Abstract

Objectives

Hashimoto’s thyroiditis is an autoimmune condition in which thyroid cells are damaged by immunological pathways that are both cellular and antibody-mediated.

Materials and Methods

The study analyzed data from 192 patients who tested positive for at least one of the anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-Tg) values and underwent thyroid ultrasonography during follow-up in an endocrinology outpatient clinic between June 2019 and 2023. The assessment included demographic information, levothyroxine (L-T4) doses, autoimmune diseases and markers, thyroid volume, and nodules.

Results

The study population was 87.5% female, mean age 48.98±13.45 years and mean follow-up 7.70±4.53 years. The dose of L-T4 administered median value was 50 mcg/day (minimum: 0, maximum: 225). Only 5.2% of patients achieved optimal vitamin D levels (>30 ng/mL), while 42.3% had severe vitamin D deficiency (<10 ng/mL). Additionally, 43.4% were found to have vitamin B12 deficiency. Thyroid ultrasonography revealed heterogeneous thyroid parenchyma in 93.2% of patients and at least one thyroid nodule in 34%. The rate of isolated anti-TPO positivity was 26.6%, while the rate of isolated anti-Tg positivity was 6.3%, and both autoantibodies were positive in 67.2% of patients. We observed a significant correlation between L-T4 doses and anti-TPO levels (r=0.294, p<0.001) as well as thyroid volumes (r=-0.239, p=0.001), but not with anti-Tg levels (r=-0.005, p<0.945). Type 1 diabetes mellitus, rheumatoid arthritis, and Addison’s disease were the most common comorbid autoimmune diseases. The most commonly co-occurring autoimmune markers were anti-nuclear antibodies (40.6%) and tissue transglutaminase IgA (27.3%).

Conclusion

Based on the data we obtained, we believe that increasing our awareness of other potential issues that may accompany this patient population in our clinical practice will help us understand how to manage these issues.