Abstract: ［Abstract］〓Objective〖HTSS〗〓To compare the vitamin D status in children with Hashimoto thyroiditis(HT) and Graves disease(GD)，and to explore the role of vitamin D in the internal relationship between the two diseases.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓Forty cases with HT and 37 cases with GD were collected from Shijiazhuang Han nationality. Four milliliter fasting venous blood samples of all the patients were collected in the morning to determine 25 hydroxyvitamin D(25OHD), thyroid stimulating hormone(TSH), total thyroxine(TT4), total triiodothyronine(TT3), free thyroxine(FT4), free triiodothyronine(FT3), thyrotropin receptor antibody(TRAb), thyroid globulin antibody(TGAb) and thyroid peroxidase antibody(TPOAb). The lengths, widths and thicknesses of the left and right lobes of the thyroids were measured by ultrasound, and the thyroids volume were calculated. The iodine of the middle part urine in the morning was measured by electrochemical method.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The levels of FT3, FT4, TT3, TT4 and TRAb in HT group were significantly lower than that of GD group, TSH and TGAb were significantly higher than those in GD group(P＜005). There were no significant differences in 25OHD and TPOAb levels between the 2 groups(P＞005). TGAb in HT group with thyroid volume was significantly higher than that in GD group, and TRAb was significantly lower than GD group(P＜005). There was no significant difference in thyroid volume, 25OHD and TPOAb between the two groups(P＞005). TGAb in HT group with the results of urine iodine was significantly higher than that in GD group, and TRAb was significantly lower than that in GD group(P＜005). There was no significant difference in urinary iodine, 25OHD and TPOAb between the two groups(P＞005). There was no correlation between 25OHD level and TSH, TRAb, TGAb, and TPOAb in HT group(P＞005). There was a weak positive correlation between 25OHD level and TPOAb in GD group(P＜005), but no correlation with TSH, TRAb and TGAb(P＞005).
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓There is no significant difference in serum 25OHD levels between children with HT and GD. Serum 25OHD level may not play a role in the internal relationship between the twodiseases.

Key words: Hashimoto disease, Graves disease, vitamin D