Plantar warts are abnormal skin growths that appear on the soles of the feet. These frequently appear over pressure bearing surfaces of the feet. They are caused by the virus, Human Papilloma Virus (HPV), which enters the skin through cuts or injuries on the feet. These warts are contagious and can spread through direct contact between individuals and also in the same individual from one location to another.
Plantar warts occur more frequently among children and teenagers. A weakened immune system also plays a role. In addition, the virus grows well in warm and humid conditions and therefore is more likely to be acquired from places like swimming pools and locker rooms.
Symptoms of Plantar Warts
- Fleshy growths over the soles of the feet which are generally small and present on the heels or base of the toes.
- Black spot may cover the warts, referred to as wart seeds
- Calluses may form over the wart when it has grown into the skin
- Pain and tenderness over the site of the wart when standing or walking
Diagnosis of Plantar Warts
The diagnosis is apparent on clinical examination of the lesion. Occasionally, a biopsy may be needed to confirm the diagnosis
Treatment of Plantar Warts
Occasionally, the warts may resolve on their own, especially in children. Treatment of the warts is recommended in case of pain and if the individual desires removal for cosmetic reasons in a persistent wart. The following treatment options are available which all involve destruction of the wart tissue through chemical or physical means.
- Salicylic acid: this helps to slowly peel away layers of the wart over time.
- Cantharidin: This is a chemical that forms a blister under the wart allowing for easy clipping of the wart by a dermatologist.
- Cryotherapy: This is a procedure which freezes the wart using liquid nitrogen, which helps it to fall off easily in a few weeks.
- Immunotherapy and chemotherapy: Some medications like imiquimod and 5-fluorouracil or bleomycin applied over the wart causes it to breakdown and helps the immune system fight the wart.
- Chemicals like trichloroacetic acid which are applied repeatedly over the wart to destroy the wart over time
- Surgical removal by excision or electric removal
- Laser therapy: This involves exposing the wart to repeated pulsed lasers which cut down the blood supply to the area leading to eventual sloughing of the wart
Prognosis of Plantar Warts
After treatment or removal of a wart, it is not uncommon for a new wart to develop in the same or different site. This occurs because the virus is difficult to completely remove from the site. The best way to prevent recurrence is to treat a wart as quickly as possible.
- Warts | American Academy of Dermatology [Internet]. [cited 2018 Jun 14]. Available from: https://www.aad.org/public/diseases/contagious-skin-diseases/warts#treatment
- Goldstein BG, et al. Cutaneous warts.http://www.uptodate.com/home. Accessed June 14, 2018.