What are plantar warts? |

Definition

Plantar warts are growths on the soles of the feet. They are often mistaken for
corns or
calluses. The warts are different because they are caused by
a virus. Warts grow in clusters and are usually flat. A plantar wart can often be
distinguished by numerous black dots visible on its surface.

Although plantar warts are generally harmless, their location beneath the feet can make them tender. They also have a tendency to spread locally to other sites on the foot and elsewhere on the body.

Causes

Plantar warts, which are caused by the human papillomavirus (HPV), can be contracted by walking
barefoot on unsanitary surfaces. Touching and scratching can cause the virus to
spread.

Risk Factors

Factors that increase the chance for plantar warts include exposing one’s feet
to unsanitary surfaces. Plantar warts are more common in children and teens and in
persons with atopic dermatitis (eczema) or with a suppressed immune
system caused by AIDS, lymphoma, or the use of immunosuppressive drugs.

Symptoms

Symptoms of plantar warts are hard, flat growths on the soles of the feet;
heaped-up calluses surrounding the wart surfaces; and pain in the area of the
warts.

Screening and Diagnosis

A doctor will ask about symptoms and medical history and will examine the patient’s feet. Some doctors may wish to refer difficult cases to a specialist, such as a podiatrist, whose focus is on foot disorders, or a dermatologist, whose focus is on skin disorders.

Treatment and Therapy

There are many over-the-counter products available to treat warts. These therapies often contain a mild acid and can usually be applied when a wart first appears. Another popular and less expensive treatment is using duct tape to cover a wart for one week at a time. This is also done with weekly “sanding” of the wart with a pumice stone. A person should see a doctor if experiencing recurrent warts, if initial treatment fails, if over-the-counter therapies are not well-tolerated, and when the diagnosis is unclear.

After confirming the diagnosis of plantar warts, the doctor may use one or more
of the following treatments: cryotherapy (freezing the warts to kill
the virus), laser treatment (using a laser to kill the virus and destroy wart
tissue), electrocautery treatment (burning the wart), surgical removal (cutting
out the wart, with the patient under anesthetic), and immune therapy (application
of substances that stimulate the immune system’s response to the wart-causing virus).

Prevention and Outcomes

The best way to prevent plantar warts is to keep one’s feet from coming into contact with the virus that causes the warts. The following preventive measures are recommended: Avoid walking barefoot, except on sandy beaches; wear plastic sandals when showering in public bathrooms; change shoes and socks daily, and keep feet clean and dry; avoid direct contact with warts (of others or of one’s own body). In addition, periodically checking for warts on children’s feet may help prevent the warts from becoming larger and painful.

Bibliography

Al-Gurairi, F. T., M. al-Waiz, and K. E. Sharquie. “Oral Zinc Sulphate in the Treatment of Recalcitrant Viral Warts: Randomized Placebo-Controlled Clinical Trial.” British Journal of Dermatology 146 (2002): 423-431.

Alexander, Ivy L., ed. Podiatry Sourcebook. 2d rev. ed. Detroit, Mich.: Omnigraphics, 2007.

Brodell, Robert T., and Sandra Marchese Johnson, eds. Warts: Diagnosis and Management. Washington, D.C.: Taylor & Francis, 2003.

Lorimer, Donald L., et al., eds. Neale’s Disorders of the Foot. 7th ed. New York: Churchill Livingstone/Elsevier, 2006.

McCance, Dennis J., ed. Human Papilloma Viruses. New York: Elsevier Science, 2002.

Weedon, David. Skin Pathology. 3d ed. New York: Churchill Livingstone/Elsevier, 2010.