Human Papillomavirus (HPV) is a family of over 200 related viruses. Cutaneous HPV describes a group that infects the skin’s surface, leading to common, non-cancerous growths known as warts. These infections are common, particularly among children, and are benign skin lesions.
Types and Symptoms of Cutaneous HPV
Cutaneous HPV can manifest as various types of warts, each with distinct appearances and preferred locations. Common warts, also known as verruca vulgaris, appear as rough, raised bumps with a grainy texture. They are often found on fingers, hands, elbows, and knees and may contain small black dots, which are clotted blood vessels. These warts can range in size from tiny pinheads to larger, pea-sized growths.
Plantar warts develop on the soles of the feet, often in pressure-bearing areas like the heels or balls of the feet. They tend to grow inward due to the pressure from walking, creating a thick, calloused appearance with tiny black dots. This inward growth can cause discomfort or pain, feeling like a pebble stuck in one’s shoe.
Flat warts, or verruca plana, are small, smooth, and slightly raised, often appearing in clusters of 20 to 200. They are commonly found on the face, arms, and legs and can be flesh-colored, pink, light brown, or slightly yellow. Filiform warts present as long, thin, finger-like projections, usually appearing on the face, especially around the eyelids, mouth, or nose.
How Cutaneous HPV Spreads
Cutaneous HPV primarily spreads through direct skin-to-skin contact with an infected person or by touching contaminated surfaces. This includes walking barefoot in public areas like locker rooms or around swimming pools, where the virus thrives in warm, moist environments. Sharing personal items like towels, razors, or nail clippers can also facilitate transmission.
The virus enters the body through small breaks in the skin, such as cuts, scrapes, or tiny abrasions from nail-biting or cuticle chewing. A weakened immune system can increase susceptibility to developing warts after exposure. Auto-inoculation, the spread of warts from one part of a person’s body to another, is also common.
Treatment Approaches for Cutaneous HPV
Various treatment options are available for cutaneous HPV, ranging from over-the-counter remedies to professional medical procedures. Over-the-counter treatments commonly involve products containing salicylic acid, available as liquids, gels, pads, or ointments. Salicylic acid works by gradually dissolving the abnormal skin cells of the wart. For effectiveness, the wart should be soaked in water before application, and dead skin cells gently removed.
Another over-the-counter option is freezing sprays, which typically contain liquid butane, dimethyl ether, or propane. These sprays freeze the wart tissue, causing it to blister and eventually fall off. Home freezing kits may not reach the low temperatures achieved by professional cryotherapy and might be less effective for larger or deeper warts.
Professional medical treatments include cryotherapy, where a healthcare provider uses liquid nitrogen to freeze the wart. Other procedures include electrocautery, which burns off the wart, and laser therapy, which destroys wart tissue with a focused light beam. Surgical excision involves cutting out the wart. Topical prescription medications like imiquimod or cantharidin may also be used. While some warts may resolve spontaneously, treatment can accelerate resolution and help prevent further spread.
Preventing Cutaneous HPV
Preventing the acquisition and spread of cutaneous HPV involves several practical measures. Avoid direct contact with existing warts on oneself or others. Refrain from sharing personal items such as towels, razors, or nail clippers, as these can harbor the virus.
Wearing protective footwear like flip-flops or pool shoes in communal wet areas, such as public showers, locker rooms, and swimming pool decks, can help prevent infection. Maintaining healthy, moisturized skin reduces the likelihood of cracks and abrasions, which serve as entry points for the virus. Avoiding picking at warts or biting nails and cuticles also prevents auto-inoculation.
Understanding the Difference Between Cutaneous and Genital HPV
It is important to distinguish between cutaneous HPV and genital HPV, as they have distinct implications. Cutaneous HPV types primarily infect the skin and cause common warts on areas like the hands, feet, and face. These types, such as HPV-1, -2, -3, -4, and -10, are benign and do not lead to cancer.
In contrast, genital HPV types primarily affect mucous membranes, particularly in the anogenital region and oropharynx, and are predominantly transmitted through sexual contact. Genital HPV is categorized into low-risk types, like HPV-6 and HPV-11, which commonly cause genital warts. High-risk genital HPV types, such as HPV-16 and HPV-18, are linked to various cancers, including cervical, anal, penile, vaginal, vulvar, and some head and neck cancers. Contracting cutaneous HPV does not mean one has or will develop genital HPV or associated cancers, as the strains causing skin warts are distinct from those linked to sexually transmitted infections and cancer.