Evidence of the Presence of Thyroid Hormones in Achatina fulica Snails

ABSTRACT The objective of this study was to identify thyroid hormones and to examine their putative site of synthesis in Achatina fulica snails. For this purpose, radioimmunoassays were performed for T3 and T4 before and after long starvation with or without hemolymph deproteinization. Sodium/iodide symporter activity in vivo was analyzed through 125I administration with and without KClO4 pretreatment. Only T4 was detected, and its concentration decreased due to starvation or deproteinization. However, high-performance liquid chromatography analysis also showed the presence of T2 and T3 apart from T4, but rT3 was not detected in the A. fulica hemolymph. The sodium/iodide symporter activity was greater in cerebral ganglia than digestive gland, but KClO4 treatment did not inhibit iodide uptake in any of the tissues analyzed. Altogether, our data confirm for the first time the presence of thyroid hormones in A. fulica snails and suggest their participation in the metabolism control in this species, although the putative site of hormone biosynthesis remains to be elucidated.

First Report of Familial Dysalbuminemic Hyperthyroxinemia With an ALB Variant

Familial dysalbuminemic hyperthyroxinemia (FDH) is an inherited disease characterized by increased circulating total thyroxine (T4) levels and normal physiological thyroid function. Heterozygous albumin gene (ALB) variants have been reported to be the underlying cause of FDH. To our knowledge, there have been no confirmed FDH cases in Korea. We recently observed a female patient with mild T4 elevation (1.2 to 1.4-fold) and variable levels of free T4 according to different assay methods. Upon Sanger sequencing of her ALB, a heterozygous c.725G>A (p.Arg242His) variant was identified. The patient's father and eldest son had similar thyroid function test results and were confirmed to have the same variant. Although the prevalence of FDH might be very low in the Korean population, clinical suspicion is important to avoid unnecessary evaluation and treatment.

Establishment of Trimester-Specific Reference Intervals for Thyroid Hormones in Korean Pregnant Women

BACKGROUND: Establishment of trimester- and assay-specific reference intervals for every population is recommended. The aim of this study was to establish a trimester- and assay-specific reference interval for thyroid-stimulating hormone (TSH) and free thyroxine (FT4) in Korean pregnant women. METHODS: From April 2012 to December 2012, 531 pregnant women receiving prenatal care and 238 age-matched, non-pregnant women were enrolled in this study. After excluding patients with pregnancy-associated complications or thyroid-specific autoantibody, 465 pregnant and 206 non-pregnant women were included. Non-parametric analysis (2.5-97.5th percentile) was performed to determine the reference interval. Levels of TSH and FT4 were determined by electrochemiluminescence immunoassay (Elecsys thyroid tests, Roche Diagnostics, Germany). RESULTS: The TSH reference intervals were 0.01-4.10, 0.01-4.26, and 0.15-4.57 mIU/L for the first, second, and third trimester, respectively. From the first trimester to the third trimester, the median TSH levels showed a significantly increasing trend (P<0.0001). The FT4 reference intervals were 0.83-1.65, 0.71-1.22, and 0.65-1.13 ng/dL for the first, second, and third trimester, respectively, showing a significantly decreasing trend (P<0.0001). CONCLUSIONS: Establishing trimester-specific reference intervals in pregnant women is essential for accurate assessment of thyroid function. Our population-specific and method-specific reference intervals will be useful for screening Korean pregnant women for thyroid disease.

Impact of hypothyroidism on the development of non-alcoholic fatty liver disease: A 4-year retrospective cohort study

BACKGROUND/AIMS: Hypothyroidism is reported to contribute to the development of nonalcoholic fatty liver disease (NAFLD). We compared the risk of the development of NAFLD among three groups with different thyroid hormonal statuses (control, subclinical hypothyroidism, and overt hypothyroidism) in a 4-year retrospective cohort of Korean subjects. METHODS: Apparently healthy Korean subjects without NAFLD and aged 20-65 years were recruited (n=18,544) at health checkups performed in 2008. Annual health checkups were applied to the cohort for 4 consecutive years until December 2012. Based on their initial serum-free thyroxine (fT4) and thyroid-stimulating hormone (TSH) levels, they were classified into control, subclinical hypothyroidism (TSH >4.2 mIU/L, normal fT4), and overt hypothyroidism (TSH >4.2 mIU/L, fT4 <0.97 ng/dL) groups. NAFLD was diagnosed on the basis of ultrasonography findings. RESULTS: NAFLD developed in 2,348 of the 18,544 subjects, representing an overall incidence of 12.7%: 12.8%, 11.0%, 12.7% in the control, subclinical hypothyroidism, and overt hypothyroidism groups, respectively. The incidence of NAFLD did not differ significantly with the baseline thyroid hormonal status, even after multivariate adjustment (subclinical hypothyroidism group: hazard ratio [HR]=0.965, 95% confidence interval [CI]=0.814-1.143, P=0.67; overt hypothyroidism group: HR=1.255, 95% CI=0.830-1.899, P=0.28). CONCLUSIONS: Our results suggest that the subclinical and overt types of hypothyroidism are not related to an increased incidence of NAFLD.

