Introduction: Radioiodine treatment of hyperthyroidism of ophthalmopathy (GO) patients may cause or aggravate GO (in some 15%). We evaluated the activity and severity of ophthalmopathy in patients who acquired GO following radioiodine therapy.
Materials and methods: Over the years 20032005, 1500 hyperthyroid patients were treated with radioiodine at our Clinic. Of these, 50.9% suffered from Graves disease. Following their radioiodine treatment, in 30 females and 7 males (i.e. 5% of Gravespatients) of mean age 53.9±11.6 years, onset of GO was observed within 1-year post-treatment follow-up. I-131 treatment was only offered to patients with NOSPECS score <3 and CAS <3. Prior to their treatment, mean TSH concentration was 0.24±0.58 μU/m, mean 24-h I-131 uptake 54±14.6%, and mean I-131 activity 496±141 MBq.
Results: Six months post I-131 treatment, 68% of patients were cured while 32% required further methimazole medication. Over the 1-year follow-up all these patients were maintained euthyroid. In patients who developed GO after I-131 treatment, mean values of hTRAb and NOSPECS score were 24.3±18.8 U/l and 4.9±1.5 points, respectively, at the time of GO onset. Patients were qualified for SoluMedrol pulse therapy (8.0 g) and subsequent radiotherapy (20 Gy). Patients reported for control 1, 6 and 12 months post therapy. Mean concentration of hTRAb and NOSPECS score at 1, 6 and 12 months were: 11.8±10.1 U/l and 4.0±1.6; 14.5±15.6 U/l, 3.4±1.3; and 7.7±7.6 U/l and 2.5±1.2, respectively. Positive correlation between hTRAb and NOSPECS score was observed over the control period. IL-6 and IL-2 concentration prior to treatment and 1 month post treatment remained elevated and did not correlate with hTRAb nor with NOSPECS score.
Conclusions: Five percent of Graves disease patients developed severe GO following radioiodine treatment, thus association between radioiodine therapy and severe ophthalmopathy cannot be excluded. Preventive administration of glucocorticoids should be recommended in patients with Graves disease, even with mild ophthalmopathy.