Helicobacter pylori eradication effects on thyroid hormones and autoantibodies in levothyroxine-resistant hypothyroid women

Abstract Background Helicobacter pylori ( H. pylori ) infection has been implicated in a range of gastrointestinal and extra-gastrointestinal conditions, including autoimmune thyroid disease. Objectives To evaluate H. pylori IgG, anti-TPO, anti-Tg, TSH, fT4, and fT3 levels in hypothyroid women at baseline and at two and four months after H. pylori eradication therapy, compare findings with healthy females, and examine associations between thyroid function parameters and autoantibody titers over time. Materials and methods This case–control study enrolled 100 women aged 20–52 years, divided into two groups. The case group included 50 women with established hypothyroidism and confirmed H. pylori infection unresponsive to high-dose levothyroxine, while 50 age-matched healthy women served as controls. Baseline measurements were obtained, with follow-up assessments conducted at two and four months after completion of H. pylori eradication therapy. Results Patients exhibited significantly lower hemoglobin, hematocrit, RBC, and WBC counts compared with controls, while red cell indices and platelet counts were comparable. Baseline H. pylori IgG, anti-TPO, and anti-Tg titers were significantly higher in patients and declined markedly at 2- and 4-months following AOC therapy. Patients also had elevated baseline TSH and reduced fT4 and fT3 levels, which improved progressively after eradication. Significant positive correlations were observed between TSH, thyroid autoantibodies, and H. pylori IgG, while fT4 and fT3 showed inverse correlations with thyroid autoantibodies at baseline and 2 months, indicating dynamic immunoendocrine interactions. Conclusions H. pylori infection in hypothyroid patients is associated with mild anemia, increased thyroid autoimmunity, and lower circulating levels of FT4 and FT3. Eradication therapy improved thyroid function and reduced autoantibody levels, supporting H. pylori eradication as a useful adjunctive strategy for optimizing thyroid hormone control.