Abstract

Plasma cell mucositis is an infrequent condition of unknown etiology, which is characterized by intensely erythematous and edematous lesions of lobulated surface; it may affect the lips, but buccal mucosa, tongue, epiglottis, larynx and genital mucosae may also be affected. Histologically, this disorder shows a dense inflammatory infiltrate composed of plasma cells. We report two cases, the first a 50 year-old woman with a 2-year history of two erythematous lesions located on upper lip mucosa. Topical steroid therapy resulted in resolution of the lesions; however, the patient was lost to follow-up. Case two was a 47-year-old woman with similar lesions located in the upper labial mucosa and vestibular anterior gingiva. Histopathological analysis in both cases disclosed a dense plasma cell inflammatory infiltrate. Immunohistochemical analysis of case two showed positivity for both kappa and lambda chains. In this article we discuss the salient clinico-pathological features of this condition, as well as its treatment and differential diagnosis.