Dissertations / Theses on the topic 'Hashimoto thyroiditis'

Orientadores: Arlete Maria dos Santos Fernandes, Denise Engelbrecht Zantut Wittmann<br>Dissertação (Mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas<br>Made available in DSpace on 2019-01-09T11:51:06Z (GMT). No. of bitstreams: 1 Moro_AlessandraQuintino_M.pdf: 1160579 bytes, checksum: da4d51faeb6041f68c9c786482aef230 (MD5) Previous issue date: 2013<br>Resumo: A disfunção autoimune, representada pelo hipertireoidismo da Doença de Graves (DG) e pelo hipotireoidismo da Tireoidite de Hashimoto (TH), ocorre de forma mais frequente em mulheres e interfere no mecanismo da reprodução, em especial no processo ovulatório. Existe o senso comum de que as disfunções tireoideanas diminuem o potencial de fertilidade das mulheres; entretanto, não existem estudos sobre a prevalência da infertilidade nesses grupos. Objetivos: Determinar a prevalência de infertilidade em mulheres com TH e DG e as possíveis variáveis associadas. Sujeitos e métodos: Foi um estudo de corte transversal. Mulheres com TH (n=66) e idade entre 18 e 60 anos e DG (n=193) com idade entre 18 e 50 anos, em seguimento no Ambulatório de Tireoidopatias do HC/UNICAMP, no período de agosto de 2010 a dezembro de 2011, foram entrevistadas com respeito às variáveis ginecoobstétricas: história de períodos de infertilidade, alterações do ciclo menstrual, história obstétrica e antecedentes familiares. Infertilidade foi definida como ausência de gravidez após período de exposição ?12 meses. Após a entrevista, seus prontuários foram revisados para determinar as características da doença: idade ao diagnóstico, tempo do diagnóstico, antecedentes de outras doenças autoimunes associadas, exames laboratoriais e de imagem. O estudo obteve aprovação do Comitê de Ética em Pesquisa da FCM/UNICAMP. Os critérios de inclusão foram: ao menos um ano de convívio com parceiro masculino e concordância em participar da pesquisa. Os dados foram anotados em ficha de coleta e posteriormente digitados em banco de dados elaborado para o estudo. Após a consistência do banco, foi realizada análise descritiva das variáveis gineco-obstétricas e características da doença, e foram aplicados os testes quiquadrado ou exato de Fisher, teste de Mann-Whitney e teste de Wilcoxon. Posteriormente, foi realizada a análise univariada com o cálculo de Odds Ratio bruto e respectivo intervalo de confiança (IC) de 95%, seguida pela regressão logística múltipla incluindo todas as variáveis, buscando aquelas significativamente associadas à infertilidade. O grau de significância estatística foi de 5%. Resultados: A prevalência de infertilidade foi de 52,3% e 47,0% nas mulheres, respectivamente com DG e TH. Na DG, as perdas gestacionais tiveram prevalência de 18,8% e 21,7% em mulheres com e sem infertilidade, enquanto na TH as perdas gestacionais ocorreram em 22,6% e 20,6% nos mesmos grupos. A média do número de gestações foi menor após o diagnóstico de DG e TH nas mulheres com idade ?35 anos. No mesmo grupo de idade, a média do número de gestações antes do diagnóstico foi de 1,68 (DP ±1,41) para DG e 1,48 (DP ±1,31) para TH. As alterações de ciclo menstrual na DG ocorreram em 47,5% e 35,9% das mulheres, respectivamente com e sem infertilidade, e na TH as taxas foram de 64,5% e 34,3% nos mesmos grupos. A única variável associada à infertilidade na TH foi o tempo de doença menor que seis anos. Não houve variável associada nas mulheres com DG. Conclusões: a prevalência de infertilidade foi alta e, no grupo de mulheres com idade ?35 anos, houve diminuição na média de gestações, mostrando o comprometimento da fertilidade das mulheres com DG e TH. Mulheres com TH com menos tempo de doença foram as mais afetadas pela infertilidade<br>Abstract: The autoimmune dysfunction, hyperthyroidism represented by the Graves disease (GD) and by hypothyroidism of Hashimoto's thyroiditis (TH), occurs more often in women and interferes in the mechanism of reproduction, especially in the ovulatory process. There is common sense that thyroid dysfunction decreases the fertility potential of women, however, there are no studies on the prevalence of infertility in these groups. Objectives: To determine the prevalence of infertility in women with TH and DG and possible associated variables. Subjects and Methods: This was a cross-sectional study. Women with TH (n = 66) aged between 18 and 60 years and DG (n = 193) aged between 18 and 50 years was followed at the Endocrinology Division, Departament of Clinical Medicine, School of Medical Sciences, University of Campinas (UNICAMP), from August 2010 to December 2011 were interviewed with respect to gynecological and obstetric variables: history of periods of infertility, menstrual abnormalities, obstetric history and family history. Infertility was defined as 12 months of unprotected sexual intercourse without conception. After the interview, their medical records were reviewed to determine the characteristics of the disease: age at diagnosis, time since diagnosis, history of other autoimmune diseases associated, laboratory tests and imaging tests. The study was approved by the Research Ethics Committee of the FCM/UNICAMP. Inclusion criteria were: at least a year of living with a male partner, and agreed to participate. Data were recorded on collection and subsequently entered into a Summary - xvii database designed for the study. After the database consistency, descriptive analysis was performed gynecological and obstetric variables and disease characteristics, and applied the chi-square or Fisher's exact test, Mann-Whitney and Wilcoxon test. Subsequently, univariate analysis was performed to calculate crude odds ratios and confidence intervals (CI) of 95%, followed by multiple logistic regressions including all variables significantly associated with those seeking infertility. The level of statistical significance was 5%. Results: The prevalence of infertility was 52.3% and 47.0% in women, with DG and TH respectively. In DG, the miscarriages had a prevalence of 18.8% and 21.7% in women with and without infertility, while in the TH pregnancy loss occurred in 22.6% and 20.6% in the same groups. The mean number of pregnancies was lower after the diagnosis of GD and HT in women aged ? 35 years. In the same age group, the mean number of pregnancies before diagnosis was 1.68 (SD ± 1.41) for DG and 1.48 (SD ± 1.31) for TH. Changes in the menstrual cycle in DG occurred in 47.5% and 35.9% of women, respectively with and without infertility, and TH rates were 64.5% and 34.3% in the same groups. The only variable associated with infertility in TH disease duration was less than six years. There was no associated variable in women with GD. Conclusions: The prevalence of infertility was high and, in the group of women aged ? 35 years, there was a decrease in average pregnancies, showing impairment of fertility in women with GD and HT. Women with TH with shorter disease were most affected by infertility<br>Mestrado<br>Fisiopatologia Ginecológica<br>Mestra em Ciências da Saúde

