Burning mouth syndrome and burning mouth in hypothyroidism: proposal for a diagnostic and therapeutic protocol.

BACKGROUND: Burning mouth syndrome (BMS) is a common disorder frequently affecting women past the 5th decade of age. It is characterized by oral burning, mainly involving the tongue, lip, and anterior palate, but without oral lesions or alteration showing in blood tests and/or instrumental findings.

OBJECTIVE: We proposed to exclude alterations due to thyroid function and echographic abnormality in formulating BMS diagnosis. The aim of this study was to propose a blood and instrumental protocol including thyroid function and echography to obtain a correct BMS diagnosis. In the absence of such an assessment, a number of patients with oral burning and hypothyroidism may erroneously be considered BMS patients.

STUDY DESIGN: For this study, a group of 123 patients initially diagnosed with BMS was selected, following use of the current preliminary diagnostic protocol for BMS (study group). A further 123 patients with dental problems and without oral burning were selected as a control group. All patients were submitted to further protocol based on a study of their thyroid function and echography.

RESULTS: Thirteen control patients showed some thyroid alteration compared with 85 patients of the study group. In relation to these further examinations, a therapeutic protocol based on use of thyroxine, lipoic acid, or clonazepam was applied for patients belonging to the study group. Fifty-eight patients (47%) showed hypothyroidism and were treated with thyroxine, and 37 (64%) of these showed a positive response (VAS 1 and 0). Twenty-seven patients (22%) evinced euthyroidism with an inhomogeneous parenchyma thyroid echographic pattern. These were treated with lipoic acid, and 23 (85%) of them responded positively (VAS 1 and 0). Thirty-eight patients (31%) showed euthyroidism and no echographic alteration. Only these were considered to be true BMS patients and were treated with lipoic acid. Only 10 (26%) of these patients responded positively (VAS 1 and 0).

CONCLUSIONS: This study reveals that subjects with thyroid alterations are often considered to be BMS patients and that hypothyroidism could be responsible for oral burning and/or dysgeusia in some supertaster subjects. For these reasons, we propose that the study of thyroid function be inserted in the diagnostic process for BMS patients.