections of the skin, which can spread to the toenails, because the feet spend much of their time encased in socks or stockings and shoes, which foster the dark, moist environment fungi thrive in.

“When it comes to toenails, there doesn’t have to be a portal of entry. Many believe a person can’t get a nail infection without a skin infection first,” says Dr. Scher. “I think the majority of toenail infections are preceded by fungal skin infections, but not always. In fingernails it’s believed the portal of entry is due to a microscopic injury because many people don’t have a skin infection on the hands, and the majority of infections on the fingernails start under the nail,” he says.

Fungal infections of the fingernails, in feet, appear to be related to fungal infections of the toenails. “Fungal infections of the fingernails are almost always accompanied by a skin infection on the hands and fungus of the toenails,” says Dr. Rich. “There’s generally a light scaly disorder on the palms. And there’s an interesting phenomenon called “two foot, one hand disease” where we see fungal infections of the toenails on both feet and on a few nails of one hand.”

With fungal spores everywhere in the environment and with fingernails and toenails subjected to so much trauma (their anatomical function is, after all, to protect the delicate nerve endings at the tips of fingers and toes), it’s a wonder more people don’t get fungal infections, says Dr. Scher.

“There seems to be a genetic predisposition to fungal infections, so if you’re born into a family that has fungal infections then you’re likely to get them,” says Dr. Rich. “Studies have shown there’s a genetic glitch in the immunity to them so if you inherit that glitch you are more likely to get one.”

“Fungal infections aren’t very contagious,” Dr. Scher agrees. “They can be transmitted, but it’s not easily done. That’s why you see couples who’ve been sleeping together for 50 years and one has it and the other doesn’t”

Fungus and Artificial Nails

Fungal infections are often attributed to artificial nails, but it’s been an unfair rap. Yeast infections and pseudomonas bacterial infections (see “Shades of Green” on page 92) are closely associated with artificial nails, but artificial nails don’t cause fungal infections, Dr. Scher says. “If someone is wearing artificial nails and gets a fungal infection, there is a connection, but the artificial nail is not the direct cause.”

Exactly what role artificial nails play in the development of fungal infections of the nails is not clear, but most dermatologists agree that anything that covers the nails, including artificial nails or nail polish, can block the transfer of air and moisture between the nail bed, the nail plate, and the environment.

“What we think is that there are some people who put artificial nails on and never remove them. When you do that you block the transfer of moisture and air across the nail plate and that causes an accumulation of moisture under the nail plate, which sets up the conditions for a fungal infection because fungi thrive in moisture.”

Adds, Dr. Rich, “Water is normally evaporated from the nail bed and nail products act as barriers to its evaporation, so these types of infections can be more common in wearers of nail products, but it can’t just be the water buildup because so many people wear them without problems.”

However, the fungi still need access to the nail bed, which can stem from an injury to the nail plate — ranging from banging the nail hard enough to separate the product and create a microscopic tear in the nail plate or the hyponichium (where the nail plate and nail bed seal together at the nail’s free edge) to over-vigorous etching of the nail plate before applying product.

As for preventing fungal infections in the nail salon, there’s not much to be done, says Rich. “I think for the most part clients can feel safe being serviced by a skilled manicurist and when the nails are properly maintained and kept at a reasonably short length. I tell patients not to let the nails project much beyond the tip of the finger because as soon as you bump the nail and tear it loose from the nail bed you’re open to infection.

“Certainly if implements aren’t cleaned that could be a source of infection, but I think most salons are conscious of that. It can happen with people who do their own nails and repairs, but I think it’s mostly to do with the nail itself. Every time you do something to the nail — whether you bang it or file it — it loosens the cells that keep it firmly attached.”

Making the Call

The widespread misidentification of fungal infections is not limited to nail technicians alone — even doctors often make the wrong call. That’s because there are a number of conditions — including psoriasis, lichen planus, alopecia areata, congenital nail dystrophies, cancer of the nails, and onycholysis due to an allergic reaction or trauma to the nail—that can resemble a fungal infection, even to a doctor’s trained eye.

“Some form of diagnostic test needs to be done. If a physician just looks ant says it’s a fungal infection, he’ll only bright half the time,” Dr. Scher says. This is because only half of all nail disorders are fungal. “A physician should not treat a fungal infection without a diagnostics test because it could be an allergic reaction, trauma, or psoriasis.”

Fungal infections can be diagnosed by a KOH wet mount or a culture — tests that must be performed by a physician.

Hard to Get and Get Rid Of

Because fungal infections are rooted under the nail plate, they are difficult to treat Topical antifungals don’t work on fungal infections of the nails because they can’t get to the fungi effec­tively enough to kill them. In fact, several years ago the FDA began to disallow the labeling of topical antifungals as effective against fungal infections of the nails and hair.

Still, many nail technicians swear that some topical antifungals, and home remedies such as diluted bleach or vinegar, are effective cures for fungal infections of the nails. “A lot of nail conditions are self-healing,” explains Dr. Rich, saying some conditions called fungal infections are nail disorders that would have healed without any treatment Additionally, other conditions, such as yeast infections and pseudomonas infections, sometimes can be effectively treated with topical antifungals and antibiotics or home remedies.