Hashimoto Thyroiditis (HT) or chronic lymphocytic thyroiditis is an autoimmune disease that causes the destruction of the thyroid gland by inflammatory infiltrates and consequently loss of function. This disease is spread worldwide and predominantly affects females. The consequences of alterations in its activity range from cretinism to the vascular changes. It is known that the enzymes ectonucleoside diphosphohydrolase triphosphate (E-NTPDase, EC 3.6.1.5, CD39), ecto-5'nucleotidase (EC 3.1.3.5, CD73) and adenosine deaminase (ADA, EC 3.5.4.4) are involved in regulating the immune response and thrombotic events, since they regulate extracellular levels of adenine nucleotides and nucleoside. Since HT patients have an autoimmune response and present microvascular changes, the objective of this study was to evaluate the influence of purinergic signaling in the regulation of microvascular dysfunction triggered by the disease determining the activity of the ectoenzymes involved in the metabolism of ATP in platelets from patients with HT in treatment with levothyroxine. Samples were collected from patients with HT treated with levothyroxine and from a control group. In this study we determined the activity of the enzymes E-NTPDase, ecto-5'-nucleotidase and E-ADA; detected the expression of the enzyme in platelets and E-NTPDase; and measured hormone levels of TSH and fT4 in patients with HT treated with levothyroxine and control group. Results obtained in the enzyme activity showed that patients with HT in hormone replacement with levothyroxine presented no significant changes when compared with the control group. In conclusion, levothyroxine used in patients with HT may reverse the effects of hypothyroidism when used regularly in these patients, while maintaining the enzyme activity in basal levels.<br>A Tireoidite de Hashimoto (TH) ou tireoidite linfocítica crônica é uma doença autoimune que causa a destruição da glândula tireóide por meio de infiltrados inflamatórios e consequente perda da função. Esta patologia encontra-se difundida mundialmente e acomete prevalentemente o sexo feminino. As consequências das alterações de sua atividade vão desde cretinismo à alterações vasculares. Sabe-se que as enzimas ectonucleosídeo trifosfato difosfo-hidrolase (E-NTPDase; E.C. 3.6.1.5; CD39), ecto-5 nucleotidase (E.C.3.1.3.5; CD73) e adenosina desaminase (ADA; E.C.3.5.4.4) participam tanto da regulação da resposta imune quanto de eventos trombóticos, uma vez que regulam os níveis extracelulares dos nucleotídeos e nucleosídeo da adenina. Visto que, pacientes portadores da TH possuem uma resposta autoimune e também apresentam alterações microvasculares, o objetivo deste estudo foi avaliar a influência da sinalização purinérgica na regulação das disfunções microvasculares desencadeadas pela doença, através da determinação da atividade de ectoenzimas envolvidas no metabolismo do ATP em plaquetas de pacientes com TH em tratamento com levotiroxina. Foram coletadas amostras de pacientes com TH em tratamento com levotiroxina e um grupo controle. Neste estudo determinamos a atividade das enzimas E-NTPDase, ecto-5 -nucleotidase e E-ADA, verificamos a expressão da enzima E-NTPDase em plaquetas e dosamos os níveis hormonais de TSH e fT4 em pacientes com TH em tratamento com levotiroxina, bem como do grupo controle. Os resultados obtidos na atividade das enzimas e na concentração dos nucleotídeos e nucleosídeo da adenina, não demonstraram alterações significativas quando comparamos os pacientes com TH em reposição hormonal com levotiroxina, com o grupo controle. Em conclusão, sugere-se que a levotiroxina usada em pacientes com TH pode reverter os efeitos do hipotireoidismo quando usada regularmente por estes pacientes, mantendo as atividades das enzimas em níveis basais.

Orientadores: Denise Engelbrecht Zantut Wittmann, Sarah Monte Alegre<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas<br>Made available in DSpace on 2018-08-28T02:28:01Z (GMT). No. of bitstreams: 1 Botelho_IlkaMaraBorges_M.pdf: 1340793 bytes, checksum: 6ef5a41b67a7eddca52fc55dea2f96d4 (MD5) Previous issue date: 2014<br>Resumo: Introdução: Vitamina D tem sido apontada como importante regulador da resposta imune. Estudos tem demonstrado haver relação entre insuficiência de vitamina D e presença de doenças autoimunes como Tireoidite de Hashimoto (TH). É possível que o processo autoimune na TH seja inibido em diferentes estágios pela vitamina D em sua forma ativa. Nossos objetivos foram estudar a prevalência de insuficiência de vitamina D e a relação de suas concentrações séricas com marcadores de função e autoimunidade tireoideana. Material e Métodos: Amostras de sangue foram coletadas de 54 pacientes com TH e 54 indivíduos saudáveis sem diagnóstico de TH com idade entre 18 e 75 anos. Foram realizadas dosagens séricas de vitamina D (25OHD), TSH, T4 livre, cálcio, fósforo, paratormônio (PTH), anticorpos anti-tireoperoxidase (AcTPO), anti-tireoglobulina (AcTG) e anti-receptor de TSH (TRAb). Volume tireoideano foi estimado por ultrassonografia. Foram coletados dados demográficos, de peso, altura, índice de massa corporal (IMC) e tempo de diagnóstico. Pacientes e indivíduos do grupo de controle foram pareados por idade e sexo. O nível de significância estatística adotado foi 5%. Resultados: Prevalência de insuficiência de vitamina D foi encontrada em 68.5% dos pacientes e em 38.9% dos indivíduos do grupo de controle (p =0,002). Houve uma correlação positiva entre níveis de AcTPO e maior volumetireoideano nos pacientes (r = 0,319; p= 0.019). Não houve correlação entre concentração de vitamina D, TSH, T4livre,TRAb, AcTGe volume tireoideano. Conclusões: Demonstramosmaior prevalência deinsuficiência de vitamina Dem pacientescom tireoidite de Hashimotoem relaçãoa indivíduos de um grupo controlesaudável, não havendo correlaçãocom o estado hormnal tireoideanooumarcadores séricos deautoimunidadeda tireóide.Por sua vez, maior volume da tireóidese associou a maior grau de infiltração inflamatóriaautoimune,refletido pelacorrelaçãocom maiores concentrações AcTPO<br>Abstract: Introduction: Vitamin D has been pointed out as an important immune response regulator. Studies have shown a relationship between vitamin D insufficiency and the presence of autoimmune diseases such as Hashimoto's Thyroiditis (HT). It's possible that the autoimmune process in HT is inhibited in its different stages by vitamin D on its active form .Our aims were to study the prevalence of vitamin D insufficiency and relationship of the serum concentrations with thyroid function and autoimmunity markers. Material and Methods: Blood samples were collected from 54 patients with HT and 54 healthy individuals without a diagnosis of HT, aged 18 to 75 years. We conducted serum 25OH vitamin D, TSH, free T4, calcium, phosphorus, PTH, TPOAb, TgAb and TRAb. Thyroid volume was estimated by ultrasound. Data on demographic, weight, height, body mass index and time since diagnosis were collected. Patients and control subjects were matched by sexand age. The significance level for statistical analysis was 5%. Results: Prevalence of vitamin D insufficiency was found in 68.5% of patients and in 38.9% of subjects in the control group (p= 0.002). There was a positive correlation between TPOAb and volume in patients (p= 0.019). There was no correlation between vitamin D concentration and thyroid volume, TRAb, TgAb, TSH or free T4. Conclusions: We demonstrated a higher prevalence of vitamin D insufficiency in patients with Hashimoto's thyroiditis compared to individuals of a healthy control group, no correlation with thyroid state hormonal or serum markers of thyroid autoimmunity. In turn, greater thyroid volume was associated with a higher degree of autoimmune inflammatory infiltration, reflected by the correlation with higher concentrations AcTPO<br>Mestrado<br>Clinica Medica<br>Mestra em Ciências

