Predictive effect of antithyroid antibody for relapse of Graves' disease

BackgroundThe remission rate in children with Graves' disease (GD) after 2-6years of antithyroid drug (ATD) treatment is 40-50%. It has been reported that it is difficult to predict the GD prognosis based on the thryroid stimulating hormone (TSH) receptor antibody (TRAb) level at the cessation of ATD treatment. We studied whether the persistence of negative TRAb at ATD treatment cessation increased the remission rate in pediatric patients with GD. MethodsWe included 22 patients diagnosed with GD who discontinued ATD treatment after confirmation of negative TRAb on two or more consecutive tests. Remission was defined as the maintenance of normal thyroid function, including serum TSH level, with negative TRAb more than 2years after ATD discontinuation. ResultsOf the 22 patients, 12 achieved remission (remission rate 54.5%), with no significant between-group difference in the median duration of ATD treatment in the remission and relapse groups (4.4 vs 3.9years). Of the 10 patients who relapsed, four (40.0%) relapsed within 2years after ATD discontinuation, and 4 (40.0%) relapsed more than 5years after ATD discontinuation. ConclusionsThe persistence of negative TRAb at ATD treatment cessation might indicate prolonged duration of remission but does not increase the final remission rate in patients with childhood-onset GD.