Conversion to Graves disease from Hashimoto thyroiditis: a study of 24 patients

ABSTRACT Objective: The conversion of Hashimoto's thyroiditis (HT) to hyperthyroidism due to thyrotropin receptor antibodies is intriguing and considered rare. The contribution of TSH receptor blocking antibodies (TRAb), which may be stimulators (TSAb) or blockers (TBAb), is suspected. We describe clinical and biological variables in a series of patients switching from Hashimoto's thyroiditis to Grave's disease. Subjects and methods: Retrospective case study of 24 patients with Hashimoto's thyroiditis followed during 48 ± 36 months that developed later Graves' disease (GD). These variables were analysed in the hypo and hyperthyroid phase: age, sex, initial TSH, free triiodothyronine (fT3), free thyroxine (fT4), anti-TPO, TBII antibodies, parietal cell autoantibodies, time between hypo and hyperthyroidism, thyroid volume and levothyroxine doses (LT). Results: In HT, mean TSH was 9.4 ± 26.1 UI/L and levothyroxine treatment was 66.2 ± 30.8 µg/day. The switch to GD was observed 38 ± 45 months after HT diagnosis. As expected, we found significant differences on TSH, FT3, FT4 and TBAb levels. Three out of 14 patients had parietal cell autoantibodies. In two of these three cases there was an Helicobacter pylori infection. There were no significant differences between HT and GD groups with respect to thyroid volume. Conclusions: To our knowledge, large series documenting the conversion of HT to GD are scarce. Although rare, this phenomenon should not be misdiagnosed. Suspicion should be raised whenever thyroxine posology must be tapered down during the follow-up of HT patients. Further immunological and genetic studies are needed to explain this unusual autoimmune change.

Association between antiretrovirals and thyroid diseases: a cross-sectional study

Objective This study aims to estimate the prevalence of thyroid diseases and anti-TPO status. We searched for an association among presence of immune reconstitution and use of stavudine, didanosine and protease inhibitors with thyroid diseases. Materials and methods A cross-sectional study was performed to analyze the records of 117 HIV-infected patients who had their CD4+ cell count, viral load, anti-TPO, TSH and free T4 levels collected on the same day. Immune reconstitution was considered in those whose T CD4+ count was below 200 cells/mm3, but these values increased above 200 cells/mm3 after the use of antiretrovirals. The odds ratio obtained by a 2x2 contingency table and a chi-square test were used to measure the association between categorical variables. Results The prevalence of thyroid disease was 34.18%; of these, 4.34% were positive for anti-TPO. There was an association of risk between stavudine use and subclinical hypothyroidism (OR = 4.19, 95% CI: 1.29 to 13.59, X2 = 6.37, p = 0.01). Immune reconstitution achieved protection associated with thyroid disease that was near statistical significance OR = 0.45, 95% CI: 0.19 to 1.04, X2 = 3.55, p = 0.059. Conclusion The prevalence of thyroid disease in the sample studied was higher than what had been found in the literature, with a low positive anti-TPO frequency. The historical use of stavudine has an association of risk for the presence of subclinical hypothyroidism, and immune reconstitution has trends towards protection for the presence of thyroid diseases. .

Alternative complement pathway and factor B activities in rats with altered blood levels of thyroid hormone

Evaluating the activity of the complement system under conditions of altered thyroid hormone levels might help elucidate the role of complement in triggering autoimmune processes. Here, we investigated alternative pathway (AP) activity in male Wistar rats (180 ± 10 g) after altering their thyroid hormone levels by treatment with triiodothyronine (T3), propylthiouracil (PTU) or thyroidectomy. T3 and thyroxine (T4) levels were determined by chemiluminescence assays. Hemolytic assays were performed to evaluate the lytic activity of the AP. Factor B activity was evaluated using factor B-deficient serum. An anti-human factor B antibody was used to measure factor B levels in serum by radial immunodiffusion. T3 measurements in thyroidectomized animals or animals treated with PTU demonstrated a significant reduction in hormone levels compared to control. The results showed a reduction in AP lytic activity in rats treated with increasing amounts of T3 (1, 10, or 50 µg). Factor B activity was also decreased in the sera of hyperthyroid rats treated with 1 to 50 µg T3. Additionally, treating rats with 25 µg T3 significantly increased factor B levels in their sera (P < 0.01). In contrast, increased factor B concentration and activity (32 percent) were observed in hypothyroid rats. We conclude that alterations in thyroid hormone levels affect the activity of the AP and factor B, which may in turn affect the roles of AP and factor B in antibody production.