Ce travail a pour objectif d'adapter à la détection et à la caractérisation d'autoanticorps, la technique d'immunonephelemetrie sur supports microparticulaires. Le but est d'affiner le pouvoir discriminant de cette technique jusqu'à l'identification de la spécificité épitopique des anticorps décelés. Un premier groupe d'applications porte sur la détection des autoanticorps anti-thyroglobuline humaine. Un test de détection de ces autoanticorps anti-domaine antigénique deux de la molécule de thyroglobuline, a été développé. Il est basé sur l'aptitude des autoanticorps à inhiber les systèmes agglutinants thyroglobuline-anticorps monoclonaux anti-thyroglobuline ont ainsi été détectés et quantifiés chez tous les patients atteints de thyroïdite d'Hashimoto et dans plus du trois-quarts des patients présentant une maladie de basedow non traitée. Les résultats obtenus se comparent favorablement à ceux de l'immunofluorescence indirecte et de l'hemagglutination passive. Le système mis au point peut aussi se prêter au dosage de la thyroglobuline sérique par inhibition. La détection des autoanticorps anti-thyroperoxydase humaine est calquée dans son principe sur le protocole mis au point pour les anticorps anti-thyroglobuline. Ce test confirme la polyclonalité des autoanticorps anti-thyroperoxydase et leur réactivité préférentielle envers les épitopes localisés sur les domaines antigéniques a et b de la molécule de thyroperoxydase, épitopes impliques dans les maladies thyroïdiennes auto-immunes. Ces mêmes spécificités sont observées chez les patients atteints de thyroïdite d'Hashimoto et de maladie de basedow. Les données immunonephelemetriques sont en accord avec les résultats des autres moyens d'investigation et avec les autres éléments des dossiers cliniques

Le malattie della tiroide sono, insieme al diabete mellito, le endocrinopatie più frequenti in gravidanza (0.2-0.5%) e nel puerperio (5-10%). L’incidenza delle disfunzioni tiroidee clinicamente evidenti nelle donne in gravidanza è del 1-2% ma le forme subcliniche sono probabilmente più comuni. La tiroidite di Hashimoto rappresenta, sicuramente, uno dei fattori eziopatogenetici più importanti di ipotiroidismo. Si parla di ipotiroidismo subclinico quando ad un TSH aumentato si associano valori normali di FT4. Nel primo studio,condotto tra il 2006 e i 2008, sono state esaminate 40 donne con storia di aborti ricorrenti. Tutte le pazienti sono state sottoposte a screening tiroideo. 12 pazienti con valori di TSH >2.5 mUI/ml sono state sottoposte a terapia con L- thyroxina. Nel gruppo che ha ricevuto il trattamento sostitutivo il 67% ha presentato una gravidanza a termine e l’8,3% gravidanza pre-termine (34 settimane). Nel secondo studio sono state sottoposte a screening per valutare la prevalenza di ipotiroidismo in una piccola popolazione 50 donne gravide, nate a Civita Castellana, vicino a Viterbo, zona con alta incidenza di tiroidine autoimmune (S. di Hashimoto). Di queste, soltanto 6 (12%) hanno mostrato livelli di TSH superiori a 2.5 mUI/ml. Tali gravidanze, in donne sottoposte a terapia, sono giunte a termine. Le disfunzioni tiroidee sono spesso associate a complicanze durante la gravidanza come ipertensione, parto prematuro, basso peso alla nascita, distacco di placenta e morte fetale. La relazione tra ipotiroidismo subclinico ed esito della gravidanza non sono stati bene studiati. I programmi di screening possono individuare i soggetti con ipotiroidismo subclinico o quali dei rischi che si sviluppino patologie tiroidee, ma i costi, i rischi e i benefici dello screening dei disordini tiroidei che compaiono prima o durante la gravidanza devono essere considerati. Lo screening delle patologie tiroidee in gravidanza è raccomandato soltanto nelle donne considerate ad alto rischio sulla base della storia personale o familiare di patologie tiroidee o storia di altre patologie autoimmunitarie L’american College of Obstetrician and Gynecologist (ACOG) ha espresso parere negativo nei confronti dello screening di routine per la malattia tiroidea subclinica, poiché non c’è nessuna evidenza che l’individuazione ed il trattamento delle donne in stato di gravidanza con ipotiroidismo subclinico, possa migliorare gli outcome materni e fetali. La prevalenza di tiroiditi autoimmuni non è abbastanza elevata da giustificare lo screening su tutta la popolazione. Al contrario, in piccole popolazioni in cui la prevalenza delle tiroiditi autoimmuni è alta, dobbiamo proporre lo screening. Rilevanti studi hanno mostrato una associazione tra autoimmunità tiroidea nella gravidanza precoce e successivo aborto. In queste pazienti, lo screening nella fase precoce della gravidanza è probabilmente ciò che di meglio possiamo offrire.<br>Thyroid diseases are, together with diabetes, the most frequent endocrinal diseases in pregnancy (0.2-0.5%) and postpartum (5-10%). The incidence of overt thyroid dysfunction in pregnant women is around 1-2% but unrecognized subclinical forms of hypothyroidism are probably even more prevalent. Hashimoto’s thyroiditis seems to be the most important cause of hypothyroidism. Mild or subclinical hypothyroidism is characterized by normal serum free thyroxine (FT4) concentrations with elevated serum thyroid-stimulating hormon (TSH) concentrations. In the first study a sample of 40 women, whit history of recurrent miscarriages occurred between 2006 and 2008, was recruited. All women experienced thyroid screening. Twelve patients with TSH values at or above 2.5 mUI/ml were treated with thyroid replacement therapy. In the thyroid supplementation group, 8 out of 12 pregnancies (67%) ended in live birth, 1 out of 12 (8,33%) ended in pre-term live birth (34 weeks). In the second observation we undertook a thyroid screening study to evaluate the prevalence of subclinical thyroid disease in a small population of 50 pregnant patients who were born in Civita Castellana, near Viterbo,. These patients exhibited high incidence of chronic autoimmune (Hashimoto’s) thyroiditis. Of these, 6 (12%) showed a serum TSH level higher than 2.5 mUI/ml. These pregnancies treated with L-thyroxina resulted in live births. Even though subjects with unsuspected hypothyroidism or those at risk of developing thyroid disease can be detected by means of screening programs, costs, risks and benefits associated to screening before and during pregnancy must be considered at all. Screening for thyroid disfunction in pregnancy is highly recommended just in case women are considered ‘high risk patients’ due to personal or family history of thyroid disease as well as due to other autoimmune responses. Routinary screening has not been recommended by the American College of Obstetrician and Gynecologist (ACOG) because a clear relationship between prefetal treatment and successful birth outcome was not supported by unambiguous observations Clinical thyroid dysfunction has been associated with pregnancy complications such as hypertension, preterm birth, low birth weight, placental abruption, and fetal death. The relationship between subclinical hypothyroidism and pregnancy outcomes has not been investigated in a great detail. For example, the prevalence of autoimmune thyroiditis is usually not high enough to justify a full screening of the entire population; on the contrary when small populations with high prevalence of autoimmune thyroiditis are considered, a screening operation is fully recommended. Relevant studies have shown a connection between of thyroid autoimmunity in early pregnancy and subsequent miscarriage. In these patients screening in early pregnancy is most likely to be the best strategy to be accomplished.

