Treatment of thyrotoxicosis.
ABSTRACT In this review, the causes of thyrotoxicosis and the treatment of syndromes with increased trapping of iodine are discussed. The benefits and the potential side effects of 3 frequently used therapies--antithyroid medications, thyroidectomy, and (131)I treatment--are presented. The different approaches to application of (131)I treatment are described. Treatment with (131)I has been found to be cost-effective, safe, and reliable.
- SourceAvailable from: Javier Oswaldo Rodríguez Velásquez
- [Show abstract] [Hide abstract]
ABSTRACT: The aim of this study was to evaluate response and compare the success rate of two different doses of iodine-131 (I) therapy in the treatment of Graves' disease and investigate the factors that may affect outcome. A retrospective analysis was carried out on 321 patients treated with I for Graves' disease. Group 1 (155 patients) received 8 mCi and group 2 (166 patients) received 12 mCi. The therapy was considered successful if euthyroidism or hypothyroidism was achieved within 1 year of therapy. The outcome was compared with multiple parameters. A significant difference in the outcome between the two groups was found in favor of the second group (P<0.001). Logistic regression analysis showed that lower dose, technetium-99m pertechnetate thyroid uptake greater than 20.9%, and moderate and marked goiter were independent variables associated significantly with a lower response rate (odds ratio 2.601, 4.023, and 3.309, respectively), whereas previous surgical treatment was associated with a higher response rate (odds ratio 3.071). No correlation was found between outcome and age, presence of exophthalmos, previous treatment with methimazole, and its duration. The response rate to the second dose was significantly increased compared with the first one by 27.8%; there was no correlation among the above-mentioned factors and its outcome. The third dose controlled the disease in 81.3% of the remaining patients and control was achieved in the rest after the fourth dose. I is a very effective therapy for Graves' disease, with a cure rate of 100% after four doses. Higher first dose activity is recommended in the presence of poor prognostic factors. The second dose is not necessarily increased in the nonresponders.Nuclear Medicine Communications 06/2014; 35(9). DOI:10.1097/MNM.0000000000000152 · 1.37 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: RESUMO A amiodarona é um anti-arrítmico frequentemente usado para tratar taquidisritmias cardía-cas. No entanto, tem efeitos laterais em vários órgãos e em particular na tiróide. Os efeitos sobre a função tiroideia podem ser induzidos pelo seu conteúdo em iodo ou intrínsecos ao fármaco. A maioria dos doentes sob amiodarona permanecem eutiroideus, mas 14-18% podem desen-volver disfunção tiroideia. O hipotiroidismo é mais frequente em áreas onde o aporte iodado é suficiente, enquanto o hipertiroidismo é mais habitual em áreas com carência iodada. Outros factores como o sexo, idade e existência de doença tiroideia prévia podem influenciar as manifestações clínicas. A disfunção tiroideia da amiodarona é multifactorial. A falência do escape ao efeito Wolff-Chaikoff responde pelo quadro de hipotiroidismo; o quadro de tireo-toxicose ocorre por síntese aumentada das hormonas tiroideias (tipo 1) ou destruição tiroi-deia (tipo2). O diagnóstico, sugerido pela clínica, é estabelecido laboratorialmente. No contexto de hipoti-roidismo, o tratamento será de substituição com levotiroxina. Na situação de tireotoxicose, impõe-se o diagnóstico diferencial entre tipo 1 e 2. No tipo 1 a terapêutica envolve tionamidas, associando ou não perclorato de potássio e/ou carbonato de lítio; já no tipo 2 a terapêutica implica glicocorticóides. Nos tipos mistos, pode justificar-se a terapêutica combinada. Casos refractários ou urgentes podem implicar terapêuticas como plasmaferése ou tiroidectomia. A suspensão da amiodarona deve ser ponderada sempre que possível e baseada em critérios cardiológicos. A dronedarona, já aprovada pela FDA, poderá constituir uma promissora alter-nativa à amiodarona. ABSTRACT Amiodarone is an efficient anti-arrythimic frequently used to treat cardiac arrhythmias. However, it has adverse effects in many organs in particular in thyroid. The effects on thyroid function can be divided in: iodine-induced and drug-intrinsic. Most of the patients under amiodarone remain euthyroid, but 14-18% can develop thyroid dys-function. Hypothyroidism is more frequent in iodine-sufficient areas, while hyperthyroidism is more