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-autoimmune disease.