While no physician will go as far as to advocate home remedies or even delaying the referral of a client to a dermatologist for treatment of a nail disorder, both Dr. Rich and Dr. Scher say there is usually no harm in a client choosing to try over-the-counter treatments for a few weeks before consulting a dermatologist.

“There is some risk if diagnosis is delayed, but fortunately it’s not too much of a problem,” says Rich, who recommends not letting too much time lapse between noting the condition and seeking professional treatment. If there are black streaks in the nail, a symptom of melanoma cancer under the nail, the client should seek immediate medical attention.

Until recently, physicians’ choices were fairly limited in treating fungal infections of the nails. Griseofulvin and Ketoconazole were the two oral antifungals available, and both took a year or more of treatment and carried the risk, albeit minor, of liver damage. Also, both antifungals were only effective against a few fungi species.

Today, new antifungals introduced in the past few years are effective against a broader spectrum of fungi, have less severe side effects, and require a shorter course of therapy.

“Itraconazole [marketed under the brand name Lamisil] and terbinafine are better alternatives. The biggest difference from the older medications is that they stay in the nail a lot longer,” Dr. Scher says. “With Griseofulvin the patient had to take it for six months to treat the fingernails and 12 months to treat the toenails. With these new medications the patient takes it six weeks for the fingernails and 2-5 months for the toenails, although the length of time depends on how severely the nail is affected.

Shades of Green

The most common nail disorder confused with a fungal infection of the nails by nail technicians is actually a bacterial infection. Caused by the pseudomonas aeruginosa bacteria, the infection results in a yellow-green, green, or green-black stain on the nail caused by pyocyanin pigment produced by the bacteria Other symptoms of a bacterial nail infection include pus, separation of the nail plate from the nail bed, and abnormal nail growth.

Pseudomonas is a water-borne bacteria, which means it’s transmitted through water and thrives in a warm, moist environment It occurs so commonly in the salon because When artificial nails lift, moisture can seep in between the artificial product and the natural nail bed.

On top of the nail, pseudomonas is usually a primary infection caused by this moist pocket between the artificial and natural nails. At other times, though, it occurs under the natural nail and is considered a secondary infection, which means the bacteria didn’t cause the separation between the nail plate and nail bed; it just simply took advantage of the ideal conditions created by trauma to the nail plate that caused it to separate from the nail bed.

Fortunately, treating a pseudomonas infection is much simpler than a fungal infection. If the green discoloration is the only symptom, you often can treat the infection in the salon by removing the artificial product from the nail and letting the nail plate dry out.

“To treat a pseudomonas infection caused by loosened product, remove the artificial product and apply diluted white vinegar,” says Dr: Phoebe Rich. “This will kill the organism.” Other options include applying diluted bleach (one part bleach to 20 parts water) or a mixture of equal parts dear tincture of iodide and rubbing alcohol.

While this usually kills the pseudomonas bacteria immediately, the green stain caused by the pigmentation the bacteria produced as a by-product will usually remain on the nail until it grows out. If the infection was on top of the nail, you can lighten the stain by lightly buffing it with a fine-grit buffer. To remove it completely; Dr Rich recommends applying a drop of bleach directly to the stain. If the color still remains, that means it is deeply embedded in the nail plate and will take several months to grow out.

“As for whether you can reapply the product right away! I’m not sure,” Dr: Rich adds. “There’s usually something else going on to cause the infection.”

If the natural nail has separated from the nail bed and the infection is underneath the nail, or if there are other signs of infection — redness, swelling, pus — around the nail, you should definitely remove the product from at least that nail until the client sees her doctor In cases like this, the infection is secondary to another nail condition that requires a doctor’s attention If the natural nail has separated from the nail bed, the doctor will most likely trim away the lifted portion of the nail to expose it to air and so that topical antibiotics can be applied to kill the bacteria.

Cooking Up Yeast Infections

Anyone who’s ever baked bread knows that yeast must be activated in warm water. The same is true even on the skin: Yeast, which is a form of fungus present everywhere in nature, thrives in dark, warm, moist places. On nails, yeast infections commonly occur under the proximal nail fold and under lifted artificial product or nails that have separated from the nail plate.

Yeast infections under the proximal nail fold, called paronychia, are especially common with people who are commonly exposed to water: housewives, doctors, nurses, bartenders, dish­washers, etc. It can also occur in people who bite their nails or cuticles or when the cuticles are pushed back too vigorously, breaking the seal between the nail plate and the cuticle.

The condition usually appears with swelling and redness of the cuticle area accompanied by a white or greenish discharge. Mild cases of paronychia ran be treated by soaking the affected area in warm saline water for 10-15 minutes 2-4 times a day. It also can be cleaned with over-the-counter antifungal treatments such as clotrimazole or miconazole creams. If the infection doesn’t clear up completely in a week or two, or if it gets worse, the client should see her doctor immediately The client should wear gloves with cotton inserts whenever she does “wet work” while her infection is being treated.

When a yeast infection occurs under the nail plate, it is usually secondary to another nail condition and requires a doctor’s treatment. A doctor will most likely trim away the separated nail and treat the infection with a topical antifungal. More severe infections may require treatment with oral antifungals.


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