INTRODUÇÃO: Cerca de 80% dos nódulos de tireóide com citologia indeterminada são benignos. É possível que a tomografia por emissão de pósitrons (PET) com 2-[18F]- fluoro-2-desoxi-D-glicose (FDG) ajude a identificar quais dessas lesões são malignas. A captação de FDG depende da expressão de GLUTs (transportadores de glicose transmembrana) e hexoquinases. Captação difusa de FDG no leito tireoidiano tem ainda sido associada à tireoidite autoimune crônica (TAC), embora haja evidências de que pacientes com parênquima tireoidiano aparentemente sadio possam ter essa alteração. OBJETIVOS: (1) Determinar a sensibilidade e especificidade da PET-FDG no diagnóstico pré-operatório de malignidade dos nódulos tireoidianos, especialmente daqueles com resultados citológicos indeterminados, e avaliar esse desempenho no subgrupo de pacientes com TAC. (2) Determinar a correlação entre o achado de captação difusa tireoidiana da FDG à PET com o diagnóstico histopatológico de TAC e compará-la às concentrações plasmáticas dos anticorpos antitireoidianos. (3) Determinar a correlação entre a expressão dos marcadores imuno-histoquímicos GLUT 1, GLUT 3, GLUT 12, hexoquinase 2 e hexoquinase 3 com o diagnóstico histopatológico dos nódulos e com a captação de FDG apresentada pelos mesmos. MÉTODOS: 56 pacientes com nódulo de tireóide (42 com citologia indeterminada, 10 compatíveis com carcinoma papilífero e 4 com citologia benigna) realizaram PET-FDG e foram submetidos à tireoidectomia. Os resultados da PET-FDG foram comparados com o diagnóstico histopatológico do nódulo, com o infiltrado linfocitário no parênquima tireoidiano, com o diagnóstico de TAC e com os resultados do estudo imuno-histoquímico de micromatriz tecidual de tecido correspondente ao nódulo tireoidiano puncionado e ao tecido tireoidiano não nodular. RESULTADOS: 1) Todos os 21 pacientes com câncer de tireóide (11 com citologia indeterminada) apresentaram captação focal de FDG na tireóide. 2) Captação focal de FDG correlacionou-se com maior risco de malignidade (p<0,001). 3) Dos 31 pacientes com nódulos benignos com citologia indeterminada, 12 não tinham captação focal de FDG (especificidade de 39%). 4) Captação difusa no leito tireoidiano à PET-FDG foi associada à presença de TAC no exame histopatológico (p=0,019). Porém, 5 pacientes, sem sinais de infiltrado linfocitário, apresentaram captação difusa à PET-FDG. 5) Imunoexpressão dos anticorpos contra GLUTs 1, 3 e 12 e hexoquinases 2 e 3 nas células epiteliais dos nódulos não esteve positivamente associada com captação de FDG e com malignidade. 6) Não houve associação entre captação difusa de FDG no leito tireoidiano e imunoexpressão desses marcadores no parênquima tireoidiano não nodular. CONCLUSÕES: 1) A PET-FDG tem alta sensibilidade para diagnóstico de lesões malignas de tireóide, com especificidade de 39% para nódulos com citologia indeterminada. 2) Captação difusa de FDG no leito tireoidiano está associada à presença de TAC, mas pode ocorrer em pacientes sem infiltrado linfocitário. 3) A imuno-histoquímica para os anticorpos contra GLUTs 1, 3 e 12 e hexoquinases 2 e 3 não contribui para a diferenciação de nódulos malignos dos benignos e não se associa com a captação de FDG pelos nódulos<br>INTRODUCTION: Around 80% of thyroid nodules with indeterminate cytological result are benign. Positron emission tomography (PET) with 2-[18F]-fluoro-2-deoxy- D-glucose (FDG) might help to identify malignant thyroid lesions. FDG uptake depends on GLUTs expression (transmembranous glucose transporters) and on hexokinases. Although diffuse FDG thyroid uptake has been associated with chronic autoimmune thyroiditis (CAT), there is some evidence that patients with apparently normal thyroid parenchyma can display this pattern of FDG uptake. OBJECTIVES: (1) To assess the sensitivity and specificity of FDG PET in identifying thyroid malignancy in the preoperative evaluation of thyroid nodules and evaluate these results in the subgroup of patients with indeterminate cytological results and in the subgroup with CAT. (2) To compare the finding of diffuse FDG thyroid uptake with the histopathologic diagnosis of CAT and with the serum levels of antithyroid antibodies. (3) To evaluate the immunoexpression by thyroid nodules of GLUT 1, GLUT 3, GLUT 12, hexokinase 2 and hexokinase 3 and to compare it with the histopathologic diagnosis of these nodules and with FDG uptake. METHODS: 56 patients with thyroid nodules (42 with indeterminate cytological result, 10 with papillary carcinoma and 4 with benign cytological result) underwent FDG PET and, subsequently, thyroidectomy. FDG PET results were compared with the histopathologic diagnosis of the nodule, lymphocytic infiltrate of thyroid parenchyma, CAT diagnosis and immunohistochemical results of tissue microarray of the tissue from the thyroid nodule and the normal thyroid parenchyma. RESULTS: 1) All the 21 patients with thyroid cancer (11 with indeterminate cytological result) had focal thyroid FDG uptake. 2) Focal FDG uptake was associated with malignancy (p<0.001). 3) From 31 patients with benign nodules whose cytological result was indeterminate, 12 did not display focal FDG uptake (specificity of 39%). 4) Diffuse FDG uptake in thyroid bed was associated with CAT in the histopathologic exam (p=0.019). However, 5 patients without lymphocytic infiltrate had diffuse FDG uptake. 5) Immunoexpression of GLUTs 1, 3 and 12 and hexokinases 2 and 3 by epithelial cells of thyroid nodules was not positively associated with FDG uptake and malignancy. 6) There was no association between diffuse FDG uptake in thyroid bed and immunoexpression of these markers in the normal thyroid tissue. CONCLUSIONS: 1) FDG PET has high sensitivity to the diagnosis of malignancy in thyroid bed, with a specificity of 39% for thyroid nodules with indeterminate cytological result. 2) Diffuse FDG uptake in the thyroid bed is associated with CAT, but can be found in patients without lymphocytic infiltrate. 3) Immunohystochemistry against GLUTs 1, 3 and 12 and hexokinases 2 and 3 does not add in the differentiation of malignant and benign thyroid nodules and is not associated with FDG uptake by these nodules

Chronic lymphocytic thyroiditis, also known as Hashimoto's thyroiditis (HT) is the most common cause of hypothyroidism in the Western world. It is an autoimmune disease, where thyroid follicles are gradually destroyed by a variety of cell and antibody mediated immune processes. The involvement of viral infections has been frequently suggested as a major environmental factor, but no conclusive data are available. We analyzed fine needle biopsies from 34 HT patients for the presence and the transcriptional state of human herpesvirus 6 (HHV6). Controls, represented by 28 patients with benign follicular epithelial lesions, showed a low prevalence of HHV6 (10%, 3/28), with low viral load, and the transcriptional pattern showed a latent infection. Instead, samples from HT had a high prevalence of infection (82% vs 10%, p= 0.001), significantly higher viral load, and low-grade acute infection in 71% of HHV6 positive HT biopsies. HHV6 was latent in the blood of the same HT patients with acute thyroid infection. Purification of epithelial cells show that HHV6 is 100-fold more abundant in thyroid cells than in lymphocytes infiltrating the lesion. The tropism of HHV6 for thyroid cells was verified by infection of Nthy-ori3-l, a thyroid follicular epithelial cell line. The results showed that Nthy-ori3-l cells are permissive to HHV6 replication. Both HHV6 variants support productive infection for the first 7 days p.i., and subsequently persist establishing latency. HHV6 infection induce the expression of HLA class 11 antigens on thyroid infected cells, whereas HLA class 1 antigen expression is not affected. Furthermore, Nthy-ori3-l cells infected with HHV6 become target for innate NK cell killing and NK cells from HT patients show a significantly more efficient killing of HHV6 infected thyroid cells than healthy controls. These observations suggest a potential role for HHV6 in the development or triggering of HT.