Autoantibody frequency in celiac disease

AIM: In our study, we investigated the levels of glutamic acid decarboxylase antibody (anti-GAD), islet cell antibody (ICA), thyroperoxidase antibody (anti-TPO), thyroglobulin antibody (anti-TG), antinuclear antibodies (FANA), antibodies to double-stranded DNA (anti-ds DNA), antibody to Sjõgren syndrome A antigen (anti-SSA), antibody to Sjõgren syndrome B antigen (anti-SSB), Smith antibody (anti-Sm), smooth muscle antibodies (ASMA), and antimitochondrial antibody liver-kidney microsome (AMA-LKM) in patients with celiac disease as compared to healthy controls and autoimmune hypothyroid patients. MATERIALS AND METHODS: A total of 31 patients with celiac disease, 34 patients with autoimmune hypothyroidism and 29 healthy subjects were included in this study. Anti-SSA, anti-SSB, anti-Sm, anti-ds DNA, anti-GAD, anti-TPO and anti-TG were studied by Enzyme-Linked Immunosorbent Assay (ELISA), and AMA-LKM, ASMA, ANA and ICA were studied by immunofluorescence. Clinical data and the results of free thyroxine-thyroid stimulating hormone (FT4-TSH) were collected from the patients' files by retrospective analysis. SPSS ver 13.0 was used for data analysis, and the χ2 method was used for comparisons within groups. RESULTS: The frequency of anti-SSA, anti-SSB, anti-GAD, anti-Sm, anti-ds DNA, AMA-LKM, ASMA, ANA and ICA were not significantly different between the groups. Levels of anti-TPO and anti-TG antibodies were found to be significantly higher (<0.001) in autoimmune hypothyroid patients when compared with other groups. CONCLUSION: In previous studies, an increased frequency of autoimmune diseases of other systems has been reported in patients with celiac disease. We found that the frequency of autoimmune antibodies specific for other autoimmune diseases was not higher in celiac disease.

O selênio e a glândula tireóide: um estudo em pacientes portadores de disfunções tireoidianas nos estados de Ceará e São Paulo / The selenium and thyroid gland: a study in patients with thyroid dysfunction in the states of Ceara and Sao Paulo

Introdução: O Selênio é um mineral fundamental para o homem, participa dos mecanismos antioxidantes, influencia o sistema imune e participa ativamente da homeostase da glândula tireóide.Objetivo: Avaliar o estado nutricional relativo ao selênio de pacientes adultos portadores de hipotireoidismo e hipertireoidismo em atendimento ambulatorial no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo e no Hospital Universitário Walter Cantídio da Universidade Federal do Ceará. Metodologia: Foram avaliados quatro grupos de pacientes com doença de Graves (Graves), Bócio Multinodular Tóxico (BMNT), Hipotireoidismo pós-tireoidectomia (Hipotireoidismo) e tireoidite de Hashimoto (Hashimoto) em dois estados, São Paulo e Ceará e paralelamente dois grupos controle (São Paulo e Ceará). Foram realizadas caracterização antropométrica e clínica. O Se foi analisado no plasma e eritrócitos, foi medida a atividade da GSH-Px, iodúria, MDA plasmático e dosagens de hormônios tireoidianos e Anti-TPO. O consumo alimentar foi estimado utilizando-se a técnica de recordatório 24 horas...

