Epidermolytic palmoplantar keratoderma

Epidermolytic palmoplantar keratoderma (EPPK), also known as Vörner palmoplantar keratoderma or keratosis palmoplantaris cum degeneratione granulosa, is a hereditary skin disorder characterized by diffuse, thick, yellow hyperkeratosis (thickening of the skin) affecting the palms of the hands and soles of the feet. It is the most common form of diffuse palmoplantar keratoderma. Symptoms typically appear in the first months of life, with well-demarcated thickening of the skin on the palms and soles that may be accompanied by a red border at the margins. The thickened skin can develop painful fissures (cracks), and hyperhidrosis (excessive sweating) of the affected areas is common, which may lead to secondary bacterial or fungal infections and associated malodor. Histologically, the condition is distinguished by epidermolytic hyperkeratosis, a characteristic pattern of degeneration in the upper layers of the epidermis. EPPK is caused by mutations in the KRT9 gene (keratin 9), which encodes a keratin protein expressed specifically in the suprabasal epidermis of palms and soles. Less commonly, mutations in KRT1 (keratin 1) have been associated with this condition, sometimes with mild involvement of skin beyond the palms and soles. The disease follows an autosomal dominant inheritance pattern, meaning a single copy of the altered gene is sufficient to cause the disorder. There is currently no cure for epidermolytic palmoplantar keratoderma. Treatment is symptomatic and focuses on managing the thickened skin. Topical keratolytic agents such as salicylic acid, urea-based creams, and topical retinoids are commonly used to soften and reduce the hyperkeratosis. Mechanical debridement (careful removal of thickened skin) may also be helpful. Oral retinoids such as acitretin may be considered in more severe cases but require careful monitoring due to potential side effects. Management of hyperhidrosis and prevention of secondary infections are also important aspects of care. Regular follow-up with a dermatologist experienced in genodermatoses is recommended.

Common questions about Epidermolytic palmoplantar keratoderma