Excesso de Hormônio Tireoidiano em Curto Prazo Afeta o Coração, mas não Afeta a Atividade Adrenal em Ratos / Short-Term Thyroid Hormone Excess Affects the Heart but Does not Affect Adrenal Activity in Rats

Fundamento: O hipertireoidismo (Hi) exerce um amplo leque de influências em diversos parâmetros fisiológicos. Seu efeito perturbador sobre o sistema cardiovascular é um de seus impactos mais importantes. Além disso, o Hi foi clinicamente associado com o estresse induzido pela hiperativação do eixo hipotalâmico-pituitário-adrenal. Objetivo: Avaliar o impacto do Hi de curto prazo sobre o desempenho cardíaco e a atividade adrenal de ratos. Métodos: A indução de Hi em ratos Wistar através de injeções de T3 (150 μg/kg) por 10 dias (grupo com hipertireoidismo - GH) ou veículo (grupo controle). O desempenho cardiovascular foi avaliado por: ecocardiograma (ECO); razão peso do coração/peso corporal (mg/gr); contratilidade de músculos papilares isolados (MPI) e mensuração direta da pressão arterial. A atividade adrenal foi avaliada pela razão peso adrenal/ peso corporal (mg/gr) e níveis de 24 horas de corticosterona fecal (CF) no 1º, 5º e 10º dias de tratamento com T3. Resultados: No GH, o ECO mostrou redução dos Volumes Finais Sistólico e Diastólico, Tempos de Ejeção, Relaxamento Isovolumétrico e Diastólico Total, Áreas Sistólicas e Diastólica e razão E/A. Aumentaram a frequência cardíaca, a fração de ejeção e o débito cardíaco. A razão peso corporal/peso do coração foi maior. Da mesma forma, nos MPI, a taxa máxima de degradação da força durante o relaxamento foi maior em todas as concentrações extracelulares de cálcio. Os níveis de pressão arterial sistólica (PAS) foram maiores. (p ≤ 0,05). Por outro lado, não houve diferença na razão peso das adrenais/peso corporal ou níveis de 24 horas de CF. ...

Background: Hyperthyroidism (Hy) exerts a broad range of influences on a variety of physiological parameters. Its disruptive effect on cardiovascular system is one of its most remarkable impacts. Moreover, Hy has been clinically associated with stress - induced hyperactivation of the hypothalamic-pituitary-adrenal axis. Objective: Evaluate the impact of short-term Hy on cardiac performance and adrenal activity of rats. Methods: Induction of Hy in Wistar rats through injections of T3 (150 µg/kg) for 10 days (hyperthyroid group - HG) or vehicle (control group). The cardiovascular performance was evaluated by: echocardiography (ECHO); heart weight/body weight (mg/gr) ratio; contractility of isolated papillary muscles (IPM) and direct measurement of blood pressures. Adrenal activity was evaluated by adrenal weight/body weight (mg/gr) ratio and 24-hour fecal corticosterone (FC) levels on the, 5th and 10th days of T3 treatment. Results: In HG, the ECHO showed reduction of the End Systolic and End Diastolic Volumes, Ejection, Total Diastolic and Isovolumic Relaxation Times, Diastolic and Systolic Areas and E/A ratio. Heart Rate, Ejection Fraction and Cardiac Output increased. The heart weight/body weight ratio was higher. Similarly, in IPM, the maximum rate of force decay during relaxation was higher in all extracellular calcium concentrations. Systolic blood pressure (SBP) levels were higher. (p ≤ 0.05). On the other hand, there was no difference in the adrenal weight/body weight ratio or in the 24-hour FC levels. Conclusions: Hy induces positive inotropic, chronotropic and lusitropic effects on the heart by direct effects of T3 and increases SBP. Those alterations are not correlated with changes in the adrenal activity. .

Avaliação do perfil clínico e laboratorial de gatos hipertireoideos com ou sem lobo tireoidiano aumentado a palpação cervical / Clinical and laboratorial evaluation of hyperthyroid domestic cats with or without palpable thyroid gland

