Medical & Surgical Dermatology
What are warts?Warts are non-cancerous skin growths caused by a viral infection in the top layer of the skin. Viruses that cause warts are called human papillomavirus (HPV). Warts are usually skin-colored and feel rough to the touch, but they can be dark, flat and smooth. The appearance of a wart depends on where it is growing.
How many kinds of warts are there?There are several different kinds of warts including:
- Common warts
- Foot (Plantar) warts
- Flat warts
Common wartsusually grow on the fingers, around the nails and on the backs of the hands. They are more common where skin has been broken, for example where fingernails are bitten or hangnails picked. These are often called "seed" warts because the blood vessels to the wart produce black dots that look like seeds.
Foot wartsare usually on the soles (plantar area) of the feet and are called plantar warts. When plantar warts grow in clusters they are known as mosaic warts. Most plantar warts do not stick up above the surface like common warts because the pressure of walking flattens them and pushes them back into the skin. Like common warts, these warts may have black dots. Plantar warts have a bad reputation because they can be painful, feeling like a stone in the shoe.
Flat wartsare smaller and smoother than other warts. They tend to grow in large numbers - 20 to 100 at any one time. They can occur anywhere, but in children they are most common on the face. In adults they are often found in the beard area in men and on the legs in women. Irritation from shaving probably accounts for this.
How do you get warts?Warts are passed from person to person, sometimes indirectly. The time from the first contact to the time the warts have grown large enough to be seen is often several months. The risk of catching hand, foot, or flat warts from another person is small.
Why do some people get warts and others don't?Some people get warts depending on how often they are exposed to the virus. Wart viruses occur more easily if the skin has been damaged in some way, which explains the high frequency of warts in children who bite their nails or pick at hangnails. Some people are just more likely to catch the wart virus than are others, just as some people catch colds very easily. Patients with a weakened immune system also are more prone to a wart virus infection.
Do warts need to be treated?In children, warts can disappear without treatment over a period of several months to years. However, warts that are bothersome, painful, or rapidly multiplying should be treated. Warts in adults often do not disappear as easily or as quickly as they do in children.
How do dermatologists treat warts?Water’s Edge Dermatology practitioner's are trained to use a variety of treatments, depending on the age of the patient and the type of wart.
Common wartsCommon warts in young children can be treated at home by their parents on a daily basis by applying salicylic acid gel, solution or plaster. There is usually little discomfort but it can take many weeks of treatment to obtain favorable results. Treatment should be stopped at least temporarily if the wart becomes sore. Warts may also be treated by "painting" with cantharidin in the Water’s Edge Dermatology practitioner's office. Cantharidin causes a blister to form under the wart. The Water’s Edge Dermatology practitioner can then clip away the dead part of the wart in the blister roof in a week or so.
For adults and older children cryotherapy (freezing) is generally preferred. This treatment is not too painful and rarely results in scarring. However, repeat treatments at one to three week intervals are often necessary.
Electrosurgery (burning) is another good alternative treatment. Laser treatment can also be used for resistant warts that have not responded to other therapies.
Foot wartsFoot warts are difficult to treat because the bulk of the wart lies below the skin surface. Treatments include the use of salicylic acid plasters, applying other chemicals to the wart, or one of the surgical treatments including laser surgery, electrosurgery, or cutting. The Water’s Edge Dermatology practitioner may recommend a change in footwear to reduce pressure on the wart and ways to keep the foot dry since moisture tends to allow warts to spread.
Flat wartsFlat warts are often too numerous to treat with methods mentioned above. As a result, "peeling" methods using daily applications of salicylic acid, tretinoin, glycolic acid or other surface peeling preparations are often recommended. For some adults, periodic office treatments for surgical treatments are sometimes necessary.
What are some of the other treatments for warts?There are several different lasers used for the treatment of warts. Laser therapy is used to destroy some types of warts. Lasers are more expensive and require the injection of a local anesthesia to numb the area treated.
Another treatment is to inject each wart with an anti-cancer drug called bleomycin. The injections may be painful and can have other side effects.
Immunotherapy, which attempts to use the body's own rejection system is another method of treatment. Several methods of immunotherapy are being used. With one method the patient is made allergic to a certain chemical which is then painted on the wart. A mild allergic reaction occurs around the treated warts, and may result in the disappearance of the warts.
Warts may also be injected with interferon, a treatment to boost the immune reaction and cause rejection of the wart.