Linear verrucous epidermal nevus

Linear verrucous epidermal nevus (LVEN) is a rare skin condition characterized by the presence of well-demarcated, linear, verrucous (wart-like) plaques that follow the lines of Blaschko. These lesions are benign but can be associated with significant cosmetic concerns and, in some cases, other systemic manifestations. The condition is congenital, meaning it is present at birth, but may not become apparent until later in childhood or even adulthood.

Etiology and Pathogenesis

The exact cause of linear verrucous epidermal nevus is not fully understood. It is believed to result from somatic mutations that occur during embryonic development, leading to mosaicism. These mutations affect the normal development of the epidermis, resulting in the characteristic lesions. Unlike other forms of epidermal nevus syndrome, LVEN is not typically associated with systemic abnormalities.

Clinical Features

Linear verrucous epidermal nevus typically presents as skin-colored to brown, verrucous (wart-like), linear plaques. These plaques strictly follow the lines of Blaschko, which are invisible lines on the skin representing pathways of embryonic cell migration. The lesions can vary in size and thickness and are most commonly found on the trunk and extremities. Although LVEN is usually asymptomatic, lesions can become irritated or infected, leading to discomfort.

Diagnosis

The diagnosis of linear verrucous epidermal nevus is primarily clinical, based on the characteristic appearance and distribution of the lesions. In uncertain cases, a skin biopsy may be performed to confirm the diagnosis. Histologically, LVEN shows hyperkeratosis, papillomatosis, and acanthosis, which are typical features of verrucous epidermal nevi.

Treatment

There is no cure for linear verrucous epidermal nevus, and treatment is aimed at managing symptoms and improving cosmetic appearance. Options include topical treatments, such as retinoids and keratolytics, and procedural interventions like laser therapy, cryotherapy, and surgical excision. The choice of treatment depends on the extent and location of the lesions, as well as the patient's preferences and tolerance for potential side effects.

Prognosis

The prognosis for individuals with linear verrucous epidermal nevus is generally good, as the condition is benign. However, the cosmetic appearance of the lesions can be a significant concern for affected individuals, potentially leading to psychological distress. Regular follow-up with a dermatologist is recommended to monitor for any changes in the lesions and to manage any associated symptoms.

See Also

• Epidermal nevus syndrome
• Blaschko's lines
• Skin biopsy