Abstract: Purpose Retrospective analysis the serum thyroid stimulating hormone receptor antibody (TRAb) dynamic changes and its relationship with prognosis in adolescent Graves disease(GD) before and after 131I therapy. Methods 140 adolescent GD were treated with 131I. The patients were divided into TRAb-positive group（n=115） and negative group（n=25）before treatment in accordance with levels of TRAb. TRAb levels were measured after treatment 3,6,12,24,36 months in each group. Result Positive group the incidence of hypothyroidism was 10.4% and negative group was 28.0% (P<0.05).The levels of TRAb increased in turn in positive group from hypothyroidism,recurrence,remission,cure before treatment(P<0.01). TRAb of patients with cure reached a peak in 6 months and returned to normal 36 months. Remission reached a peak in 12 months and increased mildly 36 months. Recurrence showed change of M-type characteristics. Hypothyroidism increased markedly after treatment 12 to 24 months and 36 months was still higher than before treatment. The levels of TRAb increased in turn after treatment 36 months from remission, recurrence, hypothyroidism.There were significant differences compared with cure respectively.(P<0.01) Conclusion Dynamic monitoring TRAb levels contribute to clinical outcome and prognosis after 131I therapy adolescent GD .We should be cautious that therapy adolescent GD of TRAb negative with131I.

Key words: adolescent Graves disease, TSH receptor antibody, 131I therapy