White Sponge Nevus of the oral mucosa – Case report

Abstract

White sponge nevus (WSN) is a rare autosomal-dominant disorder of the non-keratinized mucosa, characterized by a thickened white edematous mucosa whose surface appears irregular, wrinkly, or spongy. It affects mainly the oral mucosa. The histopathological examination demonstrates hyperparakeratosis, acanthosis with intracellular edema and vacuolization over the prickle cell layer, and eosinophilic perinuclear condensation. The currently accepted etiology is a mutation of the keratin 4 and/or keratin 13 genes. We present a case of WSN diagnosed in a 30-year-old white male patient with white corrugated bilateral lesions on the buccal mucosa that extended beyond the occlusal plane. A biopsy was obtained, and the histological presentation included superficial parakeratosis, prominent acanthosis of the squamous epithelium, and areas with prominent intracellular edema, which confirmed the diagnosis. No treatment was necessary other than patient counseling and initial 6-month follow-up consultation. His attending dentist was informed of the diagnosis, and further follow-ups were recommended.