Overview
What are warts?
Warts develop when HPV infects the outer layer of the skin, often entering through small cuts or abrasions. This triggers an overproduction of skin cells, forming lumps or lesions. Warts vary in size, shape, and texture depending on the type and location. Common types include:
- Common warts: Rough, raised bumps often found on hands, fingers, or knees. They may feature tiny black dots, which are clotted capillaries.
- Plantar warts: Hard, grainy growths on the soles of the feet. These can be painful when standing or walking.
- Flat warts: Small, smooth, flat-topped lesions that usually appear in clusters on the face, arms, or legs.
- Filiform warts: Thin, finger-like projections, commonly around the mouth, eyes, or nose.
- Genital warts: Flesh-coloured or grey growths in the genital or anal areas, often appearing in clusters.
Warts are usually harmless, though they can be uncomfortable or cosmetically concerning, and certain types (like genital warts) can spread more easily.
Symptoms and Causes
How warts appear and develop
Warts typically present as lumps or lesions that vary in appearance depending on their type and location. Features can include:
- Raised, rough bumps (common warts)
- Hard, painful growths on pressure points (plantar warts)
- Small, smooth lesions in clusters (flat warts)
- Finger-like projections (filiform warts)
What causes warts?
Warts are caused by HPV, which enters the skin through small breaks or abrasions. The virus accelerates skin cell growth, forming visible lumps. Factors that increase the risk of developing warts include:
- Direct contact: Touching someone else’s wart or surfaces contaminated with the virus.
- Weakened immune system: Illness, certain medications, or age-related changes that reduce immune defences.
- Skin trauma: Nail-biting, picking at hangnails, or minor injuries.
- Shared public spaces: Environments such as swimming pools, showers, and gyms can facilitate viral spread.
Diagnosis and Tests
Most warts can be diagnosed through a visual examination by a GP or dermatologist. The clinician considers size, shape, texture, and location. Usually, no further tests are necessary.
When a dermatologist is needed
Referral to a specialist may be required if:
- Warts are persistent, widespread, or resistant to standard treatments
- The diagnosis is uncertain
- Warts appear on sensitive areas such as the face, nails, or genitals
- Specialist procedures like cryotherapy or laser therapy are being considered
Additional tests
In certain cases, further investigations may be performed:
- Skin biopsy: A small tissue sample is taken to confirm diagnosis if unusual warts are present
- HPV testing: Swabs can detect the specific virus type, particularly for genital warts
- Acetic acid test: A vinegar solution temporarily whitens genital warts, aiding visual identification
Management and Treatment
Warts often resolve without treatment over time, but professional care can accelerate healing, reduce discomfort, and prevent spreading. Treatment depends on the type, size, location, and patient preference.
Over-the-counter and at-home treatments
These treatments can be effective for mild warts or when professional care is not immediately available:
- Salicylic acid: Applied directly to the wart to gradually dissolve the tissue. Requires daily application over several weeks.
- Cryotherapy kits: Home freezing treatments can reduce wart size, though professional cryotherapy is stronger and more precise.
Medical treatments
Professional care is recommended for persistent, painful, or large warts:
- Cryotherapy: Freezing the wart with liquid nitrogen, typically in a clinic. Multiple sessions may be needed.
- Electrosurgery and curettage: Burning or scraping off the wart. Often used for larger or stubborn warts.
- Laser therapy: Focused light targets and destroys wart tissue; effective for resistant cases.
- Chemical treatments: Strong acids or prescription topical medicines applied by a clinician.
- Immunotherapy: Stimulates the immune system to fight HPV and help clear warts.
Outlook/Prognosis
Most warts are harmless and may disappear naturally over months or years. Professional treatments often accelerate resolution and reduce discomfort, though recurrence is possible, particularly in individuals with weakened immune systems. Persistent or painful warts respond well to interventions like cryotherapy, laser therapy, or immunotherapy.
Prevention
While it is impossible to prevent all warts, these strategies can reduce the risk of infection and recurrence:
- Avoid direct contact with warts on others or contaminated surfaces.
- Maintain healthy, intact skin and moisturise regularly.
- Wear footwear in public pools, showers, and locker rooms.
- Do not share personal items such as towels, razors, or socks.
- Strengthen your immune system with a balanced diet, exercise, and adequate sleep.
- Consider the HPV vaccine for protection against certain virus strains.
