Nevus Unius Lateris With Epidermolytic Hyperkeratosis Managed With Radiofrequency Ablation: A Case Report.

Nevus unius lateris is a rare, systematized clinical variant of verrucous epidermal nevus, characterized by extensive unilateral verrucous lesions following the lines of Blaschko. While most epidermal nevi are localized, the systematized form often raises concerns for epidermal nevus syndrome, which involves associated multisystem abnormalities in the skeletal, ocular, and neurological systems. We present the case of an 18-year-old male with extensive, hyperpigmented, verrucous plaques involving the left side of his trunk, upper limb, and lower limb without associated extracutaneous abnormalities. The lesions had been present since early childhood and showed significant progression following puberty. A comprehensive systemic evaluation, including orthopedic and ophthalmological consultations, revealed no associated internal anomalies. Histopathological examination of a biopsy specimen confirmed the diagnosis of a verrucous epidermal nevus with prominent epidermolytic hyperkeratosis. The patient was managed with multiple sessions of radiofrequency ablation for selected lesions, with satisfactory cosmetic and symptomatic improvement. This case underscores the importance of a thorough systemic workup in patients with extensive epidermal nevi and highlights the role of ablative therapies in managing the cutaneous manifestations of this rare condition.