Eosinophilic ulcer of the oral mucosa: report of a child with CD30-negative cells in an infiltration on the lower lip.

Background: Eosinophilic ulcer of the oral mucosa (EUOM), also known as traumatic eosinophilic granuloma or Rida-Fede disease, is an uncommon, benign and self-limited lesion of the oral mucous membrane. The tongue is the most common location of EUOM, accounting for up to 60% of the cases, with the lateral and dorsal surfaces being principally affected. EUOM clinically manifests as a painful, nodular inflammatory infiltration, usually with ulceration.