The most common disorder your clients are likely to experience is a bacterial infection in the nail caused by an organism called Pseudomonas aeruginosa. The infection usually occurs after a minor injury to the nail and is characterized by a greenish-black discoloration of the nail plate. Sometimes, the nail will separate from the nail bed. This bacterial infection isn’t usually painful, although the affected nail may be tender. A dermatologist usually treats a Pseudomonas infection by trimming back the separated nail, cleaning the nail bed, and applying a prescription topical antibiotic. More severe infections may require oral antibiotics, as well. If there is just a green discoloration on the nail and the nail has not started to separate from the nail bed, the nail technician can treat it by cleansing the nail well with hydrogen peroxide.

The second most common nail disorder is a yeast infection. It appears in one of two forms: The more frequent is redness and swelling around the nail, particularly adjacent to the cuticle. This is called paronychia and is caused by a yeast organism called Candida albicans. The same yeast organism also causes the second form of yeast infection, called onycholysis. Both types of yeast infection respond to external anti-yeast agents such as mycostatin. If this over-the-counter medication doesn’t work within a few weeks, the nail technician should refer her client to a dermatologist.

Another common nail infection is called onychomycosis, also known as a fungal infection of the nail. The fungus most commonly responsible for a nail infection is called trichophyton rubrum. The symptoms of a fungal infection of the nail include thick, yellow nails and a thick nail bed. Sometimes part or all of the nails falls off or is noticeably separated from the nail bed. When the nail is very thick, the patient may feel pain and tenderness. In the case of a bad toenail infection, the patient may not be able to wear shoes comfortably.

A fungal infection of the nail can appear in three ways. Most commonly, the tip of the fingernail or toenail will be infected, which is called a distal subungal infection. When the infection occurs near the cuticle, it is called a proximal subungal infection. The type that occurs mainly on toenails is referred to as a white superficial infection. It manifests as isolated white islands on the nail surface.

Treatment of all three fungal infections begins with an antifungal cream, gel, or lotion. If one of these topical preparations doesn’t work, a dermatologist will prescribe an oral antifungal.

With all nail infections-whether they are caused by bacteria, yeast, or fungus-it is important to culture the nail. This way the culprit causing the infection is positively identified and the most effective treatment can be chosen.

The fourth disorder is caused by an allergic reaction, not by an infection. The two most common sources of allergic nail reactions are formaldehyde and acrylic products. Formaldehyde and formaldehyde resins are often found in nail enamels. Acrylics can be found in sculptured nail components, nails glues, and in some nail strengtheners. An allergic reaction to formaldehyde and acrylic is marked by redness, swelling, and oozing around the nail. Sometimes, small blisters will appear, and the client may complain of tenderness and itching around the nail, as well. The nail may separate from the nail bed with more severe reactions.

If a client exhibits any these symptoms after you apply a product to her nails, remove the product immediately and wait until the symptoms disappear before doing anything else to her nails. If the reaction is severe, she may need to see a doctor for an oral cortisone medication.

Once the symptoms have cleared, you may again work on the clients nails, but don’t use the product that caused the reaction. If a client is allergic to formaldehyde, then use only formaldehyde free products on her nails. If a client is allergic to acrylics, don’t apply acrylic or gel nails or use nail glues or nail strengtheners that contain acrylics. If you’re not sure what she’s allergic to, send her to her doctor with a list of the products (and their ingredients) that you use.

You can lessen the likelihood of any of these nail disorders occurring with your clients by paying close attention to your clients’ cuticles. The cuticle is an abused and mistreated structure, but it performs a very important function: It protects the proximal nail fold and the matrix by sealing the proximal nail fold to the nail, blocking out invading organisms. If the cuticle is pushed too hard by wooden or metal instruments or if it is cut away with nippers or scissors, the “seal” is broken, allowing bacteria and fungi and other harmful irritants to reach the matrix. Therefore, it is essential to treat the cuticles with respect. If the cuticles need attention, it is best to soften them and then push them back gently with a moist towel or wash-cloth. Cuticle softeners, when used correctly and carefully, may also be applied.

Richard K. Scher, M.D., is a dermatologist specializing in nails. He is Professor of Dermatology and head of the Section for Diagnosis and Treatment of Nail Disorders at Columbia University-Presbyterian Medical Center in New York City. Dr. Scher is an internationally-known expert and pioneer in nail disease treatment and surgery. His textbook on nails is the premier work in this area. Dr. Scher has also published over 200 articles on the subject and lecturer extensively to both medical and lay groups.

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