Papillary thyroid cancer (PTC) represents 80%-85% of thyroid cancer and its prevalence has been rising in the last decades. Primary thyroid lymphoma (PTL) accounts for 3% of extranodal lymphomas and about 5% of thyroid malignancies, having a prevalence of one or two cases per million people. Mucosa-Associated Lymphoid Tissue lymphoma represents approximately 30% of PTL. Both entities have an indolent course and a very good prognosis. Diagnosis is made by ultrasound and fine needle aspiration (FNA) or surgery specimen pathology. They have also been associated with HT, but pathogenesis and its links remains to be known. Treatment remains controversial and surgery is generally accepted in cases of disease limited to thyroid, as the present. Patients with thyroid nodules should be observed and followed. If there is an enlargement by ultrasound or clinical symptoms, FNA should be performed promptly. Patients with Hashimoto’s thyroiditis (HT) deserve additional surveillance, since this condition is associated with both PTC and PTL. In this case, the management with surgery and radioactive iodine ablation therapy was effective for both entities. Patients with thyroid nodules should be properly evaluated with ultrasound and thyroid function tests. If there is an enlargement of the neck, reported by symptoms or ultrasound, it requires further investigation. HT is associated to both PTC and PTL so if the enlargement of the nodules is on this context additional tests such as FNA should be performed. In this case, the patient was managed with surgery and radioactive iodine ablation therapy and it was effective for both entities.<br>Revisión por pares

Autoimmune diseases are endemic, but the disease mechanisms are poorly understood. A way to better understand these are to find disease-regulating genes. However, this is difficult as the diseases are complex, with several genes as well as environmental factors influencing the development of disease. A way to facilitate the search for genes responsible for the diseases is to use comparative genomic studies. Animal models are relatively easy to analyze since control of environment and breeding are obtained. The University of California at Davies – line 200 (UCD-200) chickens have a hereditary disease that is similar to systemic sclerosis. Using a backcross between UCD-200 chickens and red junglefowl (RJF) chickens we identified three loci linked to the disease. The loci contained immune-regulatory genes suggested to be involved in systemic sclerosis in humans, as well as a previously unidentified linkage between systemic sclerosis in UCD-200 chickens and IGFBP3. The Dark brown (Db) gene enhances red pheomelanin and restricts expression of eumelanin in chickens. The Db phenotype is regulated by an 8 kb deletion upstream of SOX10. Pigmentation studies are potentially useful when trying to identify pathogenic mechanisms and candidate genes in vitiligo The Obese strain (OS) of chickens spontaneously develops an autoimmune thyroiditis which closely resembles human Hashimoto’s thyroiditis. By using an intercross between OS chickens and RJF chickens, we found several disease phenotypes that can be used in an ongoing linkage analysis with the goal to find candidate genes for autoimmune disease. An important phenotype to record and add to the linkage analysis is autoantibodies against thyroid peroxidase, since this phenotype is a key feature in Hashimoto’s thyroiditis. Previous attempts to measure these titres in OS chickens have failed, hence an assay was developed for this purpose.

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014<br>Introduction: Hypothyroidism occurs in the adult population in 4 to 5 %. Hashimoto’s thyroiditis, an autoimmune disease, is the most common cause of hypothyroidism in areas of iodine sufficiency. Clinically is characterized by variable sized goiter, positive thyroid antibodies and euthyroidism or subclinical hypothyroidism. Patients and methods: The study considered all patients, followed by a single doctor at the outpatient clinic of a tertiary hospital. A specific database was defined with the Statistical Package for the Social Sciences Program (SPSS/IBM 19th version), the database included the gender and age at the first appointment; the results of each analytical evaluation and Levothyroxine prescription. Results: Were evaluated 164 patients; the majority were female 147 (90%), the meanage 48±16 years [12-80 years] and were followed since 2000 with a mean follow-up of 4±3 years [1-10 years]. All analytical parameters considered at each time – T3, T4, TSH, fT4 – presented a normal distribution, except for TPOAb and TgAb, that presented a distribution significantly different from the normal one. More than half of the patients (61%) presented at the first appointment with hypothyroidism, most were already under substitutive therapy, and the remaining presented naïve to therapy beginning therapy immediately at the first appointment. From the remaining naïve patients, 28% presented later with hypothyroidism, at an average rate of 9% per year. The thyroid antibodies variability was demonstrated to be rather elevated, regarding TPOAb values these can increase four times within the range, and at some time both anti-thyroid antibodies are negative while later either one, or both became positive. Levels of TPOAb seem to increase over time, and was demonstrated a direct and significant relation between TPOAb and TSH, showing a functional relevance of the antibody. Discussion and Conclusion: Thyroid antibodies presented a fluctuate evolution over time, and therefore a defective marker of HT, since it can exclude incorrectly the diagnosis; the most common thyroid auto-antibodies are not related between them; more than half of HT patients probably develop hypothyroidism in the early years after the diagnosis; the progressive nature of HT can be followed by TPOAb and T3; in the short term period, thyroid antibodies evolution wasn’t modified by substitutive therapy.<br>Introdução: O Hipotiroidismo tem uma incidência de 4 a 5% na população adulta. A Tiroidite de Hashimoto (TH), uma doença auto-imune, é a causa mais comum de hipotiroidismo em áreas iodo-suficientes. Clinicamente caracteriza-se por bócio de tamanho variável, anticorpos anti-tiroideus e eutiroidismo ou hipotiroidismo subclínico. Doentes e métodos: O estudo considerou todos os doentes, seguidos por um único médico em consulta externa num hospital terciário. Foi definida uma base de dados específica com o Statistical Package for the Social Sciences Program (SPSS/IBM 19ª edição), a base de dados inclui o sexo e a idade na primeira consulta, os resultados de cada avaliação analítica e a prescrição de Levotiroxina. Resultados: No estudo foram avaliados 164 doentes; a maioria era do sexo feminino (90%), com idade-média 48±16 anos [12-80 anos] e foram seguidos desde 2000 com um tempo médio de seguimento em consulta 4±3 anos [1-10 anos]. Todos os parâmetros analíticos considerados em cada momento – T3, T4, TSH, fT4 – apresentam uma distribuição normal, com excepção de TPOAb e TgAb, que apresentam uma distribuição significativamente diferente de uma distribuição normal. Mais de metade dos doentes (61%) apresentaram-se na primeira consulta com hipotiroidismo, destes maior parte sob terapêutica substitutiva e os restantes era naïve à terapêutica, iniciando terapêutica na primeira consulta. Dos restantes doentes naïve à terapêutica, 28% evoluíram mais tarde para hipotiroidismo, a uma taxa média de 9% por ano. Foi demonstrado que a variabilidade dos anticorpos antitiroideus é consideravelmente elevada; os valores de TPOAb estes podem variar quatro vezes dentro do intervalo; e ambos anticorpos em algum momento podem tornar-se negativos, ficando mais tarde um ou ambos anticorpos positivos. Os níveis TPOAb aumentaram ao longo do tempo e foi demonstrada uma relação directa e significativa entre o TPOAb e o TSH, evidencia do uma relevância funcional dos anticorpos. Discussão e Conclusão: Os anticorpos antitiroideus apresentam uma evolução oscilante com o tempo, e por esse motivo são um marcador imperfeito de TH, uma vez que pode excluir incorrectamente o diagnóstico; os anticorpos antitiroideus não estão relacionados entre si; mais de metade dos doentes com TH provavelmente desenvolve hipotiroidismo nos primeiros anos após o diagnóstico. A natureza progressiva da TH pode ser avaliada pelo TPOAb e T3; a curto-prazo, a evolução dos anticorpos anti-tiroideus não foi modificada pela terapêutica substitutiva.

