RESUMO
OBJECTIVES: Children on long-term parenteral nutrition (PN) are at high risk of iodine deficiency (ID). However, most available information comes from cross-sectional studies. We investigated the iodine status, associated factors, and prevalence of hypothyroidism in children with intestinal failure (IF) who were followed up longitudinally. METHODS: This was a cohort study of children with IF monitored for urine iodine concentration (UIC), iodine intake, serum selenium concentration, and thyroid function in an intestinal rehabilitation program. The outcome variable ID was defined as a UIC value < 100 µg/L. Adjusted generalized estimating equations were used to assess the effects of the exposure variables on the UIC. RESULTS: Twenty-four patients aged 62.7 (39.1; 79.7) months who received PN for 46.5 (21.5) months were included. The average energy supply was 81.2 kcal/kg/day, 77.6% of which was provided by PN. An average of 5.2 UIC measurements per patient were performed. ID prevalence decreased from baseline (83.3%) to the last assessment (45.8%). Three patients had hypothyroidism secondary to iodine and selenium combined severe deficiency. Iodine intake from enteral or oral nutritional formulas was positively associated with UIC (ß = 0.71 [0.35, 1.07]; p < 0.001). Meeting approximately 80% of the estimated average requirement for iodine from nutritional formulas resulted in a greater probability of normal UIC values. CONCLUSION: ID is highly prevalent in children with IF who receive long-term PN and its frequency decreases with iodine intake from nutritional formulas. Severe combined iodine and selenium deficiencies are associated with the development of hypothyroidism in these patients.
Assuntos
Hipotireoidismo , Insuficiência Intestinal , Iodo , Desnutrição , Selênio , Criança , Humanos , Estudos de Coortes , Estudos Transversais , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia , Estado NutricionalRESUMO
OBJECTIVE: The use of parenteral nutrition (PN) formulations that do not contain iodine can contribute to the deficiency of this mineral, potentially leading to hypothyroidism and, ultimately, neurocognitive impairments. This study aimed to evaluate TSH alterations in newborns receiving PN. METHODS: Retrospective study of neonatal intensive care unit patients receiving PN for > 15 days. Nutritional, anthropometric, and biochemical variables (TSH, T4, CRP) were analyzed. Hypothyroidism was defined by TSH > 10 mU/L. RESULTS: Two hundred newborns were evaluated [156 (78%) preterm, 31±5 weeks of gestational age, 112 (56%) with very or extremely low birth weight]. The median (IQR) hospital stay was 68 (42-110) days, PN duration was 31 (21-47) days, and 188 (94%) patients also received enteral nutrition. Overall, 143 (71.5%) newborns underwent at least one TSH measurement. The prevalence of hypothyroidism was 10.5%. The Median PN duration in this group was 51 (34-109) days. Among those with hypothyroidism, 10 received Lugol's solution and six levothyroxine. Thirteen patients received prophylactic Lugol's solution with a median PN duration of 63 (48-197) days. TSH levels correlated positively with PN duration (r = 0.19, p = .02). CONCLUSIONS: The present data suggest that changes in TSH and T4 levels are present in neonates receiving PN for > 15 days, suggesting this population may be at risk for developing hypothyroidism. Therefore, the authors suggest that TSH and T4 measurements should be included as routine in neonatal patients receiving PN for > 15 days if PN formulations are not supplemented with iodine, and that iodine supplementation be provided as necessary.
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Hipotireoidismo , Iodo , Humanos , Recém-Nascido , Hipotireoidismo/epidemiologia , Hipotireoidismo/etiologia , Unidades de Terapia Intensiva Neonatal , Nutrição Parenteral/efeitos adversos , Prevalência , Estudos Retrospectivos , TireotropinaRESUMO
Introducción: El hipotiroidismo es la insuficiente producción de hormona tiroidea, para satisfacer las necesidades corporales. Este puede ser primario (con pérdida de la función de la glándula tiroidea) o secundario (por falta de estimulación de la glándula). Dada la alta prevalencia del hipotiroidismo, y frecuentes asociaciones con otras enfermedades, se realizó una revisión que puntualiza aspectos de interés clínico en esta patología, que pueden resultar útiles en la práctica médica. Metodología: Se efectuó una búsqueda bibliográfica en PubMed, PubMed Central, MEDLINE Complete, Epistemonikos, Europe PMC y Scielo. Se buscaron los términos "hipotiroidismo" y "tiroides", y se acortaron los artículos a los últimos 5 años. Resultados: Se incluyeron en total 36 artículos publicados en Inglés y en Español. Se seleccionaron aquellos relacionados al hipotiroidismo que exponen asociaciones con otras patologías. Entre estas patologías se encuentra la diabetes, las dislipidemias, enfermedades cardiovasculares, hepáticas, entre otras. Conclusiones: El hipotiroidismo es una patología prevalente que se asocia de forma frecuente con muchas otras comorbilidades que hay que tener en cuenta a la hora de abordar estos pacientes, y con ello tomar las mejores decisiones diagnósticas y terapéuticas.
