Extremely high doses of radioiodine required for treatment of Graves' hyperthyroidism: a case report

Abstract

Introduction: Radioactive iodine ( 131 I) is widely prescribed for treatment of Graves' disease. A dose of 370 to 555 MBq (10 to 15 mCi) is usually enough, but reports of improved remission rates with single doses up to 20-30 mCi, and 38.5 mCi at most, exist.

Predictive factors for the outcomes of Graves’ disease patients with radioactive iodine (131I) treatment

“…We, here have shown that 24-h RAIU above 46.31% was a predictive factor for treatment success. In contrast with several other reports [6][7][8][9][10][11][12][13][14], we found that previous reported parameters, such as age, gender, pre-RIT serum levels of FT3, FT4 or TSH were not effective predictive factors for treatment outcome, suggesting that high dose RIT or fixed-dose RIT has no advantages over the calculated-dose method based on clinical and laboratorial parameters. The predictive role of 24 h-RAIU in RIT can be supported by some published works.…”

“…Previous works have shown multiple predictive factors associated with the therapeutic outcome of GD, such as age, gender, pre-RIT serum levels of TSH or serum-free thyroxine (FT4), treatment with ATDs, thyroid gland mass, withdrawal of ATDs prior to RIT, and thyroid mass etc. [6][7][8][9][10][11][12][13][14][15]. Some scholars claimed that lower treatment success rates occurred in patients with high free T3 concentration, ophthalmopathy at presentation [16], higher 2-h radioactive iodine uptake (RAIU) [17], lower RIT dose, 99m Tc sodium pertechnetate thyroid uptake > 20.9%, and marked goiter [6,18], young male patients, and more severe cases of hyperthyroidism [7].…”

Predictive Factors of Outcomes in Personalized Radioactive Iodine (131I) Treatment for Graves’ Disease

“…In our study and consistent with several other reports, 7,[9][10][11][12][13]24 we also found that other clinical parameters, such as age, sex and pre-RIT serum levels of TSH, FT4 or FT3 had no influence on outcomes. The main weakness of this study is the lack of data on thyroid autoantibodies titers, especially TRAb levels.…”

“…However, previous ATD treatment was correlated with treatment failure in univariate logistic regression analysis, suggesting that ATDs do indeed have some effect on RIT outcome. 10,11 However, in our study using calculated-dose regimens, RAI dosage is related to and is calculated based on thyroid gland mass, which may minimize the effects of thyroid gland mass on the treatment outcome. 23 Nevertheless, this factor was not entered in the multiple stepwise logistic regression model, which may be due to our small sample or a correlation between previous ATD treatment and other factors.…”

“…Previous studies have shown lower treatment success rates in young male patients and more severe cases with hyperthyroidism, 9,10 larger goiters 10,11 and higher serum thyroid-stimulating hormone (TSH) receptor antibody (TRAb) levels. 12 This is also found in cases with low or high pretreatment thyroid uptake.…”