RESUMO CONTEXTUALIZAÇÃO: A tiroidite de Hashimoto (TH) pode associar-se a diferentes níveis de disfunção tiroideia. Ainda não está esclarecido de que forma a disfunção tiroideia ligeira, a autoimunidade e a inflamação crónica contribuem para um risco cardiovascular aumentado nos doentes com TH. Desta forma, este estudo pretende avaliar o grau de insulinorresistência, o perfil lipídico e a inflamação de baixo grau nos doentes com TH. MÉTODOS: Este estudo inclui um total de 228 indivíduos com tiroidite de Hashimoto, que foram divididos em três grupos de acordo com os níveis de TSH - TSH 0.35-2.49 μUI/ml, TSH 2.50-4.94 μUI/ml e TSH>4.94 μUI/ml. Foram determinados os testes de função tiroideia, anticorpos anti-tiroideus, perfil lipídico, índices de insulinorresistência, proteína C reativa de alta sensibilidade, vitamina B12, ácido fólico e homocisteína. A análise estatística foi realizada com ANOVA, t-test de Student, correlações de Pearson e regressão linear múltipla. RESULTADOS: 93.9% da nossa população é do sexo feminino e a média das idades é 47.1±15.4 anos. Não foram encontradas diferenças estatisticamente significativas entre os grupos, relativamente à idade, sexo e índice de massa corporal (IMC). Os valores de Modelo de Avaliação da Homeostasia da Insulinorresistência (HOMA-IR) foram estatisticamente diferentes entre os três grupos (p<0.001). No grupo total, níveis aumentados de TSH foram associados a valores superiores de triglicerídeos (r=0.206, p=0.002) e de HOMA-IR (r=0.209, p=0.002). Ambas as correlações se mantiveram significativas após ajustamento da idade, sexo e IMC. Foram encontradas correlações positivas entre os títulos de anticorpos anti-peroxidase tiroideia e colesterol total (r=0.166, p=0.013), colesterol LDL (r=0.173, p=0.01), Apolipoproteína B (r=0.190, p=0.006) e HOMA-IR (r=0.141, p=0.033). Os títulos de anticorpos anti-tiroglobulina correlacionaram-se positivamente com triglicerídeos (r=0.140, p=0.036). CONCLUSÕES: Os pacientes com TH e disfunção tiroideia ligeira apresentam um perfil lipídico mais aterogénico, bem como maior resistência à ação da insulina. Desta forma, o rastreio de comorbilidades cardiovasculares nestes doentes é essencial, de forma a fornecer um diagnóstico precoce e melhores decisões terapêuticas.<br>BACKGROUNDː Hashimoto thyroiditis (HT) may present different levels of thyroid function impairment. It remains unclear how mild thyroid dysfunction, autoimmunity and chronic inflammation contribute to an increased cardiovascular risk in HT. Therefore, this study aims to assess insulin resistance, lipid panel and low-grade inflammation in HT patients. METHODSː A total of 228 patients with HT were enrolled and divided into 3 groups, accordingly to TSH levels - TSH 0.35-2.49 μUI/ml, TSH 2.50-4.94 μUI/ml and TSH>4.94 μUI/ml. We assessed thyroid function tests and antibodies, lipid profile, insulin resistance indexes, high-sensitivity C-reactive protein, vitamin B12, folic acid and homocysteine. Statistical analysis was made using ANOVA, Student's t-test, Pearson's correlations and multiple linear regression. RESULTSː 93.9% of our population were women and mean age was 47.1±15.4 years. No significant differences were found between groups, regarding age, sex and body mass index (BMI). Homeostasis model assessment-insulin resistance (HOMA-IR) levels were significantly different in the three groups (p<0.001). In the total group, higher TSH values were associated to higher levels of triglycerides (r=0.206, p=0.002) and HOMA-IR (r=0.209, p=0.002), even after adjustment for age, sex and BMI. Thyroid peroxidase antibodies titers correlated positively with total cholesterol (r=0.166, p=0.013), LDL-cholesterol (r=0.173, p=0.010), ApoB (r=0.190, p=0.006) and HOMA-IR (r=0.141, p=0.033). Thyroglobulin antibodies correlated positively with triglycerides (r=0.140, p=0.036). CONCLUSIONSː HT patients with mild thyroid dysfunction present a more atherogenic lipid profile and higher resistance to insulin action. Therefore, screening for cardiovascular comorbidities in these patients is essential to provide an early diagnosis and better treatment decisions.

RESUMO CONTEXTUALIZAÇÃO: A tiroidite de Hashimoto (TH) pode associar-se a diferentes níveis de disfunção tiroideia. Ainda não está esclarecido de que forma a disfunção tiroideia ligeira, a autoimunidade e a inflamação crónica contribuem para um risco cardiovascular aumentado nos doentes com TH. Desta forma, este estudo pretende avaliar o grau de insulinorresistência, o perfil lipídico e a inflamação de baixo grau nos doentes com TH. MÉTODOS: Este estudo inclui um total de 228 indivíduos com tiroidite de Hashimoto, que foram divididos em três grupos de acordo com os níveis de TSH - TSH 0.35-2.49 μUI/ml, TSH 2.50-4.94 μUI/ml e TSH>4.94 μUI/ml. Foram determinados os testes de função tiroideia, anticorpos anti-tiroideus, perfil lipídico, índices de insulinorresistência, proteína C reativa de alta sensibilidade, vitamina B12, ácido fólico e homocisteína. A análise estatística foi realizada com ANOVA, t-test de Student, correlações de Pearson e regressão linear múltipla. RESULTADOS: 93.9% da nossa população é do sexo feminino e a média das idades é 47.1±15.4 anos. Não foram encontradas diferenças estatisticamente significativas entre os grupos, relativamente à idade, sexo e índice de massa corporal (IMC). Os valores de Modelo de Avaliação da Homeostasia da Insulinorresistência (HOMA-IR) foram estatisticamente diferentes entre os três grupos (p<0.001). No grupo total, níveis aumentados de TSH foram associados a valores superiores de triglicerídeos (r=0.206, p=0.002) e de HOMA-IR (r=0.209, p=0.002). Ambas as correlações se mantiveram significativas após ajustamento da idade, sexo e IMC. Foram encontradas correlações positivas entre os títulos de anticorpos anti-peroxidase tiroideia e colesterol total (r=0.166, p=0.013), colesterol LDL (r=0.173, p=0.01), Apolipoproteína B (r=0.190, p=0.006) e HOMA-IR (r=0.141, p=0.033). Os títulos de anticorpos anti-tiroglobulina correlacionaram-se positivamente com triglicerídeos (r=0.140, p=0.036). CONCLUSÕES: Os pacientes com TH e disfunção tiroideia ligeira apresentam um perfil lipídico mais aterogénico, bem como maior resistência à ação da insulina. Desta forma, o rastreio de comorbilidades cardiovasculares nestes doentes é essencial, de forma a fornecer um diagnóstico precoce e melhores decisões terapêuticas.<br>BACKGROUNDː Hashimoto thyroiditis (HT) may present different levels of thyroid function impairment. It remains unclear how mild thyroid dysfunction, autoimmunity and chronic inflammation contribute to an increased cardiovascular risk in HT. Therefore, this study aims to assess insulin resistance, lipid panel and low-grade inflammation in HT patients. METHODSː A total of 228 patients with HT were enrolled and divided into 3 groups, accordingly to TSH levels - TSH 0.35-2.49 μUI/ml, TSH 2.50-4.94 μUI/ml and TSH>4.94 μUI/ml. We assessed thyroid function tests and antibodies, lipid profile, insulin resistance indexes, high-sensitivity C-reactive protein, vitamin B12, folic acid and homocysteine. Statistical analysis was made using ANOVA, Student's t-test, Pearson's correlations and multiple linear regression. RESULTSː 93.9% of our population were women and mean age was 47.1±15.4 years. No significant differences were found between groups, regarding age, sex and body mass index (BMI). Homeostasis model assessment-insulin resistance (HOMA-IR) levels were significantly different in the three groups (p<0.001). In the total group, higher TSH values were associated to higher levels of triglycerides (r=0.206, p=0.002) and HOMA-IR (r=0.209, p=0.002), even after adjustment for age, sex and BMI. Thyroid peroxidase antibodies titers correlated positively with total cholesterol (r=0.166, p=0.013), LDL-cholesterol (r=0.173, p=0.010), ApoB (r=0.190, p=0.006) and HOMA-IR (r=0.141, p=0.033). Thyroglobulin antibodies correlated positively with triglycerides (r=0.140, p=0.036). CONCLUSIONSː HT patients with mild thyroid dysfunction present a more atherogenic lipid profile and higher resistance to insulin action. Therefore, screening for cardiovascular comorbidities in these patients is essential to provide an early diagnosis and better treatment decisions.

