Nevus Comedonicus with Epidermolytic Hyperkeratosis: A Case Report.

Nevus comedonicus (NC) is a rare developmental anomaly of the folliculosebaceous apparatus, which appears as numerous dilated papules containing firm, darkly pigmented, horny plugs. It appears shortly after birth and mostly before the age of 10; however, late-onset cases have been reported. There is no gender or racial predilection. Moreover, NC can be a component of nevus comedonicus syndrome, a neurocutaneous disorder with skeletal, ocular, and central nervous system abnormalities. EHK properties in NC are not a common finding and are rarely seen in association with each other. This paper reports a healthy, 27-year-old young woman who has been developing numbers of asymptomatic unilateral linear skin lesions on her chest, waist, right thigh, and popliteal fossa in a unilateral linear pattern over ten years. Skin biopsy revealed dilated follicular ostia with orthokeratotic hyperkeratosis, columns of parakeratosis, cornoid flagellation, epidermolytic hyperkeratosis, and mild acanthosis on its wall.