O hipertireoidismo é a endocrinopatia mais comum em gatos idosos. Devido à natureza progressiva da doença, a identificação de um estágio subclínico se torna essencial para melhor controle da doença. O presente estudo compreendeu um levantamento da frequência de gatos hipertireoideos durante o período de março de 2007 a abril de 2008, no estado do Rio de Janeiro. O objetivo deste trabalho foi avaliar os aspectos clínicos, laboratoriais e ecocardiográficos em uma população de gatos domésticos com hipertireoidismo naturalmente adquirido, com ou sem lobo tireoidiano palpável. A seleção dos animais foi realizada através da detecção do valor de tiroxina (T4) total acima dos valores de referência com a técnica de radioimunoensaio. Os animais foram divididos em dois grupos com base na identificação do aumento da tireoide à palpação: Grupo I (tireoide não palpável) e Grupo II (tireoide palpável). Avaliações clínica e laboratoriais completas foram realizadas em todos os gatos do estudo. A avaliação clínica incluiu avaliação comportamental, peso, escore de condição corporal, pele e pelagem, auscultação cardiopulmonar, palpação tireoidiana e aferição da pressão arterial sistólica. Além do T4 total, os seguintes exames laboratoriais foram realizados: hemograma, ureia, creatinina, alanina aminotransferase (ALT), fosfatase alcalina (FA) e glicose. Trinta e um animais foram submetidos à avaliação cardíaca, através de ecocardiograma. Dos 178 animais avaliados, 51 foram incluídos nesse estudo por apresentarem aumento sérico da T4. Vinte e seis animais foram inclusos no Grupo I e vinte e cinco no Grupo II. Os parâmetros clínicos, laboratoriais e ecocardiográficos foram muito semelhantes entre os dois grupos. No entanto, os níveis séricos de T4 total foram significativamente menores nos gatos com tireoide não palpável. Todo gato acima de sete anos deve ser avaliado para presença de hipertireoidismo através da palpação tireoidiana e avaliação sérica de tiroxina total, pois muitos gatos sem sinais clínicos apresentam hipertireoidismo e o diagnóstico precoce permite diminuir os efeitos sistêmicos da doença em órgãos como fígado, rins e coração.

Hyperthyroidism is the most common endocrine disorder of older cats. Due to the progressive nature of the disease, the identification of a subclinical stage is essential in order to have a better control of the disease. The present study was a survey of the frequency of feline hyperthyroidism in Rio de Janeiro, from March, 2007 to April, 2008. The purpose of this study was to perform an evaluation of the clinical, laboratorial and echocardiographic aspects in a feline population of naturally acquired hyperthyroidism, with or without palpable thyroid gland. The selection of the cats was done by the documentation of an elevation of total thyroxine (TT4) levels by radioimmunoassay. The animals were divided in two groups according to the thyroid palpation: group I (non-palpable thyroid lobe) and group II (palpable thyroid lobe). Laboratorial and complete clinical evaluations were performed in all cats. The clinical evaluation included behavioral evaluation, body weight, body condition, dermatologic, cardiopulmonary auscultation, thyroid palpation and systolic blood pressure reading. Besides the TT4, the following exams were performed: urea, creatinine, alanine aminotransferase (ALT), alkaline phosphatase (ALP) and glucose. Thirty one cats had an echocardiogram performed. On the basis of TT4 concentrations, 51 of the 178 cats were classified as hyperthyroid. One or more enlarged thyroid glands were palpated in 25 of the 51 hyperthyroid cats and were included at Group II. Twenty six cats didn't palpable thyroid gland and were included at Group I. Clinical, laboratorial and echocardiographic parameters were similar between the two groups. However, the TT4 levels were significantly lower in the non-palpable thyroid group. All geriatric cats must be thyroid gland palpable on clinic examination and have TT4 measured. Many hyperthyroid cats may be asymptomatic and early diagnosis prevents organ damage such as liver, kidneys and heart.

Haematological and biochemical parameters in Churra-da-Terra-Quente ewes from the northeast of Portugal / Parâmetros hematológicos e bioquímicos de ovelhas da raça Churra da Terra Quente do nordeste de Portugal

Hematological and biochemical parameters, including plasma electrolytes and thyroid hormones, were determined in 73 clinically healthy Churra-da-Terra-Quente ewes, a typical breed from the northeast of Portugal. The hemogram values were: erythrocytes 9.8±1.5×10(12)/L; haemoglobin 118.1±19.1g/L; haematocrit 40.8±5.9 percent; leukocytes 5.7±1.8×10(9)/L; and platelets 544.3±177.2×10(9)/L. The thrombin time was 17.3±1.7 seconds. The values of biochemical parameters were: total protein 76.4±6.1g/L; glucose 2.87±0.60mmol/L; total cholesterol 1.65±0.33mmol/L; aspartate aminotransferase 155.9±49.2U/L; alanine aminotransferase 23.2±9.6U/L; γ-glutamyl transferase 48.0±18.7U/L; total alkaline phosphatase 121.6±76.1U/L; glutamate dehydrogenase 6.4±3.7U/L; urea 7.32±2.22mmol/L; creatinine 123.0±54.1μmol/L; total calcium 2.53±0.25mmol/L; phosphorus 2.10±0.46mmol/L; magnesium 1.01±0.09mmol/L; sodium 152.04±3.65mmol/L; potassium 4.7±0.4mmol/L; ionized calcium 1.32±0.07mmol/L; total thyroxine 111.75±42.29nmol/L; total triiodothyronine 1.01±0.28nmol/L; free T4 11.93±1.78pmol/L; free T3 4.22±1.33pmol/L; and thyroid-stimulating hormone 0.18±0.19μIU/mL. Although differences among the Churra-da-Terra-Quente breed and other breeds may occur, the hematological and biochemical parameters, plasma electrolytes, and thyroid hormones, for this indigenous breed, were generally situated within the reference intervals previously reported for sheep.

