Plantar warts are a very common non-malignant (not caner) skin condition found on the feet. These skin lesions are caused by various types of human papillomaviruses (HPV). The formation of plantar warts begins when the HPV enters cuts or cracks on the bottom of the foot. Plantar warts commonly appear on areas of increased pressure such as the heel or ball of the foot. If the plantar wart is found on an area of high pressure, the wart becomes thickened. It then grows into the foot and can become painful with walking and running. Another characteristic of plantar warts is they usually form in small clusters called satellite warts that radiate from a larger plantar wart.
Physical Exam of Plantar Warts:
Plantar warts can be confused with skin melanomas (cancer), which can be harmful and/or life-threatening if the cancer cells spread. They may also be confused with calluses, which form due to increased pressure to the feet. The skin lesion will be examined for presence of skin lines and color. If the skin lesion is thickened and multicolor, skin melanomas are suspected and a skin biopsy is performed to confirm the finding. In contrast to skin melanomas, plantar warts usually appear uniform in color. When comparing plantar warts to calluses, plantar warts do not have skin lines and will bleed if the area is shaved down with a scalpel. Additionally, patients with plantar warts will show signs of pain if the wart is squeezed as opposed to direct pressure applied to the top. Treatment of Plantar Warts: Plantar warts can be very difficult to treat because certain treatments affect each type of human papillomaviruses differently. To add to the difficult treatment of plantar warts, HPV has become more resistant to current treatments. Fortunately, there are many options to treating plantar warts, starting from a more conservative, non-surgical care to surgical solutions of excising the skin lesion.
First line of treatment:
The first line of treatment of plantar warts is over-the-counter solutions, creams, or patches containing salicylic acid like Trans-Ver-Sal or Duofilm. The acid softens the thick hard skin so that a pumice stone or file can be used to rub off the plantar wart. The advantages of using an over-the-counter product are its low cost and minimal discomfort. The disadvantage of using the products is the duration of the treatment and its dangers to diabetics and/or patients with circulatory problems. The whole course of treatment usually requires a diligent and regular application for a minimum of 3 months.
Second line of treatment:
A second line of treatment is cryotherapy. The wart is frozen with chemicals until a 1-2 mm white halo surrounds the plantar wart. This procedure is performed at the podiatrist office every 2-3 weeks.
The next method of treatment in the second line is Cantharone compounds. Using this method, the podiatrist will first shave all of the excess callus tissue from the top of the wart. Next the Cantharone compound is applied, allowed to dry and then covered with a band-aid. When possible, pads will be applied around the treated area to off load pressure. Usually, there is no pain when the compound is applied. Within 3 to 7 hours the compound works into the skin and will begin to burn. After about 24 to 48 hours, a blister will form. As the blister forms this area can become quite painful. The blister is usually deeper than a common water blister and may appear white, yellow or dark in color. When the blister is forming, the patient is encouraged to soak the area. Once the blister is formed the patient should try to puncture the blister and release the fluid. During the first few days, and possibly as long as a week, the treated area can be painful and the patient should continue using a pad to keep pressure off of the blister.
Another second line treatment is a prescription cream, such as Aldara, containing the active ingredient, imiquimod or Carac cream containing the active ingredient, fluorouracil. The imiquimod in the Carac cream activates the body’s immune cells that fight bacteria, viruses and destroy the HPV cells. The precaution to Aldara cream is that pregnant women and children under the year of 12 years old should not use it. The duration of Aldara cream treatment is a maximum of 16 weeks. Creams with fluorouracil inhibit viral growth and stops the HPV in plantar warts from growing. The duration of this treatment is about 2 weeks. For both topical treatments, irritation, itchiness, and redness to the skin can occur.
The last therapy in the second level of wart treatment is injections of Candida antigen into the lesion. Approximately 0.3cc of the antigen is injected directly into the wart. This works by initiating a local allergic response. When the patient’s body reacts to the allergen, antibodies are sent to the area and will try to destroy the Candida particles. These same immune cells will also attack the wart tissue. This procedure is done in the doctor’s office every other week and could take up to seven treatments. The down side to this treatment is the patient may occasionally feel flu like symptoms the day after the procedure.
Third line of treatment:
The third line of treatment is the surgical removal of warts. This procedure is performed in the podiatrist office and requires local anesthetic injections to numb the foot.
A curette, a small spoon-like instrument, it is used to scoop out the infected tissues and scrape out the viral cells that are embedded in the skin. Finally, phenol (a powerful form of alcohol that burns tissue and stops bleeding) may be used to kill the viral particles from the plantar wart and decrease bleeding from the procedure.
The area is then covered with gauze and bandages. After this procedure is done the patient is required to decrease pressure on the foot to alleviate pain and allow the area is heal. After the surgical procedure, the patient will need to return to the podiatrist office in order to follow the effectiveness of the procedure and to evaluate the healing progress of the wound. The disadvantage to this treatment is there is a possibility a painful scar may form at the site of the surgery.
1. Avoid walking barefooted in public showers or swimming pools
2. Avoid sharing shoes and socks