Tireoideopatias e gravidez / Diseases of thyroids and pregnancy

As doenças da tireóide têm mais prevalência no sexo feminino e, possivelmente, são secundárias aos efeitos dos esteróides sexuais no sistema imunológico. Daí advém à importância do esclarecimento das tireoidopatias e das maneiras de diagnósticá-las precocemente, a tempo de interferir em seu ciclo patogênico e evitar a ocorrência de danos materno-fetais. É necessário discernir entre o patogênico e as adaptações fisiológicas da gestação, estando necessariamente entre as doenças de rastreamento obrigatório nesse período. Hipotireoidismo é doença bastante freqüente em nosso meio, sendo de origem imunológica ou pela deficiência de iodo. Na gestação, é freqüentemente causado por tireoidite auto-imune ou por destruição da glândula. A doença de Graves é a causa mais freqüente de hipertireoidismo durante e fora do período gestacional. Contudo, apesar de apresentar menos prevalência em gestantes, seus efeitos são graves caso não diagnosticado e tratado em tempo hábil. A tireoidite pós-parto é mais comum em mulheres que têm concentração elevada de anticorpo antiTPO e apresenta gênese auto-imune, sendo influenciada pelo ciclo gravídico-puerperal. A presença de nódulos benignos, malignos e o câncer de tireóide ainda apresentam relação a ser esclarecida com o período gravídico.

The thyroid's diseases have greater prevalence in the female sex and, possibly, they are secondary to the effects of the sexual steroids in the immunological system. From there comes the importance of the clarification of the thyroid's diseases and its precocious diagnosis, in time to intervene in its pathological cycle and prevent damages for the embryo or for the mother. It is necessary to discern between the gestation pathological and physiological adaptations, the thyroid diseases being necessarity among the illnesses of obligatory tracking in this period. Hypothyroidism is frequent enough, due to its immunological origins of iodine deficiency. During gestation it is frequently caused by autoimmunity thyroiditis or gland destruction. Graves' disease is the hyperthyroidism most frequent cause during pregnancy of not. However, although its minor prevalence in pregnancy, its effects might be serious if it is not diagnosed and treated in time. Thyroiditis after-childbirth is more common in women who have high TPO antibodies concentration and presente autoimmunity origin, being influenced by the pregnancy-puerperal cycle. The presence of any kind of nodules and thyroid cancer still present relation with the pregnancy period to be clarified.

Spastic paraparesis, abnormal muscle biopsy and positive antithyroid antibodies.

A 35 year old lady presented with progressive spastic paraparesis and hyperintense signals in the spinal cord and brain. She was noted to have high titres of antithyroid antibodies and primary hypothyroidism. Her muscle biopsy showed perivascular lymphocytes around endomysial vessels. We highlight the association of spinal cord involvement and abnormal muscle biopsy in a case of Hashimotos encephalopathy.

Avaliação clínica e de sintomas psiquiátricos no hipotireoidismo subclínico / Evaluation of clinical and psychiatric symptoms in sub clinical hypothyroidism

OBJETIVO: Analisar e correlacionar características clínicas, sintomas psiquiátricos e dados laboratoriais no hipotireoidismo subclínico (HS). MÉTODOS: Estudo transversal comparando achados de 103 pacientes com HS aos de 60 indivíduos eutireoidianos. A avaliação clínica e a psiquiátrica foram baseadas, respectivamente, na escala de Zulewski e nos questionários de Hamilton A, Hamilton D e Beck. Todos foram submetidos a dosagens de tireotropina (TSH), T4 livre e antitireoperoxidase (ATPO). Variáveis contínuas foram analisadas por meio do teste t de Student, quando de distribuição normal, e dos testes de Mann-Whitney e Kruskal Wallis, quando "não normais". Variáveis categóricas por meio dos testes Qui-quadrado, exato de Fisher e Kruskal Wallis. Análise multivariada foi utilizada para estudo de variáveis de confundimento. RESULTADOS: O nível médio de TSH, no HS, foi 7,76 ± 2,9 æUI/mL e 1,66 ± 0,6 æUI/mL nos eutireoideanos (p=0,001). O nível de T4L foi menor no HS, apresentando correlação linear negativa com TSH. Ocorreu maior freqüência de escore clínico anormal (48,3 vs 67 por cento; p=0,020), de sintomas de depressão, pela escala de Beck no HS (20,5 vs 44,2 por cento; p=0,011) e de sintomas de ansiedade (86 vs 63,4 por cento; p=0,004) no HS. A presença de sintomas de depressão e ansiedade associou-se de forma positiva com pontuação no escore clínico e níveis de TSH. Não houve associação entre achados clínicos ou psiquiátricos e etiologia do HS, presença de ATPO, idade ou menopausa. CONCLUSÃO: O estudo aponta para associação entre HS, achados clínicos e sintomas psiquiátricos. Ensaios clínicos são necessários para avaliar uma possível melhora com levotiroxina.