Os valores hematológicos e bioquímicos, incluindo os eletrólitos plasmáticos e os hormônios da tireoide, foram determinados em 73 ovelhas, clinicamente saudáveis, da raça Churra da Terra Quente, raça ovina característica do nordeste de Portugal. Os valores obtidos para o hemograma foram: eritrócitos 9,8±1,5×10(12) /L; hemoglobina 118,1±19,1g/L; hematócrito 40,8±5,9 por cento; leucócitos 5,7±1,8×10(9) /L e plaquetas 544,3±177,2×10(9)/L. O tempo de trombina foi de 17,3±1,7 segundos. Os valores dos parâmetros bioquímicos avaliados foram: proteínas totais 76,4±6,1g/L; glicose 2,87±0,60mmol/L; colesterol total 1,65±0,33mmol/L; aspartato amino transferase 155,9±49,2U/L; alanina amino transferase 23,2±9,6U/L; gama-glutamil transferase 48,0±18,7U/L; fosfatase alcalina total 121,6±76,1U/L; glutamato desidrogenase 6,4±3,7U/L; ureia 7,32±2,22mmol/L; creatinina 123,0±54,1μmol/L; cálcio total 2,53±0,25mmol/L; fósforo 2,10±0,46mmol/L e magnésio 1,01±0,09mmol/L; sódio 152,04±3,65mmol/L; potássio 4,7±0,4mmol/L e cálcio ionizado 1,32±0,07mmol/L; tiroxina total 111,75±42,29nmol/L; tri-iodotironina total 1,01±0,28nmol/L; T4 livre 11,93±1,78pmol/L; T3 livre 4,22±1,33pmol/L e hormônio estimulante da tireoide 0,18±0,19μIU/mL. Apesar de terem sido observadas algumas diferenças entre a raça Churra da Terra Quente e outras raças, os valores hematológicos e bioquímicos, eletrólitos plasmáticos e hormônios da tireóide, desta raça autóctone apresentam-se no geral situados dentro dos intervalos de referência publicados para a espécie ovina.

Nitric oxide contributes to learning and memory deficits observed in hypothyroid rats during neonatal and juvenile growth

INTRODUCTION: Severe cognitive impairment follows thyroid hormone deficiency during the neonatal period. The role of nitric oxide (NO) in learning and memory has been widely investigated. METHODS: This study aimed to investigate the effect of hypothyroidism during neonatal and juvenile periods on NO metabolites in the hippocampi of rats and on learning and memory. Animals were divided into two groups and treated for 60 days from the first day of lactation. The control group received regular water, whereas animals in a separate group were given water supplemented with 0.03 percent methimazole to induce hypothyroidism. Male offspring were selected and tested in the Morris water maze. Samples of blood were collected to measure the metabolites of NO, NO2, NO3 and thyroxine. The animals were then sacrificed, and their hippocampi were removed to measure the tissue concentrations of NO2 and NO3. DISCUSSION: Compared to the control group's offspring, serum thyroxine levels in the methimazole group's offspring were significantly lower (P<0.01). In addition, the swim distance and time latency were significantly higher in the methimazole group (P<0.001), and the time spent by this group in the target quadrant (Q1) during the probe trial was significantly lower (P<0.001). There was no significant difference in the plasma levels of NO metabolites between the two groups; however, significantly higher NO metabolite levels in the hippocampi of the methimazole group were observed compared to controls (P<0.05). CONCLUSION: These results suggest that the increased NO level in the hippocampus may play a role in the learning and memory deficits observed in childhood hypothyroidism; however, the precise underlying mechanism(s) remains to be elucidated.

Hypothyroid associated polyneuropathy in dogs: report of six cases / Polineuropatia associada a hipotireoidismo em cães: relato de seis casos

Six Doberman Pinscher, between six and eight years of age, were presented to the Veterinary Hospital from Faculty of Veterinary Science of The University of Buenos Aires. Neurological examination revealed tetraparesis with inability to walk, decreased muscle tonus and myotatic reflexes in all dogs. Serum cholesterol levels, creatine kinase and alkaline phosphatase activities were mildly to markedly elevated, and tibial motor nerve conduction velocities were slow in all dogs. Basal measurements of free T4 and TSH were determined by radioimmunoassay. Although fT4 values were within normal range, in all dogs TSH values were elevated. Based on this results, hypothyroidism was diagnosed and a supplementation therapy was established with oral levothyroxine (T4). Two weeks after treatment has been started, all patients had an improvement in clinical signs, and within a month gait became normal, as well as muscular tonus and spinal reflexes.

