Q: The white area at the free edge of one of my long standing client’s natural nails changed shape and started progressing into the nail bed. I shortened the nail and she tried an over-the-counter topical medication, but the white area kept spreading. Her doctor said it was bacteria that could become an infection. I’ve seen this before and found soaking the affected nails in white iodine helps . I’ve been told this condition occurs when people wash their pets or do gardening without wearing rubber gloves. I’ve also heard it can be caused by emotional stress.

A: I feel very positive that this white area is not caused by bacteria. The nail is an amazing structure, and a healthy nail is too hard and too dry for bacteria to invade. There must be an injury or wet pocket around the nail for bacteria to grow.

You could have used nail products that dried out the nail plate and caused it to fracture, but it’s more likely that the problem is caused by an injury to the nail matrix that is making the nail prone to fracturing. Once the nail fractures, air enters the area and causes it to appear white.

Since I do not believe bacteria is involved, I don’t think white iodine will do anything except give the client something to do while the nail grows out. As with many nail disorders, the cure is more often achieved by time than by iodine.

Clients with normal, healthy nails shouldn’t worry about washing pets or gardening unless they wear acrylics. However, rubber gloves are always a good idea to protect the nails from dirt and bacteria that can become lodged under the nail.

I do believe stress influences many disorders, but I feel it is blamed for too many health problems. Until someone finds a biological mechanism to explain it, I don’t go overboard in blaming stress. I usually say to the patient, “Everyone says this is due to nerves. I don’t know what causes it.”But it is impossible for emotional stress to cause changes within the dead cells of a nail.

Q: The nail on one of my client’s middle fingers twists as it grows. She writes with that hand and the pen rests on the side of her finger, near the nail. It isn’t painful, but my client is embarrassed by it because she feels it’s unattractive. What causes the twisting and is there anything that can be done to correct it?

A: I like to think of the nail as mouldable, just like plastic. If you put pressure on the nail matrix (the mold), you change the shape of the nail. This client is obviously putting pressure on the area where the nail forms. I commonly see calluses near the nail from writing pressure. Encourage her to hold her pencil with her fingertips so that it doesn’t put pressure on or near the matrix. She also could put protective padding on the nail. School supply stores sell a simple device that helps beginning writers hold pencils or pens. It may also help your client write without putting pressure on the nail matrix.

Q: I read your article on allergic reactions to formaldehyde (February 1992). I have a client who has an allergic reaction just like you described on her thumbnail. She hasn’t worn acrylics in four years and she’s had the reaction ever since she started coming to me. She saw a doctor who gave her pills and a topical ointment. Nothing helps. After reading your article I stopped using formaldehyde products on her. Two months later it spread to two more fingers. Can anything else be going on?

A: The fact that more lessons developed two months after stopping use of formaldehyde nail products suggests that the products have nothing to do with the disorder. Additionally, a true allergy would most likely occur on all 10 nails. Many different health problems can produce inflammation under the nail or separation of the nail. These include psoriasis or other skin diseases, thyroid or hormone problems, arthritis, or vascular disease. Your client should see a dermatologist to determine the cause of her condition.

In the meantime, you can cover her nails with nail polish to conceal the defects. Don’t use formaldehyde products or penetrating nail hardeners. Unless she is allergic to the product you’re using, it won’t harm anything, and the client will feel much better about how her nails look.

Q: My client has been wearing acrylic nails for a year and a half. A few of her nails had a tendency to curl upwards and the index finger gave us the most problems. After six months of wearing acrylics, the nail on her index finger began to thicken near the free edge. At times it was tender to pressure. Two weeks after her last fill, the finger became red and swollen and I referred her to a doctor. He called it a fungus and said she would lose the nail. He prescribed antibiotic, and when the redness and pain were gone I removed all the product. After a few weeks the nail became crumbly, like the keratin was breaking down. A new nail has grown out now, but it’s beginning to thicken again. What is causing this? Is it formaldehyde allergy and what can be done to prevent the whole process from happening again? Will it spread to other nails?

A: The thickening skin under the nail is a result of chemical irritation from acrylics. See my column called “Acrylic Nail Reactions” (August 1991). The nail’s blood supply can be damaged by trauma or an infection such as the one your client suffered. This damage interferes with the nutrition of the nail and nail bed and causes the skin to thicken. The damage usually corrects itself in a few months, but sometimes it can be permanent.

I feel confident that this was not fungus. I think there was probably a secondary bacterial infection and that is what the doctor treated. There is no antibiotic that kills both fungus and bacteria. I think he recognized the bacterial infection and treated it.

While waiting for the damage to correct itself, you can make your client feel better by gently filing down the crumbling and thickening and coating her nails with polish.