Choroba Hashimoto (Hashimoto's thyroiditis, HT) należy do grupy autoimmunizacyjnych chorób tarczycy (AITD). Rozwój HT związany jest z utratą tolerancji immunologicznej na własne antygeny tarczycy, co prowadzi do wnikania aktywowanych limfocytów do tkanki tego gruczołu i powoduje niszczenie komórek pęcherzykowych (tyreocytów). W efekcie dochodzi do spadku produkcji hormonów, czyli stanu niedoczynności tarczycy. HT charakteryzuje się obecnością w surowicy przeciwciał skierowanych przeciw własnym antygenom tarczycy, peroksydazie tarczycowej (TPO) i tyreoglobulinie (Tg). Przyczyną zniesienia tolerancji na własne antygeny i rozwoju choroby Hashimoto są czynniki genetyczne oraz środowiskowe. Zmiany zachodzące na poziomie molekularnym oraz konsekwencje funkcjonalne tych zmian są słabo poznane. Jednym z niezbadanych dotychczas aspektów tej choroby są zmiany w procesie glikozylacji białek. Celem przeprowadzonych badań była analiza strukturalna W-glikanów białek surowicy oraz ocena funkcjonalna zmian glikozylacji. Badania przeprowadzono na surowicy pacjentów z HT (grupa badana, n=51) i zdrowych dawców (grupa kontrolna, n=61) dobranych pod względem płci i wieku. Dawców z HT rekrutowano na podstawie podwyższonego miana przeciwciał anty-TPO i anty-Tg oraz obrazu USG tarczycy charakterystycznego dla AITD. Metodą wysokosprawnej chromatografii cieczowej (HPLC) wykonano ocenę ilościowych zmian zawartości struktur W-glikanów po deglikozylacji białek surowicy między grupą badaną i kontrolną. Metodą spektrometrii mas (MS) określono struktury W-glikanów białek surowicy. Sjalilację i fukozylację białek analizowano również metodą lektynową. Analiza MS wykazała, że frakcja W-glikanów, której zawartość istotnie statystycznie wzrasta w HT, zawiera dwie struktury kompleksowe: jednosjalowaną trzyantenową (A3G3S) oraz dwusjalowaną dwuantenową z fukozą antenową (FA2G2S2). W analizie z użyciem lektyn specyficznych dla fukozy i kwasu sjalowego (SA) stwierdzono istotny statystycznie spadek zawartości rdzeniowej fukozy oraz wzrost a2,3-sjalilacji białek w próbkach surowicy dawców z HT. Analizę funkcjonalną wykazanych w przebiegu HT zmian glikozylacji IgG wykonano na modelach in vitro cytotoksyczności komórkowej zależnej od przeciwciał (ADCC) i cytotoksyczności zależnej od dopełniacza (CDC). Komórkami docelowymi były ludzkie komórki pęcherzykowe tarczycy linii Nthy-ori 3-1 i komórki nowotworowe tarczycy linii FTC-133. Rolę komórek efektorowych w modelu ADCC spełniały komórki monojądrzaste krwi obwodowej (PBMC) zdrowych dawców oraz ludzkie komórki białaczki mieloidalnej linii HL-60. Komórki efektorowe były aktywowane przez przeciwciała klasy G (IgG) izolowane metodą chromatografii powinowactwa od zdrowych dawców i chorych z HT. Źródłem dopełniacza w modelu CDC była surowica pochodząca od zdrowych dawców. W celu oceny roli glikozylacji IgG na efektorowe funkcje przeciwciał cząsteczki IgG poddano działaniu neuraminidazy odcinającej SA od oligosacharydów. Wykazano zwiększoną lizę tyreocytów w obecności IgG od dawców z HT w porównaniu z kontrolą w obu modelach. Desjalilacja IgG nasilała intensywność ADCC oraz zmniejszała lizę w procesie CDC w HT w porównaniu do kontroli. Przeprowadzone badania wskazują, że w przebiegu choroby Hashimoto dochodzi do zmian sjalilacji białek surowicy. Zmieniona w HT glikozylacja IgG jest istotna w procesach niszczenia tyreocytów stanowiących jeden z elementów patologii tej choroby. Uzyskane wyniki stanowią wkład w zrozumienie procesów patologicznych zachodzących w chorobie Hashimoto.<br>Hashimoto's thyroiditis (HT) is an autoimmune disease characterized by chronic inflammation of thyroid gland. Most of HT patients produce antibodies against thyroid antigens, mainly thyroid peroxidase (TPO) and thyroglobulin (Tg). Anti-thyroid antibodies mediate an immune response which leads to tissue damage and a decrease of thyroid hormone synthesis named as hypothyroidism. One of the mechanism involved in thyroid damage in HT are antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). W-glycosylation of the Fc fragment affects the effector functions of IgG by enhancing or suppressing the cytotoxic effect. Glycosylation of serum proteins has been found to undergo changes during the progression of different diseases, with autoimmune disorders among them. Genetic and environmental factors are responsible for the breakdown of self-tolerance and the development of HT. Changes at the molecular level and the functional consequences of these alterations are poorly understood. Modifications of glycosylation process are one of the aspects of this disease that has been studied so far to a limited extent. The first aim of the study was to determine the glycosylation pattern of IgG-depleted sera from HT patients. Serum W-glycans were analysed by normal-phase high-performance liquid chromatography (NP-HPLC) and mass spectrometry (MS). Fucosylation and sialylation was also assayed by lectin blotting. Structural analysis of IgG-depleted serum W-glycome showed an increase of monosialylated tri-antennary structure (A3G3S1) and disialylated diantennary W-glycan with antennary fucose (FA2G2S2) in case of HT patients. Lectin blotting analysis demonstrated a significant decrease of Lens culinaris agglutinin (LCA) staining in HT samples, which resulted from the reduction of a1,6-linked core fucose. We also observed an increase of Maackia amurensis II lectin (MAL-II) reaction in HT due to the elevated level of a2,3-sialylation. Our recent study showed a decreased IgG core fucosylation in AITD patients compared to healthy volunteers. The second aim was to assess the impact of HT-specific IgG glycosylation on ADCC and CDC, using in vitro models. The normal thyroid Nthy-ori 3-1 cell line and thyroid carcinoma FTC-133 cells were used as the target cells. Peripheral blood mononuclear cells (PBMCs) from healthy donors and the HL-60 human promyelotic leukemia cell line served as the effector cells. IgG was isolated from sera of HT patients and healthy donors and then treated with a2-3,6,8-neuraminidase to cut off sialic acids (SA) from W-glycans. We observed more intensive cytotoxicity in the presence of IgG from HT patients than in the presence of IgG from healthy donors. Removal of SA from IgG W-glycans increased ADCC intensity and reduced CDC. The structural analysis of serum W-glycosylation confirmed that thyroid autoimmunity is accompanied by changes of serum protein sialylation. The detected alterations of serum protein sialylation might be caused by chronic inflammation in HT. The functional analysis completes our previous IgG W-glycosylation analysis in autoimmune thyroid patients. The results of functional tests confirmed that the enhanced thyrocyte lysis resulted from the higher anti-TPO content in the whole IgG pool of HT donors and showed that altered sialylation of IgG affects thyrocyte lysis in both cytotoxicity models. The obtained results demonstrated that the altered glycosylation is characteristic for thyroid autoimmunity and contribute to the understanding of pathological processes occurring in Hashimoto's disease.

