A Case of Milia En Plaque Resembling Nevus Comedonicus

Nevus comedonicus and milia en plaque are two rare conditions that can occur in children. While nevus comedonicus manifests as grouped dilated and plugged follicular ostia organized in a honeycomb pattern especially on the face; milia en plaques manifests as multiple yellow-white cysts grouped on an erythematous edematous preauricular or retroauricular plaque. Dermoscopy helps with the diagnosis of either entity. In nevus comedonicus, it shows homogeneous circular or oval light or dark brown areas with prominent follicular plugs and typically uninvolved interfollicular skin; while in milia en plaque it shows multiples yellowish-white cysts with peripheral whitish halo, sparse pigmentation and multiple telangiectatic vessels. Histopathology shows follicular ostia filled with keratin in nevus comedonicus, and epidermal or dermal cysts surrounded by a mild to dense inflammatory infiltrate in milia en plaque. Our case was an 8 year-old girl who presented with milia en plaque that could be confused clinically with nevus comedonicus but was characteristic dermoscopically and in histopathology.