Verrucae

Verrucae are common, benign skin lesions caused by infection with human papillomavirus (HPV). They arise when HPV infects keratinocytes in the epidermis, leading to hyperkeratotic, papillomatous nodules with a rough surface. More than 100 HPV types exist; certain types are linked to verrucae. Types 1, 2, 4, and 7 commonly cause cutaneous warts on the hands, fingers, and feet; plantar warts (verruca plantaris) tend to occur on weight-bearing areas of the soles and can be painful. Flat warts (verruca plana) are smoother and smaller and often appear in large numbers on the face or limbs. Genital warts are caused by HPV types 6 and 11 and are not usually classified with cutaneous verrucae.

Transmission occurs through direct skin-to-skin contact or contact with contaminated surfaces; autoinoculation can spread warts from one part of the body to another. They are common in children and adolescents and may be more persistent in adults with compromised immunity.

Diagnosis is usually clinical; dermoscopy can support the diagnosis, and biopsy is reserved for uncertain lesions or suspected malignancy.

Management: Because many verrucae resolve spontaneously, treatment is not always necessary. When therapy is desired or needed for symptoms, options include salicylic acid preparations applied to the lesion, often with occlusion; cryotherapy using liquid nitrogen; cantharidin; curettage or electrosurgery; laser therapy; and immunotherapy such as topical or intralesional imiquimod or antigen injections. Treatment responses vary, and recurrences are common, especially in children. For plantar warts, padding and protective footwear may help; avoid walking barefoot in public showers to reduce transmission.

Prevention: Avoid sharing towels or footwear, wash hands after touching warts, and maintain good skin health. HPV vaccines do not specifically target all verrucae-causing HPV types; they primarily prevent diseases associated with certain HPV types and do not guarantee protection against all cutaneous verrucae.