BBackground. Helicobacter pylori (HP) is an infection related to metabolic and autoimmune disease Hashimoto thyroiditis (HT). HP-modified microRNA (miRNA) expression leads to various disorders. We aimed to evaluate circulatory miR-146a-5p and miR-155-5p expression in HT and to investigate their correlations with the clinical profile of HT and HP infection.

Methods: We enrolled 100 subjects; 50 participants as healthy control and 50 patients with HT. The diagnosis of HP- infection by HP antigen in stool and antibodies against cytotoxic-associated gene A (Cag-A). We tested serum antibodies against thyroid antigens. We used Quantitative real-time RT-PCR for the assessment of serum miR-146a-5p and miR-155-5p.

Results: Among 100 studied participants, patients inf*. Concerning had significantly higher values of miR-146a-5p (3.94±0.8), compared to HT patients without HP infection (1.84±0.3) and control group (0.98±0.1), p value˂0.001*. Concerning miR-155-5p, there were statistically significant higher values in HP infection (3.61±2.2) compared to HT patients without HP infection (1.91±1.1) and control group (0.90±0.35), p value˂0.001*. There were significantly positive correlations with nausea, vomiting, heartburn, anti-TPO, anti-TG, TSH, HP antigen, and Cag-A. On the opposing, they were negatively correlated with FT3 and FT4. linear regression analyses revealed that the only variables independently associated with miR-146a-5p were anti-TPO and FT4. Whereas the only variables independent associated with miR-155-5p were anti-TPO and FT3, p value˂0.001*.

Conclusion: miR-146a-5p and miR-155-5p overexpressed in patients with HT, more specifically in patients infected by HP and they were significantly correlated to gastrointestinal symptoms thyroid dysfunction, and autoimmunity.