Abdolali Aghili - General Physician, Student Research Committee, Babol University of Medical Sciences, Babol, Iran.
Morteza Alijanpour Aghamaleki - Assistant Professor of Pediatric Endocrinology, Non-Communicable Pediatric Diseases Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, IR Iran.
Mohammad Pornasrollah - The Clinical Research Development Unit of Amirkola Children s Hospital, Babol University of Medical Sciences, Babol, IR Iran.
Haj Ghorban Nooreddini - The Clinical Research Development Unit of Amirkola Children s Hospital, Babol University of Medical Sciences, Babol, IR Iran.

Background Hashimoto s thyroiditis (HT) is a common cause of thyroid diseases in children and the role of vitamin D (VD) is controversial. Therefore, the aim of this study was to investigate the influence of VD therapy on HT in children with hypovitaminosis D. Materials and Methods This randomized clinical trial study was conducted on 30 patients referred to Endocrine Clinic of Amirkola Children s Hospital (ACH) of Babol in Iran. The serum levels of calcium, T4, TSH, Anti thyroid peroxidase antibody (TPOAb), and Anti thyroglobulin antibody (TgAb) were checked, and ultimately the HT was diagnosed based on thyroid sonography and these findings. According to normal range of calcium> 8.4 mg/dl and low level of VD, the patients were divided into deficient ( Results The mean of anti-Tg and anti-TPO statistically decreased was 801.63±1172.29 vs. 492.38±1021.48 (p=0.01), and 728.21±1004.28 vs. 441.57±603.26 (p=0.01) before and after intervention, respectively so that this reduction was higher in 2-12 year-old patients. Moreover, the mean of thyroid volume in both right and left lobes statistically reduced was 3.97±3.18 vs. 3.21±2.67 (p=0.002), and 3.32±2.94 vs. 3.21±3.96 (p=0.008) before and after intervention, respectively so this decrease was higher in≥13 year-old children (p<0.05). Conclusion This study showed that the level of autoantibodies and thyroid volume were decreased, after VD intervention. Thus, it is suggested that the serum VD level should be routinely checked in these patients and when observing hypovitaminosis, an appropriate treatment and prevention with VD should be carried out to avoid recurrent VD deficiency.

Autoimmune thyroid, Hashimoto s Thyroiditis, Thyroid Volume, Vitamin D