Podiatrist Tips

Plantar warts … a viral infection!

This plantar wart, which looks like cauliflower under the foot, is a plantar wart. The plantar wart is a viral infection that belongs to the human papillomavirus (HPV) family. It appears on the surface of the skin, which we call the epidermis. This often benign lesion thickens the epidermis layer, forming small rough bumps with sometimes the presence of blackheads which are actually small vessels perceptible to the naked eye. The most common form of the plantar wart under the foot is the vulgar wart. It can also infect other areas of the skin such as the knees, elbows, etc.

Are plantar warts carcinogenic?

Malignant plantar warts are uncommon. However, it is possible for a benign plantar wart to become carcinogenic. We see this, especially when the immune system is down. It is recommended that you consult your podiatrist or a dermatologist to eliminate the risk of skin cancer with the appropriate treatments.

What are the symptoms and signs of a plantar wart?

The signs and symptoms of a plantar wart are as follows:

It is possible to feel pain when you pinch the lesion. When the plantar wart is larger, it can be painful when walking. Patients may feel a sensation of a nail or a small bump that is uncomfortable or painful. Be careful! This pain may affect the way you walk and cause other pain.
The wart is contagious, so it can multiply on itself, creating a mosaic-like wart. In addition, it can infect others as well.
A plantar wart is usually located on pressure point or bony areas, such as the heel and sole of the foot. This is due to the possibility of an opening in the skin that allows the virus to enter.

What are the risk factors for contamination?

Walking barefoot in public places (swimming pool, hotel, etc.)
Dermatitis of the skin (exfoliated skin) or skin lesions caused by trauma or dryness of the skin (cracks or crevices)
Excessive perspiration of the feet causes the pores to open and allows the virus to infiltrate.
Weakening of the immune system. This can be caused by a disease (cancer, HIV infection, etc.) or by drugs (including immunosuppressants). In addition, warts in these people are often more difficult to treat.

How to treat plantar wart?

It is possible that our immune system is fighting alone the plantar wart virus, but sometimes it goes unnoticed. In this case, the inoculation of the virus settles in the epidermis of the skin and can often require treatment to prevent multiplication or contagion.

It is possible to start with salicylic acid in a pharmacy, but often the treatment is not strong enough to eliminate the lesion. Therefore, the podiatrist may prescribe a higher concentration of salicylic acid for either higher risk patients such as diabetics or patients with poor circulation. This is to reduce the risk of wounds and infection. In the paediatric population, this may also be an alternative.

There are more effective pharmacological treatments, but these must be administered by the podiatrist, such as cantharone. Cantharone is a drug that creates phlyctene, allowing more aggressive peeling of the superficial layers of the skin. This treatment can be painful and can become infected if the patient does not follow the podiatrist’s instructions.

There is a second pharmacological treatment that podiatrists use for recalcitrant or more difficult to treat plantar warts called bleomycin. Bleomycin sulfate is administered by intradermal injection. We avoid this procedure in children under 12 years of age.

There are invasive measures such as laser or surgical excision. This measure is rather rare, as pharmaceutical treatments are very effective. On the other side, in cases of stubborn plantar warts minor surgery or laser is an option, but unfortunately painful for a few days to weeks.

Cryotherapy is a treatment that is not very effective on the plantar surface of the feet. Liquid nitrogen cooled to -196 degrees causes a superficial burn of the epidermis that gradually eliminates the virus. However, the epidermis of the plantar surface is very thick so it does not penetrate deeply to destroy the virus. This treatment is painful and must be administered several times. Despite several treatments and the passage of time, the wart becomes more virulent. It can become mosaic or multiple, indicating the need to change treatments.

When to consult your podiatrist? When :

pharmaceutical treatments are not effective
the wart is painful or if it multiplies
there is bleeding, redness or signs of infection
the wart is abnormal or asymmetrical in shape
it deforms the nail
you have diabetes or peripheral sensation disorder (neuropathy)

For more information, don’t hesitate to consult your podiatrists at the Clinique Pied Outaouais.