wart

Warts are benign skin growths caused by infection with certain human papillomavirus (HPV) types that invade the keratinocytes of the epidermis. Most infections are mild or asymptomatic, and warts commonly resolve on their own over months to years, especially in children. Warts are contagious and can spread by direct skin contact or contact with contaminated surfaces or objects; autoinoculation can transfer the virus from one part of the body to another.

There are several main types of cutaneous warts. Common warts (verruca vulgaris) usually appear on the hands or fingers as rough, grainy bumps with a sometimes raised, cauliflower-like surface. Plantar warts (verruca plantaris) occur on the soles of the feet and may cause tenderness or a feeling of a lump or pebble under the foot. Flat warts (verruca plana) are smoother, smaller lesions that can appear in clusters on the face, neck, arms, or legs. Other forms, such as periungual or filiform warts, affect areas around nails or the face and mouth.

Diagnosis is generally clinical, based on appearance and location. In uncertain cases, a clinician may use dermoscopy or, rarely, a biopsy to distinguish warts from other skin conditions.

Treatment is not always necessary, given the potential for spontaneous clearance. When treatment is pursued, options include topical salicylic acid preparations, cryotherapy with liquid nitrogen, cantharidin, curettage or electrosurgery, and laser therapy. Some patients try duct tape therapy, though evidence is mixed. Recurrent warts can be challenging and may require a combination of approaches or referral to a specialist. Prevention focuses on reducing transmission through good hand and foot hygiene and protective footwear in shared areas; there is no vaccine for cutaneous warts.