Prevalência de anticorpos antimicrossomais em pacientes com esclerose múltipla / Prevalence of antimicrosomal antibodies in patients with multiple sclerosis

O objetivo deste estudo consiste em avaliar a prevalência de anticorpos antimicrossomais (AAM), a função tireóidea e a ocorrência de sintomas relacionados ao hipotireoidismo em pacientes com esclerose multipla (EM). Em um grupo de 21 pacientes com EM, foi realizado exameclínico, foram dosados o TSH, T4 e T4 livre e pesquisados AAM. A média de idade foi 41,05 anos e a média de tempo de doença foi 85,9 meses. Os sintomas relacionados ao hipotireoidismo foram fadiga, fraqueza, letargia e parestesias. Os AAM foram encontrados em 4 pacientes (19 por cento). O tempo de doença foi dividido em três períodos: <60 meses (3 pacientes AAM+/7AAM-), 60-120 meses (8 pacientes AAM-) e >120 meses (1 paciente AAM+/2 AAM-). Dois pacientes apresentaram níveis de T4 livre diminuídos, porém com T4 e TSH normais. Em 1 paciente, constatou-se hipotireoidismo subclínico, e em outro, hipotireoidismo clássico. Conclui-se que na avaliação dos pacientes com EM, em vista da falta de precisão na avaliação clínica do hipotireoidismo ocasionada pela sobreposição de sintomas referentes à EM, devam ser incorporadas as dosagens das provas de função tireóidea (PFT) e dos AAM.

Anticuerpos antitiroideos en hipotiroidismo congénito / Antithyroid antibodies in congenital hypothyroidism

El papel que los anticuerpos antitiroideos maternos pueden desempeñar en la etiopatogenia del hipotiroidismo congénito por atireosis es discutible. En este estudio se midieron los niveles séricos de antivuerpos antitiroideos en 12 pacientes hipotiroideos y en sus madres, con la finalidad de detectar la posible asociación entre enfermedad tiroidea autoinmune materna y displasia tiroidea fetal. En dos pacientes hubo anticuerpos antitiroglobulina, lo que apoya la teoría de la existencia de un proceso inmunológico contra la tiroides fetal en las primeras ocho semanas de festación, pero no descarta la existencia y/o coexistencia de otros factores etiopatogénicos

Influencia del nivel de hormonas tiroideas en las subpoblaciones de linfocitos T / Influence of thyroid hormone levels on T lymphocyte subpopulations

Para precisar si la disfunción tiroidea influye en los trastornos de la inmunidad mediada por células presentes en la enfermedad autoinmune del tiroides, se determinaron los niveles de linfocitos T totales y subpoblaciones de linfocitos T en: grupo I: 15 pacientes hipertiroideos, (ocho antes de recibir tratamiento y después, con drogas antitiroideas durante seis meses); grupo II: ocho pacientes eutiroideas (bocio toxico difuso en remisión) y grupo III: tres pacientes con hipotiroidismo primario no iatrogénico sin tratamiento. Los niveles de linfocitos T totales fueron normales en todos los pacientes. Los linfocitos T formadores de roseta activa estuvieron disminuidos (X=19) en pacientes en fase hipertiroidea, y normales (X=25) cuando se logró el eutiroidismo. La relación T4/T8 estuvo disminuida en pacientes hipotiroideos y aumenta en 2/7 pacientes con bocio tóxico difuso (BTD) en fase tirotóxica. Estos resultados apoyan la hipótesis de que en los trastornos (al menos en el orden cuantitativo) de las subpoblaciones de linfocitos T influyen los niveles de hormonas tiroideas. En este trabajo, además, se informan los resultados iniciales con la aplicación de la técnica de anticuerpos monoclonales para el estudio de las células T