Gastric parietal cell and thyroid autoantibodies in recurrent aphthous stomatitis patients with concomitant oral lichen planus

Background/Purpose: Gastric parietal cell antibody (GPCA), thyroglobulin antibody (TGA), and thyroid microsomal antibody (TMA) have not yet been reported in recurrent aphthous stomatitis (RAS) patients with concomitant oral lichen planus (OLP/RAS patients). This study mainly assessed the frequencies of serum GPCA, TGA, and TMA (GPCA/TGA/TMA) positivities in 44 OLP/RAS patients. Methods: The frequencies of serum GPCA/TGA/TMA positivities in 44 OLP/RAS patients, OLP/RAS patients of four different subgroups, 520 RAS patients, and 352 healthy control subjects were calculated and compared. Results: We found that 20.5%, 27.3%, and 31.8% of 44 OLP/RAS patients, 75.0%, 100.0%, and 100.0% of 4 OLP/major-typed RAS (OLP/major RAS) patients, 15.0%, 20.0%, and 25.0% of 40 OLP/minor-typed RAS (OLP/minor RAS) patients, 45.5%, 72.7%, and 54.5% of 11 atrophic glossitis-positive OLP/RAS (AG ⁺ OLP/RAS) patients, and 12.1%, 12.1%, and 24.2% of 33 AG-negative OLP/RAS (AG־OLP/RAS) patients had the presence of GPCA, TGA, and TMA in their sera, respectively. OLP/RAS patients and OLP/RAS patients of four different subgroups all had significantly higher frequencies of GPCA/TGA/TMA positivities than healthy control subjects. Moreover, OLP/RAS patients had a significantly higher frequency of TMA positivity than RAS patients, and OLP/major RAS and AG ⁺ OLP/RAS patients had significantly higher frequencies of GPCA/TGA/TMA positivities than RAS patients. Furthermore, OLP/major RAS patients had significantly higher frequencies of GPCA/TGA/TMA positivities than OLP/minor RAS patients. Conclusion: For OLP/RAS patients, the concomitant OLP may play a role in causing an increased frequency of TMA positivity, and major RAS and the concomitant AG are contributory factors causing the elevated frequencies of GPCA/TGA/TMA positivities.