Patients with chronic hepatitis type C and interferon-alpha-induced hyperthyroidism in two-years clinical follow-up.

OBJECTIVES: Interferon-α (IFN-α) is a gold standard in the therapy of viral chronic hepatitis type C (CHC). However, such treatment might lead to thyroid dysfunction. Patients usually present hypothyroidism, but rarely also hyperthyroidism may develop. The aim of the study is to present two-year clinical follow-up of patients with CHC and IFN-α-induced hyperthyroidism (IIH), with special regard to the methods and efficacy of the therapy. METHODS: A group of 106 patients with CHC and IIH were analyzed. Subjects were divided into two groups according to etiology: group 1, with Graves' disease (GD) and group 2, with Hashitoxicosis (HT). The diagnosis of GD and HT was based on: clinical signs of hyperthyroidism, hormonal profile (TSH, fT4, fT3), level of thyroid autoantibodies (Tg-Abs, TPO-Abs, TSHRAbs). Treatment of hyperthyroidism was monitored by repeated clinical assessment and laboratory tests. RESULST: 28 patients (26 with GD of which 5 exhibited mild orbitopathy and 2 with HT) were treated with radioiodine [the average dose of was 17 mCi [668 MBq]. In adition 78 out of 80 patients with HT mostly ß-blocker therapy was successful (transient hyperthyroidism). At the end of the observation period, in group 1 remission was achieved in 17 (65.4%) cases, 6 (23.1%) patients showed hypothyroidism and 3 (11.5%) presented recurrence of hyperthyroidism. CONCLUSIONS: Most patients with IIH present Hashitoxicosis, while a minority of them develop Graves' disease. In a majority of patients with HT spontaneous remission of disease occurs. In patients with long-term hyperthyroidism, radioiodine therapy is an effective and well-tolerated.

Radioiodine therapy in patients with amiodarone-induced thyrotoxicosis (AIT).

INTRODUCTION: Amiodarone (AM) is frequently used in the therapy of patients with cardiac disorders. However, due to high iodine content, it has side effects on thyroid function. The use of radioiodine therapy (RIT) in amiodarone-induced thyrotoxicosis (AIT) with low radioactive iodine uptake (RAIU) is still controversial. In these patients therapeutic choices for refractory disease include surgery, antithyroid drugs, or glu ocorticosteriods. AIM: The aim of the study was to evaluate the efficacy of RIT in patients presenting AIT and low RAIU in two-year follow-up. PATIENTS AND METHODS: 40 patients (25 men and 15 women) aged from 63 to 83 years (x +/- SD: 66.2 +/- 5.0 years; median: 65 years) treated with RIT were included into the study. In these patients AM therapy was essential for the underlying heart disorder, while surgery, antithyroid drugs or glucocorticosteroids, were contraindicated. Forty seven patients with toxic multinodular goiter (TMNG) (39 women and 8 men), matched for age (67 +/- 12 yr; range 54-89 yr), were enrolled into the study as a comparative group. The diagnostic procedures included baseline thyroid function tests (thyrothropin - TSH, free triiodothyronine - fT3 and free thyroxine - fT4 levels), thyroid autoantibodies measurement (antithyroglobulin autoantibodies - TgAb, antithyroid peroxidase autoantibodies - TPOAb, anti-TSH receptor autoantibodies - TRAb), thyroid ultrasonography, thyroid scintiscan and RAIU assessment. RESULTS: Serum values of TSH, TgAb, TPOAb and TRAb were undetectable in both groups. In patients with AIT fT4 level was 18.7 to 38.7 pmol/l (mean: 27.1 +/- 5.8) and fT3 concentration was 3.9 to 5.6 pmo/l (mean: 5.7 +/- 1.4), while in TMNG patients level of fT4 was 31.5 to 22.2 pmol/l (mean: 25,3 +/- 5,8) and fT3 concentration was 3.8 to 4,2 pmo/l (mean: 4,2 +/- 0,2). Mean RAIU values after 5h and 24h in AIT patients were 2.3 +/- 0.5 and 3.1 +/- 0.9%, while in TMNG patients were 18,0 +/- 3,8 and 35,7 +/- 9,1%, respectively. A significant difference (p<0.001) between 5h and 24h RAIU in AIT compared to TMNG was noted. In all patients with AIT, a dose of 800 MBq of 131I was administered. During two-year-observation recurrence of hyperthyroidism was observed in two patients (5%) with TMNG. These patients received a second radioiodine dose 16.2 +/- 15 months later (the mean re-treatment dose was 735.93 +/- 196.1 MBq). In comparison, none of the patients with AIT required a second 131I dose and only one patient (2.5%) 6 months after ablative 131I dose needed anti-thyroid medication. Transient hypothyroidism was observed in only two patients (5%) with AIH, though was not observed in TMNG. During follow-up time, no sudden deaths in AIT patients were observed; one patient was diagnosed with prostate cancer, and in one patient acute toxic hepatitis after AM occurred. CONCLUSION: RIT may be a safe and useful method of AIT therapy in patients with low RAIU, in whom other treatment methods are contraindicated.