Short-term results of treatment with 131I in patients with multinodular goiter: effect of the associated degree of hyperthyroidism and other variables

Thyroid Peroxidase Antibodies in Non-Autoimmune Hyperthyroidism Treated with Radioactive Iodine

“…Additionally, we found that the rate of hypothyroidism after RIT was not associated with the type of NIH (MNTG or TA), recurrences of hyperthyroidism and severity of nodular changes/focal lesions evaluated in ultrasonography. It has been reported that pre-existing thyroid autoimmunity may predict the development of hypothyroidism after RIT [13,15,16,22,23], although other reports including the present study did not support such association [24]. These discrepancies may be partially related to methodological differences between studies.…”

“…The concept of this study was based on practical observation that some patients with NIH have an elevated TPOAb level, which may be associated with a higher risk of developing hypothyroidism post RIT [15,16]. We found a 34 % prevalence of hypothyroidism at 12 months after RIT which overall is consistent with majority of studies evaluating this therapeutic outcome at a similar time point.…”

“…There is a limited number of studies which deal with the problem of elevated TPOAb levels in NIH treated with RIT, and they yielded inconsistent results. While Pisarek et al [14] found no association of post-RIT hypothyroidism in patients with baseline elevated TPOAb, Carceler et al [15] and Bolusani et al [16] found the increased risk of hypothyroidism in these cases. In this study, we evaluated the incidence of hypothyroidism in patients with nodular toxic goitre and toxic adenoma at 12 months after RIT in the relation to baseline TPOAb levels.…”

“…High rates of hypothyroidism in NIH treated with RIT were reported both in short-and long-term follow-up. Overall, the rate of hypothyroidism varies from 6 to 55 % within the first several years after RIT [15][16][17][18]. Predictably, it has been suggested that the rate of hypothyroidism may be influenced by a high initial size of the thyroid gland [9,19], prior antithyroid treatment [16], small goiter [9], and a high RAI dose [13].…”

“…These discrepancies may be partially related to methodological differences between studies. For example, in studies evaluating the outcomes of RIT in NIH, Carceller et al [15] included several subjects who were TRAb positive at the time of NIH diagnosis, while in the study of Bolusani et al [16] NIH was diagnosed solely by imaging techniques and baseline TRAb was not measured. This may suggest that in these reports a subset of subjects with coexisting Graves' disease were analysed, while the diagnosis of NIH based on scintigraphic appearance alone may be misleading because the scintigraphic 'hot' area may represent healthy background tissue but infiltrated by lymphocytes [25], as for example in Marine-Lenhard syndrome -a rare variant of Graves' disease with coexistent autonomous thyroid nodules [26,27].…”