Vitamin D deficiency and/or reduced function, as per certain polymorphisms of the vitamin D receptor (VDR) gene, have been related to several autoimmune disorders. The present study was aimed to investigate the association of Hashimoto's thyroiditis with vitamin D status and functional polymorphisms (SNPs) of the VDR gene. In this case-control study, 200 euthyroid subjects were enrolled: 100 newly diagnosed HT patients (87 F, 13 M; mean age ± SD 42 ± 15 year) and 100 healthy individuals, matched for age, sex, BMI, and month of blood sampling. Serum 25(OH)D3 was measured by HPLC. The VDR SNPs BsmI, ApaI, and TaqI, in strong linkage disequilibrium with each other, were detected by restriction fragment length polymorphism-PCR. The prevalence of vitamin D deficiency in HT patients was significantly higher than that in the control group (70 vs 18.2 %; p < 0.0001), and median serum 25(OH)D3 level was significantly lower in HT patients than controls (median value: 16.2 vs 37.4 ng/ml; p = 0.026). Moreover, there was a significant inverse correlation between serum 25(OH)D3 and TPOAb concentration (r = -0.669; p = 0.034). Contrarily, the genotype distribution of the studied SNPs was not different in the two groups (BsmI p = 0.783; ApaI p = 0.512; TaqI p = 0.471), as was the allelic frequency [f(B) p = 0.776, f(b) p = 0.887; f(A) p = 0.999, f(a) p = 0.999; f(T) p = 0.617; f(t) p = 0.617]. The present study first investigates newly diagnosed untreated HT and suggests that vitamin D deficiency may contribute to HT development and/or progression, acting as an environmental trigger, while the VDR locus does not appear to be involved in conditioning the genetic susceptibility to the disease, at least in Caucasians.

碩士<br>國立臺灣大學<br>臨床醫學研究所<br>103<br>Hashimoto’s thyroiditis (HT) is a common form of autoimmune thyroid disease (ATD), which affects up to 2–5 % of general population. It occurs 5–10 times more common in women than men. The annual incidence of HT worldwide is estimated to be 0.8–3.5 cases per 1000 persons. The incidence varies widely in different geographic locations depending on iodine content of diet and various environmental factors. ATD is the most frequent cause of hypothyroidism and goiter in countries where ordinary diet provides sufficient iodine. The three-quarters of subjects with HT have normal thyroid function at presentation, and 15–20% of subjects already have hypothyroidism. The euthyroid phase is often followed by a gradual development of subclinical hypothyroidism, which progress slowly to overt hypothyroidism. The prevalence of anti-thyroglobulin antibody (TA) in subjects with ATD is 25–50%, while 90–95% subjects has positive anti-thyroid peroxidase (TPO) antibody. High serum anti-TPO antibody concentrations predicted the progression of subclinical hypothyroidism to overt hypothyroidism. The anti-TPO antibody concentration is also closely associated with overt thyroid dysfunction, and their presence tends to correlate with thyroidal damage and lymphocyte infiltration. The presence of anti-thyroid autoantibody alone is associated with negative pregnancy outcomes, including placental abruption, gestational hypertension, preeclampsia, late abortion, fetal death, premature delivery, and neonatal respiratory distress. Although hypothyroid patients with ATD require levothyroxine replacement therapy, much less is known about benefits of any medical treatment in euthyroid patients with ATD. Hydroxychloroquine (HCQ) is an anti-malarial agent, and has been used as anti-rheumatic treatment in several autoimmune diseases. It is generally proposed that the mechanism of action of these anti-malarial agents as anti-rheumatic drugs results from their inhibition of antigen processing and presentation. This study is aimed to investigate the effect of HCQ treatment on serum anti-thyroid autoantibodies and thyroid functions in subjects with ATD. This is a retrospective chart review. A total of 97 subjects with HT having regular blood tests and follow-up at outpatient department were enrolled. Twenty-three of them having a six–month Plaquenil® treatment were defined as the treatment groups. The remained 74 subjects without experience of Plaquenil treatment were comprised as the non-treatment groups. ATD was diagnosed by positive serum anti-TPO antibody and/or positive TA concentrations. The differences in thyroid function and serum autoantibodies were compared between before, 3–month, and 6–month of Plaquenil treatment in the treatment group. The differences in thyroid function and serum autoantibodies were also compared between before and after Plaquenil treatment between the treatment and the non-treatment groups. In the present study, the majority of the study population was middle-aged women. The disease durations were 30.6 (6.8–93.4) and 39.1 (17.2–85.8) months in the treatment and the non-treatment group, respectively. The anti-TPO antibody concentration was significantly decreased after three–month of Plaquenil treatment, and continuously decreased after six–month of Plaquenil treatment (presented as median [interquartile range], 1162.80 [213.07–1607.90] IU/mL v.s. 541.65 [134.28–846.14] IU/mL v.s. 398.27 [109.95–636.23] IU/mL at baseline, 3–month, and 6–month, respectively, p<0.001). The TA titer was also decreased significantly at both third and sixth month of Plaquenil treatment comparing to the baseline (presented as median [interquartile range], 100.90 [24.26–397.80] IU/mL v.s. 54.78 [19.24–295.37] IU/mL v.s. 75.57 [19.50–258.93] IU/mL at baseline, 3–month, and 6–month, respectively, p<0.001). Compared the treatment group to the non-treatment group, the anti-TPO antibody concentrations were significantly reduced after Plaquenil treatment (presented as median [interquatile range], ΔTPO = -460.26 [-949.17– -65.36] IU/mL v.s. -8.91 [-131.82–22.66] IU/mL, adjusted p<0.001; TPO ratio = 0.49 [0.35–0.56] v.s. 0.92 [0.67–1.23], adjusted p=0.032; ΔTA = -16.82 [-89.23– -10.24] IU/mL v.s. 0.04 [-22.1–20.97] IU/mL, adjusted p=0.688; TA ratio = 0.62 [0.48–0.86] v.s. 1.00 [0.59–1.23], adjusted p=0.014). There was a significant increase in anti-TPO antibody concentrations twelve months after discontinuing Plaquenil treatment in the treatment group compared to the non-treatment group (presented as median [interquatile range], ΔTPO = 452.19 [35.41–772.07] IU/mL v.s. 0 [-48.19–80.93] IU/mL, adjusted p<0.001, TPO ratio = 1.84 [1.06–2.74] v.s. 1.00 [0.77–1.28], adjusted p=0.001). The study has shown that hydroxychloroquine treatment had significant effects in subjects with autoimmune thyroid disease. It significantly reduced the serum anti-TPO antibody and TA concentrations. However, we need further randomized control trial to evaluate its effects on goiter, subsequent thyroid hormone trends, serum inflammatory markers, and pregnancy complications.