The Causes of Thyrotoxicosis, Clinical Features, and Treatment Strategies in a Former Iodine Deficient Area
Abstract
Thyrotoxicosis is a hypermetabolic condition caused by excess thyroid hormones in the circulation with/without increased production from the thyroid gland. In this prospective study, we aimed to investigate the causes of thyrotoxicosis, clinical features, and treatment strategies in a former iodine-deficient area. Thyroid function tests, antithyroid and antithyroid receptor antibodies, and routine thyroid ultrasonography was obtained, and a thyroid scintigraphy/radioactive iodine uptake test was performed on need. A statistically significant difference was found between toxic multinodular goiter (TMNG) and Graves’ disease (GD) groups when mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) values were analyzed. TSH levels were significantly lower in GD patients compared to those in TMNG and TNG patients, but free triiodothyronine (FT3) and free thyroxine (FT4) values were higher. A high level of TSH receptor antibody (TRAb) was observed in patients with normal antithyroid peroxidase (Anti-TPO). TRAb levels were found to be high. Anti-TPO and anti-thyroglobulin (Anti-Tg) levels were observed to be positively correlated with sT3 and sT4 levels. TMNG is the leading cause of thyrotoxicosis; despite sufficient iodide intake in our former iodine-deficient region, TMNG is characteristically seen in older patients with much lower thyroid hormone levels than GD. According to the study results, the diagnosis of patients with thyrotoxicosis, their clinical presentation, the treatment they will receive, early detection of postoperative complications were predicted
Keywords
: Thyrotoxicosis, Toxic multinodular goiter, Graves’ disease, TSH
Ethical Statement
Ethical approval
The study was performed according to the principles of the declaration of Helsinki as revised in 1983 and approval was obtained by the Ethics Committee of Karadeniz University Medical Faculty. The permission has been granted by Karadeniz University Medical Faculty of Ethics Committee via the resolution dated 18.11.2014 and no. 2014/81. All participants in the study obtained informed consent before entering the study.
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