Seis Dobermans Pinscher, entre seis e oito anos de idade, foram encaminhados ao Hospital Veterinário da Faculdade de Ciências Veterinárias da Universidade de Buenos Aires. O exame neurológico revelou tetraparesia com incapacidade para andar, diminuição do tono muscular e de reflexos miotáticos em todos os cães. Os níveis de colesterol, creatina quinase e fosfatase alcalina encontravam-se de moderada a acentuadamente elevados. As velocidades de condução nervosa do nervo tibial estavam diminuídas em todos os cães. Os níveis séricos basais de T4 livre e TSH foram determinados por radioimunoensaio e, embora os valores de T4 livre estivessem dentro dos limites de normalidade, em todos os cães o TSH estava elevado. Baseado nestes resultados, diagnosticou-se hipotireoidismo e iniciou-se uma suplementação oral com levotiroxina (T4). Duas semanas após o início do tratamento todos os pacientes tiveram melhora clínica e, dentro de um mês a locomoção, o tono muscular e os reflexos medulares tornaram-se normais.

Thyroid function in beta-thalassemic children receiving hypertransfusions with suboptimal iron-chelating therapy.

A cross-sectional study of thyroid function, free thyroxine (FT) and thyrotropin (TSH) concentrations, was carried out in 51 transfusion-dependent beta-thalassemic patients receiving suboptimal iron-chelating therapy. Nine patients had normal FT4 levels with elevated TSH levels (5.9-15.6 mLU/L), consistent with the diagnosis of compensated primary hypothyroidism and giving a prevalence of abnormal thyroid function of 17.6%. All patients with abnormal thyroid function had negative thyroid antibodies. No particular risk factor for abnormal thyroid function could be identified. Of the nine patients with compensated primary hypothyroidism, one patient showed a further increase in TSH level after 1 year of follow-up. The results of the present study emphasize the importance of thyroid function monitoring in hypertransfused beta-thalassemic patients.

Management of low-risk patients with thyroid carcinoma and detectable thyroglobulin on T4 after thyroidectomy and ablation with iodine-131

OBJECTIVE: To evaluate the positive predictive value of detectable Tg during T4 therapy (Tg on T4) in patients with thyroid cancer after total thyroidectomy and remnant ablation, discussing the work-up in this situation and the empirical indication of 131I. PATIENTS AND METHODS: Initially, 234 low-risk patients [tumor < 5cm, completely resected, no extensive extrathyroid invasion (pT4)] submitted to total thyroidectomy and ablation with 131I (3.7­5.5 GBq) who presented no ectopic uptake on RxWBS were studied. Of these, 23 patients with detectable Tg on T4 (> 1ng/ml) during the first year after initial therapy were selected. RESULTS: Metastases were detected by neck US in 7 patients, by chest CT in 2 and by US and CT in 3. Four of five patients with lung metastases upon CT had a positive RxWBS. Eleven patients with negative US and CT received a new 131I dose (without DxWBS), and RxWBS showed ectopic uptake in 3 patients. Among the patients with negative RxWBS, 7 remained free of apparent disease and Tg was declining (5 with undetectable Tg on T4 at the end of the study). One patient presented an increase in Tg and FDG-PET was positive for lymph node and bone metastases. CONCLUSIONS: All patients with Tg on T4 > 5ng/ml presented apparent disease. In these cases, even when US and CT are negative, the administration of a therapeutic dose of 131I (without DxWBS) and FDG-PET are recommended. Among patients with detectable Tg on T4 < 5ng/ml and negative US and CT, only 12 percent presented ectopic uptake on RxWBS. These cases could be followed up by monitoring Tg on T4, and RxWBS and FDG-PET should only be performed if this marker does not decrease after 1­2 years.

