Warts

Definition
Warts are benign (noncancerous) skin growths.

Causes/associated factors
Warts are caused by a virus called the human papillomavirus (HPV). There are more than 60 types of HPV, but only a few of them cause warts. The warts may last for weeks, years or even a lifetime, but often go away on their own without treatment. Warts typically appear on the hands, fingers and face. Although they may appear at any age, they're most common in children and young adults.
There are various types of warts. The common wart (verruca vulgaris) usually appears on the hands. The plantar wart (verruca plantaris), also known as the foot wart, develops on the sole of the foot. The flat wart (verruca plana) is often seen on the face and the back of the hands.


Transmission
The papillomavirus often enters the body through small breaks in the skin after direct contact with an infected person or through a process called autoinoculation, in which an existing wart spreads the virus to other parts of your body. Warts can also spread through contact with any object contaminated with living viral particles, such as the floors of public showers. The odds of developing warts depends on how often you're exposed to the virus, your immune system and your skin's vulnerability.
Although warts are contagious, they're not easy to catch. You may face a higher risk of developing warts if you:

go barefoot in public showers
experience trauma to the skin
have a weak immune system

Signs/symptoms
Warts may develop alone or in clusters. They often start small and grow larger. Most warts have rough surfaces and clearly defined edges. They're generally the same color as your skin, but can be darker or sprinkled with dark flecks. Most warts are painless and don't itch. Plantar warts, however, tend to grow inward and can hurt quite a bit. These warts typically develop on the plantar surface (sole) of the foot. They often grow in single clusters that can be the size of a quarter or larger.

Diagnosis
Diagnosis is based on your symptoms, medical history and a physical exam. Lab tests are typically unnecessary to confirm the diagnosis.

Treatment
For most people with healthy immune systems, warts disappear within weeks to a few years without treatment. Early treatment is often recommended, however, to help limit the spread of warts to surrounding skin or other people, as well as decrease the risk of complications.
Because there is currently no permanent cure for the virus, treatment aims to destroy the outer layer of skin where the wart grows or cause immune reactions in the affected area (a process known as immunotherapy, described below). At first, your doctor will probably suggest conservative treatment methods to minimize scarring and restore your skin to its usual pattern. The location, type and number of warts, as well as previous treatments and personal preferences, also affect treatment choices.

Over-the-counter treatments
Some warts may be removed with repeated applications of over-the-counter (OTC) preparations, such as salicylic acid, a keratolytic (medication that causes the skin to shed). Because these medications can damage normal skin, they should only be applied to the wart itself. Daily applications may be needed for up to 12 weeks. If you have a plantar wart, wearing an adhesive pad with a hole in the center over the wart can help eliminate pain when you walk.

Remember to consult your doctor before trying an OTC remedy, especially if you have diabetes or impaired circulation. When using the medication, follow the label instructions carefully.

Cryotherapy
Some warts can be removed with cryotherapy (freezing the tissue). To eliminate the wart completely, the treatment may need to be repeated within one to three weeks. The treatment may be painful. Rarely, permanent discoloration of the skin, scarring or nerve damage may occur.

Electrosurgery
With electrosurgery, the doctor uses an electric current to remove the wart. A single treatment may be all that's needed, but it may lead to scarring.

Laser therapy
Laser therapy may be used to dissolve certain warts. You may need local anesthesia, however. The plume that results with the use of the laser may cause the virus to spread, so the doctor will decide when this therapy is appropriate. Cost may also be a factor when deciding to use this treatment.

Bleomycin
Bleomycin is a cancer drug that can be injected into wart tissue. Bleomycin is very effective, but you may need local anesthesia. It should not be used on the fingers or toes due to possible nail loss or impaired circulation.

Surgery
For most warts, surgical removal is not typically recommended. Surgery may be used for very large warts that have not responded to other treatments, however. Surgery poses an increased risk of scarring, and the warts may return.

Immunotherapy
Immunotherapy can help boost the immune system by causing mild allergic reactions around the wart area. With a stronger immune system, you may be able to effectively fight off the virus causing the wart. Dinitrochlorobenzene (DNCB) is one medication in this category that's useful for stubborn warts.

Duct tape
A recent study showed that treating warts with duct tape was more successful for children than treating warts with cryotherapy using liquid nitrogen. Duct tape is placed over the wart for six days, then removed. Next, the area is soaked in water and rubbed with a pumice stone or emery board. After 12 hours, a new piece of duct tape is placed over the wart, and the cycle is repeated for two months or until the wart disappears. It's important to note that this small study involved only healthy children and that a doctor first identified the lesion as a wart before recommending duct tape therapy.


When to call the doctor
Contact your doctor if you have any questions or concerns about warts, or if:
warts develop on your feet, genitals or face
you suspect a wart is infected
a new wart develops after two weeks of treatment
warts still exist after 12 weeks of treatment

Complications
Warts may spread to other parts of your body, cause secondary infections or recur after treatment.

Pregnancy-specific information
If you develop a wart while you're pregnant, discuss the safety of any medications (including those available over the counter) with your doctor before beginning treatment.

Senior-specific information
With age, the immune system usually becomes less effective. You may become more vulnerable to infections, including warts. You may notice stronger or more frequent adverse effects of medication. If you develop warts, remember to tell your doctor about any medications you're taking or other health conditions you may have.

Prevention
Avoid touching another person's warts or wearing anyone else's shoes. Keep your feet clean and dry, and wear proper footwear when using public locker rooms or showers. Avoid using towels that have been used by a person who has warts. Finally, avoid skin trauma by protecting your skin and practicing good hygiene.
To prevent warts from spreading, avoid scratching any warts you may have and keep them covered while they're being treated. To help prevent spreading warts to others, cover any warts with a waterproof bandage while you're swimming or engaging in contact sports.