The Nail Doctor

You groan and the client grimaces and sometimes panics. After all, she’s heard about fungal infections on the nails. Contrary to popular belief, however, a green discoloration does not automatically mean a fungal infection. In fact, green nails are almost always caused by bacteria, not fungi. Other symptoms of a bacterial nail Infection include the presence of pus, separation of the nail plate from the nail bed, and abnormal nail growth.

Green nails occur in a number of different circumstances. For our purpose green nails are most often caused by a bacteria called Pseudomonas aeruginosa.

Pseudomonas aeruginosa emits a group of chemicals that produce a greenish discoloration of the nail. This often occurs when there have been pockets of wetness on or around the nail. The wetness can build up in nails that have chronic paronychia (a skin infection marked by inflammation, pus, and pain around the nail folds), wetness adjacent to a cut or laceration, water trapped under an acrylic nail, or a fingertip that has been constantly bandaged.

The green color present on a nail is merely a stain, not a living organism. For example, I often will see a patient who had a prior nail disease. The organisms may be gone, but the green color remains until the nail grows out. If the infection is no longer present the color will grow out leaving a healthy nail behind.

The presence of pseudomonas does not mean that it is causing the infection. When one looks at the presence of any organism in a diseased nail, one must not accept its simple presence as being the cause of the symptoms.

An organism that is capable, all by itself, of inducing disease causes a “primary infection.” If the organism didn’t initiate the disease but is adding to the disease process, it is called a “secondary infection.” Wet nails, for example, may cause a primary infection such as yeast infection. Pseudomonas may then enter the infected area as a secondary infection.

By itself pseudomonas is usually a harmless organism found in healthy people that will colonize in wet areas. Occasionally, for example, a person will leave a small wound bandaged for a week or so. When the bandage is removed, the wound and bandage are green. Leaving these lesions open to the air or simply drying them out with alcohol cleans the lesion and will eliminate pseudomonas. Likewise, artificial nails that lift are prime real estate for pseudomonas. Water seeps in between the artificial product and the natural nail bed, a breeding ground for pseudomonas.

Treatment of a pseudomonas infection is fairly simple, but “when in doubt, refer it out” is probably your safest action. If your client is reluctant to go to a doctor and the green discoloration is the only symptom present, there are several steps you can take in the salon. Although pseudomonas is often a secondary infection, I still see it in my practice as a primary infection caused by bandages or acrylic lifting on the nails.

I use an alcohol antibiotic to treat patients, but there are several other remedies that can be just as effective. For example, a diluted solution of sodium hypochloride has been used to treat the infection since before World War I and is available in grocery stores as bleach (Clorox, Purex, and others). Most retail bleaches are 5% solutions. Dilute the mixture, adding one part bleach to 20 parts water. Bleach acts as a broad antibacterial solution, and has whitening properties as well. Apply a small amount of the solution with a cotton ball, then have the client wash her hands. Vinegar, although less appealing to the nose, also works well.

Polysporin spray (available over the counter) is also effective against the organism when it is just a secondary invader around the nail. This can be used directly on the nail, and you can suggest that clients apply it at home several times per day.

A doctor’s referral is always recommended even if the condition appears minor but you must refer the client t a physician when there are other signs of infection-pus, swelling, redness-or if there are signs of another condition. If the nail is separated from the bed, is crumbling or peeling, or exhibits other abnormalities, it is more than likely that the bacterial infection is only secondary to another condition that requires physician’s attention.

Once the bacteria is killed, the green discoloration often remains. I the color is on top of the nail, you can simply gently scrape or file it away. Sometimes the discoloration is deeply embedded in the nail plate, so don’t be disappointed if you can only make the stain lighter. Don’t dig at the color or keep filing, as you may cause permanent damage to the nail plate. The color will grow out with the nail in three to six months, depending on how close to the matrix it is and how fast the nails grow. Once you correct the wetness problem and eliminate the causes of any primary infections, you can safely reapply product and cover the discoloration with the client’s favorite shade of nail polish.

Orville J. Stone, M.D., is a dermatologist practicing in Huntington Beach, California. He has practiced dermatology and taught at medical schools for 30 years. He has published 150 scientific papers; the first paper on nail disorders appeared in 1962. He is well recognized for his expertise on nails and his extensive collection of nail disease photographs.