OBJETIVO: Avaliar o valor preditivo positivo da Tg detectável durante terapia com T4 (Tg sob T4) em pacientes com câncer de tireóide após tireoidectomia total e ablação dos remanescentes, discutindo o manuseio dessa situação e a indicação empírica de 131I. PACIENTES E MÉTODOS: Inicialmente, foram estudados 234 pacientes de baixo risco [tumor < 5cm, completamente ressecado, sem invasão extratireoideana extensa (pT4)] submetidos à tireoidectomia total e ablação com 131I (3,7­5,5 GBq) que não apresentaram captação ectópica com RxWBS. Desses, foram selecionados 23 pacientes com Tg detectável com T4 (> 1ng/ml) durante o primeiro ano após a terapia inicial. RESULTADOS: Metástases foram detectadas em 7 pacientes pelo US cervical, em 2 pela TC de tórax e em 3 pela US e TC. Quatro de 5 pacientes com metástases pulmonares à TC tiveram um RxWBS positivo; 11 pacientes com US e TC negativos receberam uma nova dose de 131I (sem DxWBS), e a RxWBS mostrou captação ectópica em 3 pacientes. Entre os pacientes com RxWBS negativo, 7 permaneceram livres de doença aparente e a Tg estava em declínio (5 com Tg indetectável sob T4 ao final do estudo). Um paciente apresentou aumento da Tg e o FDG-PET foi positivo para linfonodos e metástases ósseas. CONCLUSÕES: Todos os patients com Tg sob T4 > 5ng/ml apresentaram doença aparente. Nesses casos, mesmo quando a US e a TC são negativos, é recomendada a administração de dose terapêutica de 131I (sem DxWBS) e FDG-PET. Em pacientes com Tg detectável sob T4 < 5ng/ml, mas US e TC negativos, apenas 12 por cento apresentaram captação ectópica com a RxWBS. Estes casos podem ser seguidos pelo monitoramento da Tg sob T4, e RxWBS e FDG-PET devem ser feitos apenas se esse marcador não diminuir.

Cinco diferentes tipos de imágenes gammagráficas tiroideas en pacientes con enfermedad de Graves tratados con 131I en el Paraguay / Five different gammagraphic images of thyroid gland in patients with Grave’s disease treated with 131I in Paraguay

Thyroid disease is frequent in Paraguay, a country with a prevalence of goiter 48,6 percent in general population located in the center of South America. Grave’s disease constitutes the most common thyroid hyperfunction observed whose treatment can be carried out with medication (propiltiouracil, metimazol, etc.), surgery or iodine 131(131I) We analyzed 70 patients this type of hyperthyroidism treated with the 131I, in its clinical aspect pre and post treatment, ultrasound and nuclear scan findings of the gland thyroid, the hormonal respond Ft4, T3, TSH, thyroid antibodies TPOab, TGab, TRab. Besides the diffuse classic image observed in the thyroid scan and by ultrasonography of the gland, in Grave’s disease, 4 types of images were identified with nodules (multinodular, hot nodule, cold nodule and miliar). The group with diffuse increase in size form was the most numerous (50 percent) continued by the variety multinodular (30 percent), Marin-Lenhart’s Sx (hot nodule) 14 percent, miliary 3 percent, and cold nodule 3 percent. Three months after the treatment with the radioiodine was observed the decrease of the size and thyroid volume in 68 percent of the patients, thyroid uptake with 131I diminished in 75 percent. All patients had an increase of weight of 20 percent and 87 percent of then were feminine. The signs and symptoms were normalized in 88,5 percent of the patients. The levels of FT4 were normalized in 73, 8 percent, T3 in 66 percent, TSH in 47,7 percent, TPOab in 83 percent, TGab in 90 percent, and TRab in 84 percent. A received a single dose of 131I was used it in 93 percent of the patient The cost of the 131I in the Clinic Hospital was half of the cost of the surgery, and at private level the fourth part but cheap.

High pressure liquid chormatography determination of the concentration and integrity of L-thyroxine in free T4 stock solution

Characterization studies were designed to evaluate the concentration and integrity of the L-thyroxine (T4) molecule (3,5,3',5'-tetraiodothyronine) in the free T4 stock solution (FT4SS) (code 99544). The determination of the concentration of T4 in FT4SS is critical to ensure that the free T4 calibrators and controls are manufactured with the least number of adjustments possible. The most significant conclusions drawn from these characterization studies are the following: (1) An accurate and sensitive HPLC method has been developed to measure the T4 concentration in FT4SS. The root cause of the failure of FT4SS to pass retest/ review is the presence of an unknown T4 degradation product with significantly higher molar extinction coefficient at 230 nm than T4 itself. The L-thyroxine concentration reference comparison spectrophotometric test with the current 43 to 58 ug/ml specification range (as per scp.99544, ed. 13A) is adequate to monitor the generation of the unknown T4 degradation product. The characterized T4 degradation product is not 3,5,3'-triiodo-thyronine (T3) and it is suspected that the identity of the degradation product is reverse T3 (3,3',5'-triiodothyronine). The use of sodium l-thyroxine pentahydrate (Na- T4-5H2O) as the equivalent of T4 (free base) is adequate provided that an excess of 15over the desired amount of T4 is weighed.

Tireoidite de Hashimoto / Hashimoto thyroiditis

Com a melhora no controle e tratamento de doenças infecciosas, as doenças auto-imunes começam a adquirir uma importância cada vez maior na faixa etária pediátrica e na adolescência e devem ser reconhecidas pelos pediatras. Neste sentido, a tireoidite linfocitária crônica ou tireoidite de Hashimoto(TH)...

