Levels of salivary IgA in patients with minor recurrent aphthous stomatitis: a matched case-control study

Recurrent aphthous stomatitis (RAS) is the most common oral mucosal disease. Despite plenty of studies on aetiopathogenesis of RAS, a definite cause is not clear. The objective of this study was to determine the potential changes of salivary IgA and salivary flow rate in patients affected with minor form of RAS. Levels of salivary IgA in 33 patients with acute RAS (minor form) and 33 matched healthy controls were determined using enzyme-linked immunosorbent assay. Resting salivary flow rates were determined too. Both measurements, levels of salivary IgA and resting salivary flow rate, were performed again for each RAS patient in remission phase. Levels of salivary IgA were significantly increased in acute phase of RAS [median (interquartile range)-124.94 mu g/mL (106.22-136.31)] in comparison with the levels in healthy controls [88.92 mu g/mL (76.85-93.91; P < 0.001)] and with the levels in remission phase [102.4 mu g/mL (84.6-120.16; P = 0.01)]. Even in the disease-free period (remission phase), levels of salivary IgA remained significantly higher in comparison with the levels in healthy controls (P = 0.01). Salivary flow rates, on the other side, were not influenced by the disease state (RAS vs. healthy), phase (acute vs. remission) or even gender (males vs. females). Marked increase of salivary IgA in acute and remission phases of the minor RAS may suggest a potential role for this immunoglobulin in pathogenesis of the disease. Salivary IgA may be an important aetiological agent in the pathogenesis of RAS, and hence, its immunomodulation may help prevent the disease.