What Are Flat Warts?

Warts are caused by the human papillomavirus (HPV). The infection causes roughness and skin-coloured bumps on the skin. The virus is contagious and you can get it just from touching other people's warts. There are different types of warts; these include common warts, flat warts, plantar warts, and genital warts.

Flat warts are smooth, small, benign (non-cancerous) bumps on the skin. These warts are flatter and smaller than other warts. They usually appear in groups and are commonly seen on hands and the face. They may be yellowish-brown, pink or skin coloured. They are about the size of a pinhead.

A flat wart does not usually cause pain. They usually don’t require treatment and will go away on their own, but it may take several months or years. The virus can enter through small breaks in the skin and can spread to other places of the body.                                  

Overview

Flat warts are smooth, small, benign bumps on the skin caused by the Human papillomavirus (HPV). They are smaller and flatter than other warts. They commonly appear on the face and hands, usually seen in groups. They are yellowish-brown, pink, or skin coloured. Flat warts don't cause any pain, they usually do not require any treatment but it may take months or years for them to disappear on their own.^1,3 

Causes of flat warts

Warts appear when the skin cell grows faster than normal because of the infection caused by the human papillomavirus (HPV).² There are more than 100 types of HPV strains, some of which are high-risk strains causing cancer, and others are non-cancerous strains.¹

We all come in contact with human papillomavirus (HPV) when we shake hands with people,  touch door knobs, or share towels. When the human papillomavirus (HPV) enters a cut in the skin, it causes infection and forms warts. Warts are contagious; this virus can spread from person to person or different parts of the body. HPV survives in warm, damp environments.

Certain HPV strains cause genital and anal warts. They are transmitted through sexual contact. Some strains may cause cellular changes in the cervix and can become cancerous. 

Signs and symptoms of flat warts

• Commonly seen on the face and back of the hand.
• It can be found on the legs, especially in women. 
• In the case of men, they are commonly seen in the beard area
• Flat warts are skin coloured - often yellow, brown or pink
• They are small, between 1-5mm, not bigger than the head of a pin
• It may appear round or oval-shaped and slightly raised.
• Mostly appear in groups or clusters

Management and treatment for flat warts

Warts usually disappear on their own; however, this process can take months or years. The treatment available is the removal of the warts, but they can reappear or sometimes spread due to the virus.^4.5 People with flat warts who are pregnant or breastfeeding or have severe diabetes are advised to consult the doctor before starting the treatment at home. Treatments offered are: 

Over-the-counter wart removers

• These medications contain salicylic acid, which can remove the warts. This can be applied straight to the wart.

• Before applying salicylic acid, the wart should be soaked in warm water.
• After soaking the wart, thick or loose skin may be seen on the wart, and it should be removed.
• Removal of the skin helps the medication to penetrate better and aids recovery.
• Repeat this process once or twice a day until the wart is gone.
• Consult the doctor if there is no improvement after doing this process and there is growth in the size of the warts.

Duct tape

• Low-risk and low-tech approach
• The wart is covered by duct tape before the salicylic acid is applied
• This is repeated until the wart disappears
• There is no scientific study on this method
• It is potentially a home remedy for flat warts

Cryotherapy

• During cryotherapy treatment, a dermatologist freezes a wart using liquid nitrogen.
• The extreme cold burns the skin, causing pain, redness, and usually blisters.
• Treatment takes 3 - 4 months to get rid of the warts

Imiquimod cream

• Imiquimod is a topical immunotherapy drug used for treating skin warts.

Cantharidin

• Cantharidin is a chemical to apply on warts, which causes blisters under warts and lifts them from the skin.

Electrocautery

• The dermatologist may use electrocautery in which an electric needle or laser is used to remove the warts.

Surgical removal

• The surgeon cuts or scrapes away the wart with the scalpel this process can cause scarring. 

Diagnosis

Diagnosis is carried out in two ways:

1. Physical examination: 

The consulting doctor carries out a physical examination assessing the appearance. Flat warts are diagnosed based on their appearance.

2. Skin biopsy: 

In this procedure (skin biopsy) a dermatologist takes a sample of affected skin and confirms the condition.⁶

Risk factors

Flat warts are caused by the Human papillomavirus (HPV) and are harmless. Warts can affect people of any age but commonly affect school children. People with HIV,  organ transplants or chemotherapy have higher chances of getting warts because of their weakened immune system. HPV can be transmitted through: 

• Skin-to-skin contact with someone with warts or HPV
• Skin-to-mucus contact with someone with warts or HPV
• Touching or using an object that has come in contact with an HPV person, such as towels, razors, furniture, doorknob etc.
• Sexual contact with a person with HPV 
• Open cuts on the skin
• Moist skin or environment
• Poor hygiene
• Having a weak immune system

FAQs

How can I prevent flat warts?

• Maintain proper hygiene
• Wash hands after touching warts
• Avoid skin contact with a person who has flat warts 
• Don’t share clothes, towels or personal items with other people
• Wear slippers while using public showers, locker rooms, etc.
• Keep hands clean and dry.
• Avoiding scratching the flat warts can prevent further spreading of the warts.

How common are flat warts?

Flat warts are caused by human papillomavirus (HPV). Warts can affect any age group but are most commonly seen between 12–16 years old.⁴ Mostly seen in school children rather than adults. People with a high risk of getting warts are those with HIV or organ transplants or on chemotherapy because of their weakened immune systems.

Are flat warts contagious?

Flat warts are caused by human papillomavirus (HPV). They are not highly contagious but can spread through skin-to-skin contact or a small cut in the skin. Warts can also spread from one part of the body to the other by touching or scratching the warts.

When should I see a doctor?

Flat warts should be examined by a healthcare professional to rule out skin cancer. If you are pregnant, breastfeeding or have chronic disease conditions like diabetes or HIV you should consult a doctor before taking any treatment for flat warts. Consult a doctor if: 

• Warts don't respond to treatment
• Redness, bleeding or pain in the warts
• Genital warts appear 
• Spreading or change in the appearance of the warts

Summary

Flat warts are caused by the human papillomavirus (HPV). They are not highly contagious but can spread through skin-to-skin contact with a person with HPV. Commonly, the warts do not cause any pain or irritation. Flat warts do not need any treatment as they disappear on their own as time passes but can take months or years.

Flat warts are confirmed through physical examinations and skin biopsies. The treatment is the removal of warts where there is a chance of recurrence, and in some cases, it can spread. Before starting a treatment, it is better to consult a healthcare professional if you are an immunocompromised person, pregnant or breastfeeding. Maintaining proper hygiene can help prevent the occurrence and spread of the warts.