Healthy population; reference values of thyroid hormones

The reference values of thyroid hormones in healthy population of Multan area were determined at Combined Military Hospital Multan. A total of 295 subjects comprising 105 adult males aged 18-50 years, 72 adult females [non pregnant] aged 16-45 years, 65 adult females [pregnant] aged 21-35 years and 53 newborns were included in the study. Serum TSH, total T4, total T3, free T4 and free t[number] were analyzed by enzymatic immunoassay on semi-automatic analyser [Serozyme-1] of Serono-USA. The reference values were calculated using 2.5 and 97.5 percentiles as lower and upper limits [95%]. In adult males, the reference values of TSH was 0.4 -6.0 IU/L and T$ was 52 - 180 nmol/l, total T3 was 1.1 - 2.9 nmol/l, free T4 was 8.2 - 24 pmol/l and free T3 was 1.5 - 7.3 pmol/l. In adult females [non pregnant], the values of the analytes were almost same as in adult males. In adult females [pregnant] the values of total T4 and T3 were significantly higher than adult males. In newborns the levels of TSH were significantly higher and level of other parameters moderately higher than adult males. It is recommended that reference values of thyroid hormones should be established in various areas of Pakistan by the concerned laboratories to make appropriate use of such investigations

Tamizaje del hipotiroidismo congénito en Guatemala: Incidencia durante los primeros diez años. Valores de hormona estimulante del tiroides y tiroxina en neonatos / Screening for congenital hypothyroidism in Guatemala

Objetivo: Reportar la incidencia de hipotiroidismo congénito(HC) en un programa de tamizaje neonatal.Reportar valores de referencia de tirotropina y tiroxina en neonatos guatemaltecos urbanos. Diseño:Estudio prospectivo, longitudinal.Programa de tamizaje neonatal. Análisis retrospectivo.Contexto:Unidad de Neonatología,Departamento de Pediatría del Hospital General San Juan Dios de Guatemala. Metodología: A todo recién nacido a su egreso del hospital, se le tomó una muestra de 6 gotas de sangre venosa del dorso de la mano, depositada en papel filtro. Análisis de TSH Y T4 por RIA. Los casos con TSH>40 UI/ml, T4 menor de 4.5 Hg/dl se consideraron sospechosos, se corroboró el dato ena nueva muestra del papel filtro. Si se repitió un nivel anormal, se citó al caso y se confirmó o descartó el hipotiroidismo congénito midiendo TSH y T4 en nueva muestra de suero.Edad gestacional, peso al nacer y sexo del caso estudiado fueron anotados en el mismo papel filtro.Resultados: Se evaluaron 28067 muestras de 80734 recién nacidos. Se detectó 16 casos nuevos de HC por el programa y 14 por la clínica de endocrinología.La incidencia promedio de HC fue de 1:1754. Consideramos que no hubo diferencias en los valores de TSH al agrupar por peso al nacer, si en los valores de T4.La edad gestacional si influyó en los valores de TSH.Conclusión: El hipotiroidismo congénito fue una entidad frecuente en neonatos de nuestro Hospital. La incidencia es alta (3 veces) comparada con la de los países desarrollados. Debe continuarse el tamizaje y mejorar las tasas de cobertura.

Anticuerpos abtitiroideos en madres de recien nacidos con TSh elevada transitoria y de hipotiroideos congenitos / Antithyroid antibodies in mothers of newborns with elevated transient TSH and of congenital hypothyroid infants

La función de los anticuerpos tiroideos maternos en el desarrollo de la TSH elevada transitoria (tr-HTSH) en el recién nacido y/o el hipotiroidismo congénito (CH) ha sido sugerido por varios autores, pero aún es motivo de discusión. Con el propósito de conocer la presencia en las madres de anticuerpos antitiroideos convencionales y su relación con HTSH-tr y CH, se estudiaron 563 madres en el período posparto en 3 grupos: I. 235 madres de recién nacidos con TSH elevada (> 25 mU/L) en muestra de suero del cordón umbilical (screening). II. 48 madres de niños con hipotiroidismo congénito (una madre con antireosis). III (grupo control). 280 madres de niños con TSH normal en muestra de suero del cordón. La frecuencia de Mab fue de 4,8 porciento (11/228) en el grupo I, 6,2 porciento (3/48) en el grupo II y 5,5 porciento (15/274) en el grupo III, sin diferencias significativas entre los grupos. Resultados similares se encontró para los Tab: 2,2 porciento (5/227), 0 porciento (0/48) y 0,4 porciento (1/271) en los grupos I, II y III; y para los TPO: 4,5 porciento (10/223), 2,2 porciento (1/48) y 3,2 porciento (8/253). No se encontraron diferencias significativas en la frecuencia de bocio y los valores medios de TSH y T4 en los diferentes grupos. En conclusión, la presencia materna de los anticuerpos antitiroideos estudiados (Mab, Tab y TPO) no desempeñan una función importante en la génesis de tr-HTSH o CH en el recién nacido

