Background: Radioactive iodine therapy (RAI) is established as a safe and effective treatment for adults with Graves disease. As thyrotoxicosis in children is rare, it is difficult to obtain high quality evidence about the safety and efficacy of RAI. We present data from our centre between 2007 and 2017.
Methods: 20 paediatric patients with hyperthyroidism (16F), median age 15.7 years (range 10.819.3) had RAI in our centre either one or two doses. Median follow-up for all patients was 1.4 years (09 years).
Results: All patients received an initial median iodine-131 (I-131) dose of 607 MBq (419803 MBq). The primary indications were: definitive treatment following antithyroid drug treatment (ATD) (16/20; 80%), intolerance/sensitivity to ATD (2/20; 10%), poor compliance to ATD (1/20; 5%) and acute psychosis secondary to thyrotoxicosis (1/20; 5%). Following one dose of I-131, 15/20 (75%) patients became hypothyroid in median 3.5 months (120 months), 3/20 (15%) relapsed median 7 months (range 119 months) following RAI. Two (10%) were lost to follow up. The 3 relapsed patients had a second dose of RAI median 600 MBq (421618 MBq). One had allergic hypersensitivity to ATD and her presenting FT4 was >150 pmol/l. A second RAI dose was given 9 weeks after the first and the fT4 normalised. However, one year later she relapsed and required definitive treatment with surgical thyroidectomy. Another patient had a large goitre and went hypothyroid after 9 years. The final patient was rendered hypothyroid within one month following second RAI. Fifteen patients who were hypothyroid initially remain well on thyroxine replacement median 100 μm (50200 μm) following RAI.
Discussion: Whilst our cohort is small, our data suggest that RAI is a safe and effective definitive treatment for hyperthyroidism in children and adolescents. Long term follow up data is difficult to obtain due to the rarity of hyperthyroidism in paediatric patients but can be achieved by collaboration between centres.
22 - 24 Nov 2017
British Society for Paediatric Endocrinology and Diabetes