Introduction
Mucosal plasmacytosis is an uncommon, non-neoplastic condition characterised by an intense plasma cell proliferation in the affected tissue.
The aetiology and pathogenesis of this condition are often unknown. We present an unusual case of oropharyngeal mucosal plasmacytosis related to the use of toothpaste.
Case report
A healthy, 59-year-old Chinese man presented to the ENT out-patient clinic with a two-month history of persistent and progressive hoarse voice, which had failed to improve after two courses of oral antibiotics from his general medical practitioner.
In addition to his hoarseness, the patient had a dry, non-productive cough and subjective difficulty in swallowing solid food. There was no associated pain or other symptoms. The patient was a lifelong non-smoker and non-drinker.
Examination revealed a diffusely oedematous supraglottic area involving the epiglottis and both aryepiglottic and median glossoepiglottic folds. There was no surface ulceration (Figure 1).
Fig. 1 Endoscopic view of diffuse swelling involving the epiglottis and aryepiglottic and glossoepiglottic folds.
Haematological investigations were normal, including white cell count and erythrocyte sedimentation rate.
An initial clinical diagnosis of laryngopharyngeal reflux was made and treated with a proton pump inhibitor.
No changes were noted at a two-month review appointment, and oral fluconazole was prescribed to cover the possibility of laryngeal candidiasis.
A further review four weeks later showed no improvement. The patient therefore underwent an elective examination and biopsy under general anaesthesia. The biopsy showed florid inflammatory changes, including a dense, mixed inflammatory infiltrate involving the full thickness of the epithelium and a dense, lymphoplasmocytic infiltrate within the subepithelial connective tissue.
The lymphoid cells were a mix of CD20-positive B-cells and CD3- and CD4-positive T-cells, suggesting a benign, reactive tissue process.
Lymphoma was excluded following further investigation with flow cytometry.
A revised diagnosis of mucosal plasmacytosis was made based on the histopathological findings.
Independently, the patient had been referred to the oral and maxillofacial surgery unit by his dentist for evaluation of raised, erythematous lesions in the left maxillary buccal sulcus and alveolar mucosa (Figure 2). The lesions did not involve the attached gingiva. A biopsy was performed, which showed sheets of chronic inflammatory cells, predominately plasma cells, in the fibrous stroma of the specimen (Figure 3). The plasma cells were uniform and no significant mitotic activity was observed. The surface was partly covered by oedematous epithelium with focal areas of ulceration. Immunochemistry studies showed that the plasma cells were polyclonal for kappa and lambda light chains. A diagnosis of oropharyngeal mucous membrane plasmacytosis was made.
Fig. 2 Clinical photograph of intraoral involvement, showing swollen alveolar mucosa. The arrow indicates the alveolar gingival tissue biopsy site.
Fig. 3 Photomicrograph of biopsy, showing sheets of plasma cells throughout the submucosa (H&E; ×20).
A possible association with exposure to cinnamon or mint found in toothpaste was explored. The patient was advised to stop using toothpaste when brushing his teeth and to augment his oral hygiene with chlorhexidine mouthwash.
A subsequent review showed a dramatic improvement, with complete resolution of the oropharyngeal symptoms (Figure 4).
Fig. 4 Endoscopic view of supraglottic region, showing resolution of signs following withdrawal of suspected allergens.
Skin patch testing was requested in order to confirm and investigate other potential causative agents; this included exposure to antimicrobials, perfumes and flavourings, especially those commonly found in toothpaste. The results showed significant reactions to cinnamaldehyde, cinnamyl alcohol and a fragrance mix containing cinnamaldehyde.
Twelve months later, the patient had continued to avoid brushing with toothpaste and remained symptom-free.
Discussion
Twenty to 30 years ago, there were a number of reports of patients presenting with a sudden onset of painful, erythematous gingivae, which when biopsied were shown to have a dense, polyclonal, plasmacytic infiltrate in the connective tissue.Reference Owings1, Reference Perry, Deffner and Sheridan2 This condition was known by a variety of terms, particularly plasma cell gingivitis,Reference Lubow, Cooley, Hartman and McDaniel3, Reference MacLeod and Ellis4 and, at least in some instances, resolved after the withdrawal of allergens.Reference MacLeod and Ellis4, Reference Kerr, McClatchey and Regezi5 Hypersensitivity to components of chewing gum was implicated. Once the putative allergens were removed from this product, the number of cases of plasma cell gingivitis reduced, although sporadic cases were still reported.Reference Silverman and Lozada6, Reference Sollecito and Greenberg7
Plasma cell lesions involving other oral mucosal and upper aerodigestive tract sites have been less frequently reported. These more extensive lesions have been reported in the pharynx, palate, buccal mucosa, tongue, larynx and trachea, and may or may not be accompanied by gingival lesions.Reference White, Olsen and Banks8, 9 This condition has been termed plasma-cell orificial mucositis, plasma cell mucositis or mucous membrane plasmacytosis.Reference White, Olsen and Banks8, Reference Ferreiro, Egorshin, Olsen, Banks and Weiland10, Reference Kaur, Thami, Sarkar and Kanwar11 It affects middle-aged people, with a male predominance. The usual description is of a red, slightly elevated, ‘cobblestone’ lesion, without ulceration, which may be associated with discomfort in the region, dysphonia, dysphagia and difficulty breathing.9, Reference Ferreiro, Egorshin, Olsen, Banks and Weiland10
The presenting symptoms and the clinical appearance in the current case fit this description. The histology in the present case also fits the previous reports of oedematous epithelium overlying connective tissue with an intense infiltrate of mature plasma cells.
In such cases, a neoplastic plasmacytic proliferation should be ruled out by demonstrating the polyclonal nature of the infiltrate, or via gene rearrangement studies.
• Mucosal plasmacytosis is an uncommon, non-neoplastic condition characterised by an intense plasma cell proliferation in the affected tissue
• This paper describes the case of a 59-year-old male patient with an unusual presentation of mucosal plasmacytosis involving the oropharynx, related to the use of toothpaste
• The likelihood of an allergic aetiology in this case was strengthened by the strong reaction to skin testing of cinnamon products
Mucous membrane plasmacytosis is not reported to progress to malignancy.9 However, since the condition is rare, there are no long-term studies with large numbers, and regular clinical review is recommended.
Unlike plasma cell gingivitis, in which the link with allergic reactions is well established, the association between mucous membrane plasmacytosis and allergy is less well recognised. The present case is unusual in that resolution of the mucous membrane plasmacytosis followed withdrawal of the suspected allergens, without further medication. The likelihood of an allergic aetiology in this case was strengthened by the strong reaction to skin testing of cinnamon products. Previous reports have described the use of corticosteroids, antibiotics and surgical debulking procedures, with inconsistent results.9
Conclusion
This report adds to the literature another case of the rare plasma cell disorder mucous membrane plasmacytosis. It also demonstrates an association with cinnamon products, acting as putative allergens.