Effects of estradiol benzoate on 5'-iodothyronine deiodinase activities in female rat anterior pituitary gland, liver and thyroid gland

There is little information on the possible effects of estrogen on the activity of 5'-deiodinase (5'-ID), an enzyme responsible for the generation of T3, the biologically active thyroid hormone. In the present study, anterior pituitary sonicates or hepatic and thyroid microsomes from ovariectomized (OVX) rats treated or not with estradiol benzoate (EB, 0.7 or 14 mug/100 g body weight, sc, for 10 days) were assayed for type I 5'-ID (5'-ID-I) and type II 5'-ID (5'-ID-II, only in pituitary) activities. The 5'-ID activity was evaluated by the release of (125)I from deiodinated (125)I rT3, using specific assay conditions for type I or type II. Serum TSH and free T3 and free T4 were measured by radioimmunoassay. OVX alone induced a reduction in pituitary 5'-ID-I (control = 723.7 + 67.9 vs OVX = 413.9 + 26.9; P<0.05), while the EB-treated OVX group showed activity similar to that of the normal group. Thyroid 5'-ID-I showed the same pattern of changes, but these changes were not statistically significant. Pituitary and hepatic 5'-ID-II did not show major alterations. The treatment with the higher EB dose (14 mug), contrary to the results obtained with the lower dose, had no effect on the reduced pituitary 5'-ID-I of OVX rats. However, it induced an imporatnt increment of 5'-ID-I in the thyroid gland (0.8 times higher than that of the normal group: control = 131.9 + 23.7 vs OVX + EB 14 mug = 248.0 + 31.2; P<0.05), which is associated with increased serum TSH (0.6-fold vs OVX, P<0.05) but normal serum free T3 and free T4. The data suggest that estrogen is a physiological stimulator of anterior pituitary 5'-ID-I and a potent stimulator of the thyroid enzyme when employed at high doses.

Hormona Tiroidea (T3-T4) en Leche Materna / Tyroid hormone (T3-T4) in maternal milk

En nuestro pais esta prohibido que las madres que ingieren hormonas tiroidea lacten a sus hijos, por su posible repercusion sobre el recien nacido. Observaciones recientes han puesto en duda la necesidad de tal restriccion. Por ello se estudiaron 20 mujeres en los primeros 10 dias del posparto (grupo 1) y 15 entre los 15 y 60 dias (grupo 3) y 20 que ingerian esta hormona en dosis sustitutiva - 120 mg tiroides desecado, 100 g de 1-T4 o 1 tableta de liolevo B- en los primeros 10 dias del posparto (grupo 2) y 15 entre los 15-60 dias (grupo 4). La leche se obtuvo por medio manual o mecanico. Se determinaron T4t y T3r por RIA, previa separacion de la grasa. La ingestion diaria de leche del recien nacido se calculo sobre la base de 400-1 000 mL/dia para los grupos 1 y 2 y de 700 a 1 200 mL/dia para los grupos 3 y 4. Se tomaron como valores de referencia inferiores los limites de sensibilidad del metodo: 0,5 g/dL para T4t y 0,01 g/dL para T3t (cv:10 por ciento y 8m por ciento, respectivamente). La dosis sustitutiva, necesaria para revertir el hipotiroidismo neonatal, es de 10 g/kg/dL de T4 y de 5 g/kg/dL de T3. Se aplico la t de student para 2 muestras independientes. Grupo 1. Concentracion de T4: x < 0,5 g/dL y de T3: x = 0.015 +/- 0,004 g/dL. (0,013-0,032). El RN ingeriria: T4 de 2 a 5 g/d y Te de 0,052 a 0,32 g/d. Grupo 2. Concentracion de T4 : x < 0,5 g/dL y de T3: x= 0,04 +/- 0,21 g/dL (0,013 +/- 0,097). Estos RN ingeririan igual T4 y T3 de 0,052-0,97 g/d. NO se constaron diferencias significativas (p <0,05) entre ambos grupos. Grupo 3. Concentracion de T4: x= 0,52 +/- 0,04 g/dL (0,5-0,64) y de T3: x,0,093 +/- 0,04 g/dL (0,013-0,16). Los ninos tomarian: T4 de 3,5 a 7,7 g/d y T3: 0.091 a 3,5 g/d. Grupo 4. Concentracion de T4: x 0,64 +/- 0,17 g/dL (0,5-1,05) y de T3: x 0,082 +/- 0,058 g/dL (=,013-0,17). La ingestion en estos RN seria de T4: 3,5 a 12,8 g/d y de T3:0,091 a 2,88 g/d. No se constataron diferencias significativas entre estos 2 ultimos grupos asi como tampoco con los grupos 1 y 2 (p < 0,05). Las madres que toman las hormonas tiroidea en dosis sustitutivaa si pueden lactar, por lo tanto, se puede quitar la prohibicion