Of the 33 LT3S patients, 6 patients were with concomitant low TSH concentrations, thereby indicating changes in the hypothalamic-pituitary regulation; 1 patient was with concomitant low FT4 concentration, which may also be due to an impaired hypothalamic or pituitary regulation.22 Despite these changes, serum concentrations of anti-TG Ab, anti-TPO Ab, anti-TM Ab, and anti-TR Ab were normal in all patients enrolled in our study, which conformed there was no autoimmune thyroid disease in all the 39 individuals. Here, TG is linked to autoimmune thyroid disease.