Maria Silvia Cardia

Administration of a single dose of recombinant human thyrotrophin enhances the efficacy of radioiodine treatment of large compressive multinodular goitres

objective  Patients with very large multinodular goitres, frequently found among elderly people, often suffering from cardiovascular or other disabling disorders, may be considered as unsuitable for surgery. We have evaluated the feasibility of relatively high‐dose 131I therapy in such patients. As subclinical or clinical hyperthyroidism is commonly found in these patients, associated with a low radioiodine (RAI) uptake at 24 h, we pretreated a group of patients with a single intramuscular injection of recombinant human TSH (rhTSH 0·45 mg) in order to increase the uptake of the therapeutic dose of RAI.

Prevalence and characteristics of postpartum thyroid dysfunction in São Paulo, Brazil

Postpartum thyroid dysfunction (PPTD) is an autoimmune disorder characterized by the development of transient hyperthyroidism and, more frequently, hypothyroidism (or both) during the first six months of the puerperal period. A variable incidence has been reported in part because of differences in the number of women studied, the frequency of thyroid assessment postpartum, diagnostic criteria and methodology. The aim of this study was to evaluate thyroid function, ultrasound images and titre of autoantibodies against thyroid antigens in a cohort of pregnant women who met the criteria of ‘normal’ thyroid gland structure on clinical examination and imaging and normal thyroid function tests without a significantly positive anti‐thyroid peroxidase (TPO) antibody titre (i.e. < 100 U/ml) in the first trimester.

Prolonged follow‐up of multinodular goitre patients treated with radioiodine preceded or not by human recombinant TSH

We really enjoyed the comprehensive review on the effects of recombinant human thyrotropin (rhTSH) in normal subjects and patients with goitre, by Nielsen et al . 1 in the December issue of Clinical Endocrinology 2004. In that paper it was mentioned that changes in thyroid volume of multinodular goitre patients treated with radioiodine (RAI) preceded by rhTSH were significantly higher, compared with the group that only received RAI. 2 We would like to present our results in the prolonged follow-up of MNG patients subdivided in the same two groups, namely, with prestimulation with rhTSH prior to 131 I therapy (rhTSH + RAI group) or 131 I therapy alone (RAI group). In all patients we have obtained, on a yearly basis, a computerized tomography estimate of the thyroid volume. We were able to follow up for an additional 3 years, 17 patients of the rhTSH + RAI group and 13 patients of the RAI-only group. Three elderly patients in this latter group died from cardiac disease and one was lost to follow-up. Thyroid function tests, serum antithyroid antibodies and serum Tg were also assayed. As mentioned in the paper by Silva et al ., 2 about 65% of the hrTSH + RAI and 22% of the RAI-only developed hypothyroidism in the first 12 months of follow-up and were treated with  -thyroxine. During the next three years, two additional patients (one in each group) had clinical and laboratory data that confirmed hypothyroidism and were also started on  -thyroxine. A relatively small percentage of patients (< 3%) may develop elevated anti-TPO and TSH-receptor antibodies with clinical signs of Graves’ disease. 3–5 Nineteen patients from both groups had a transient positive serum TRAb test, but no signs or symptoms of Graves’ disease. We conclude that autoantibodies to thyroid antigens may appear transiently in the prolonged follow-up of MNG patients treated with RAI. As can be observed in Fig. 1, there was a further decrease of the thyroid volume in both groups at the end of the 4-year period, but it was significantly more pronounced in the rhTSH + RAI group as compared with the RAI-only group. The higher volume reduction in rhTSH + RAI group happened during the first year after RAI treatment. During the additional 3 years, the volume reduction continued, but there was no significant difference between the groups (thyroid volume reduction: RAI group 19·6 ± 18·9%; rhTSH + RAI group 17·3 ± 18·5%; P = 0·49;  with repeated measures). In 12/17 rhTSH + RAI patients and 8/13 in RAI patients the final thyroid volume at 4 years was reduced to about 20% of the 12 months MNG volume. In the RAI group, we also observed that in 2/13 patients, the 4-year volume actually increased as compared with the 1-year volume, respectively, from 123 and 129 ml in 1 year to 132 and 138 ml in 4 years. In conclusion, although no additional benefit of one treatment over another is observed in the following 3 years of follow-up, the initial difference in thyroid volume reduction is maintained.

Aspectos ultra-sonográficos e prevalência da tireoidite pós-parto em gestantes sem disfunção tireóidea atendidas em hospital público de São Paulo

We evaluated thyroid function, ultrasound images and presence of autoantibodies in a mixed racial group of 800 unselected primiparous or multiparous (1-7 previous pregnancies) pregnant women attended in a public hospital in the city of Sao Paulo. Forty-six patients were excluded from the study because of a confirmed diagnosis of a thyroid condition. Thus, a total of 754 women were available for further studies in the postpartum period. A relatively large number of those patients (n= 386) were lost or unavailable to follow-up either before or after delivery. A cohort of 386 puerperal healthy women was followed-up regularly at 3, 6, 12 and 24 months during the postpartum period, with regular thyroid function tests, random urine iodine measurements, assays for serum autoantibodies against thyroid antigens and imaging by ultrasound. Twenty-nine patients had a transient rise of anti-TPO-Ab characterizing an autoimmune reaction. These antibodies titres progressively declined or became negative. Moreover none of these patients have evidence for altered thyroid function during the 18-24 months of follow-up. Forty-nine patients (13.3%) changed their thyroid status, mainly to hypothyroidism, indicating the presence of a postpartum thyroid dysfunction (PPTD). Further follow-up studies have evidenced that at 18-24 months of examination 42/49 had serum levels of anti-TPO-Ab that were more elevated as compared with the first year values. Predictive factors found during pregnancy for developing PPTD, were: (1) relatively low levels of anti-TPO-Ab (between 60 and 100U/mL) [odds ratio 3:1] and (2) ultrasonographic thyroid structural changes in the first trimester [odds ratio 3.5:1]. In conclusion, the prevalence of PPTD was 13.3% considering only those postpartum women actually followed-up (n= 368). A transient form of thyroid autoimmune reaction, characterized by elevated serum titers of anti-TPO-Ab that further declined and reached the normal range, was observed in 29 puerperal women.

Bioequivalência de Preparações Comerciais de L-Tiroxina (100 e 200µg): Avaliação em Pacientes Hipotireóideos Previamente Tireoidectomizados

A bioequivalencia e biodisponibilidade das preparacoes comerciais de L-tiroxina podem apresentar diferencas significativas entre si. O objeto do presente trabalho foi comparar variaveis sericas tireoideas (T4 e T3 totais, T4 livre e TSH endogeno) em pacientes previamente tireoidectomizados (ha mais de 5 anos) e sem evidencia clinica ou ecografica de tecido glandular cervical remanescente. Os referidos parâmetros foram medidos, por 15 dias, a intervalos de tempo regulares, durante administracao de solucao oral de L-tiroxina (100µg), presumivelmente de absorcao e biodisponibilidade ideais. Comparou-se, em seguida, a oscilacao das mesmas variaveis com duas outras preparacoes comerciais, sob forma de comprimidos de L-tiroxina (LT4A e LT4B) nas doses de 100µg/dia e a seguir 200µg/dia. Nao se observou diferenca significativa entre a solucao oral e as duas preparacoes comerciais nos varios tempos de medida. Tampouco houve diferenca significativa entre os comprimidos de L-T4A e L-T4B em doses de 100µg ou de 200µg/dia. Concluimos que ambas as preparacoes apresentam biodisponibilidade e bioequivalencia adequadas nas condicoes utilizadas neste estudo.