Serum cytokine and T regulatory cell levels in patients with burning mouth syndrome

BACKGROUND: Burning mouth syndrome is a disorder usually associated with an unexplained, prolonged sensation of burning inside the oral cavity. Although the etiology is unknown, neural and psychologic factors and cytokines may be implicated in the pathogenesis of burning mouth syndrome. The aim of this study was to investigate the relationship between serum cytokine and T regulatory cell levels in patients with burning mouth syndrome with regard to depression and anxiety. METHODS: Thirty patients with burning mouth syndrome and 30 matched controls participated in the study. Serum cytokine levels were measured with cytometric bead array and T regulatory cells were defined as CD4(+)CD25(+)Foxp-3(+) cells by flow cytometry. The level of anxiety and depression were analyzed by means of the Speilberger State-Trait Anxiety Inventory and Zung Self-Rating Depression Scale. Visual analogue scale was used in the quantification of burning levels of patients. RESULTS: Serum IL-2 and TNF-alpha levels were significantly decreased in patients with burning mouth syndrome compared with controls [mean 16.79 +/- 8.70 vs. 37.73 +/- 41.05 pg/ml (P < 0.05) and mean 39.09 +/- 29.40 vs. 70.83 +/- 42.44 pg/ml (P < 0.01) respectively]. CONCLUSIONS: IL-2 and TNF-alpha might play a role in burning mouth syndrome. Burning mouth syndrome may occur as a sign of predisposition to autoimmunity. Presence of low levels of CD28(+) supports the provision that BMS might be a pre-otoimmune disease.