Thyroid Research Thyroid Research Archive Autoimmune Thyroid Disease

Serum antithyroid antibody concentrations decrease after treatment for Helicobacter pylori infection

(March 2005)

The background of the study. The cause of autoimmune thyroiditis is not known, but likely includes genetic and environmental factors. In this study the effect of treatment of infection with Helicobacter pylori (H. pylori), the bacteria that causes peptic ulcers, on serum antithyroid antibody concentrations was determined.

How the study was done. Five women with a high serum antithyroid peroxidase (anti-TPO) antibody concentration who tested positive for H. pylori infection were treated with a standard anti–H. pylori regimen of antibiotics and a drug to reduce acid secretion by the stomach. Serum anti-TPO antibodies and antithyroglobulin (anti-Tg) antibodies were measured at base line and periodically for up to two years in these women and also in women with similar findings who were not treated.

The results of the study. Serum anti-TPO antibody concentrations progressively decreased by 73 percent (range, 50 to 99) in the five women who received anti–H. pylori therapy, as compared with a decrease of 27 percent (range, 0 to 56) in the five untreated women. Serum anti-Tg antibody concentrations also decreased in the treated women, but not in the untreated women.

The conclusions of the study. Serum anti-TPO and anti-Tg antibody concentrations may decrease after treatment for H. pylori infection in patients with chronic autoimmune thyroiditis. These results suggest a possible role for H. pylori infection in the causation of autoimmune thyroiditis.

The original article. Bertalot G, Montresor G, Tampieri M, Spasiano A, Pedroni M, Milanesi B, Favret M, Manca N, Negrini R. Decrease in thyroid autoantibodies after eradication of Helicobacter pylori infection. Clin Endocrinol (Oxf) 2004;61:650-52.