Introduction: Hypothyroidism is the insufficient production of thyroid hormone to meet the bodily needs. This can be primary (with loss of function of the thyroid glands) or secondary (due to lack of stimulation of the glands). Given the high prevalence of hypothyroidism, and frequent associations with other diseases, a review was carried out that points out aspects of clinical interest in this pathology, which may be useful in medical practice. Methodology: A bibliographic search was carried out in PubMed, PubMed Central, MEDLINE Complete, Epistemonikos, Europe PMC and Scielo. The terms "hypothyroidism" and "thyroid" were searched, and the articles were shortened to the last 5 years. Results: A total of 36 articles published in English and Spanish were included. Those related to hypothyroidism that exhibit associations with other pathologies were selected. These pathologies include diabetes, dyslipidemia, cardiovascular and liver diseases, among others. Conclusions: Hypothyroidism is a prevalent pathology that is frequently associated with many other comorbidities that must be taken into account when dealing with these patients, and thus make the best diagnostic and therapeutic decisions.
Assuntos
Humanos , Masculino , Feminino , COVID-19 , Hipotireoidismo/complicações , Hipotireoidismo/etiologia , Hipotireoidismo/epidemiologia , Doenças da Glândula Tireoide/epidemiologia , Doenças Cardiovasculares , Diabetes Mellitus , Dislipidemias , Infertilidade , Nefropatias , ObesidadeRESUMO
INTRODUCTION: Levothyroxine (LT4) has been considered the standard of care for treatment of hypothyroidism. Current recommendations suggest a LT4 dose between 1.6-1.8 µg/kg/day. The aim of this study was to evaluate the LT4 dose for adult patients with primary hypothyroidism of different etiologies who reached euthyroidism. METHODS: A cross-sectional study was performed from the retrospective review of the charts of patients with primary hypothyroidism in treatment with LT4. Subjects were classified according to TSH level in overtreated (TSHâ<â0.4 µIU/ml), euthyroid (TSH 0.40-4.20), and undertreated (TSHâ>4.2) and according to the etiology of hypothyroidism. A stepwise logistic regression model was performed to evaluate the variables associated with TSH<0.4 µIU/ml. RESULTS: 955 patients were included. 75.13% of the patients had an adequate LT4 replacement. LT4 dose to achieve euthyroidism was higher in patients with a history of radioiodine therapy (1.92 µg/kg) and thyroid surgery (1.52 µg/kg), while the LT4 dose required to achieve euthyroidism in patients with Hashimoto's thyroiditis and atrophic thyroiditis was lower than that reported in previous studies (1.25 and 1.08 µg/kg, respectively). The variables that were associated with a higher probability of TSH<0.4 µIU/ml were male gender, Hashimoto's thyroiditis, radioiodine therapy, and thyroid surgery. MAJOR CONCLUSION: LT4 dose required to achieve euthyroidism in patients with hypothyroidism varies according to the etiology, being higher in patients with hypothyroidism due to radioiodine therapy and thyroid surgery. Patients with hypothyroidism due to Hashimoto's thyroiditis and atrophic thyroiditis require a lower dose than current recommendations.
Introducción: La levotiroxina (LT4) se considera el estándar de tratamiento del hipotiroidismo. Las recomendaciones actuales sugieren una dosis de LT4 entre 1,6-1,8 µg/kg/día. El objetivo de este estudio fue evaluar la dosis de LT4 en pacientes adultos con hipotiroidismo primario de diferentes etiologías que alcanzaron el eutiroidismo. Métodos: Estudio transversal a partir de la revisión retrospectiva de historias clínicas de pacientes con hipotiroidismo primario en tratamiento con LT4. Los sujetos se clasificaron según el nivel de TSH en sobretratados (TSH<0,4 µUI/ml), eutiroideos (TSH 0,40-4,20) y subtratados (TSH>4,2) y según la etiología del hipotiroidismo. Se realizó un modelo de regresión logística escalonada para evaluar las variables asociadas con TSH <0,4 µUI/ml. Resultados: Se incluyeron 955 pacientes. El 75,13% tuvo un reemplazo adecuado de LT4. La dosis de LT4 para lograr el eutiroidismo fue mayor en pacientes con antecedentes de terapia con yodo radiactivo (1,92 µg/kg) y cirugía de tiroides (1,52 µg/kg), mientras que la dosis de LT4 para lograr el eutiroidismo en pacientes con tiroiditis de Hashimoto y tiroiditis atrófica fue menor que el reportado en estudios previos (1,25 y 1,08 µg/kg, respectivamente). Las variables que se asociaron con una mayor probabilidad de TSH<0,4 µUI/ml fueron el sexo masculino, tiroiditis de Hashimoto, terapia con yodo radiactivo y cirugía de tiroides. Conclusión principal: La dosis de LT4 necesaria para alcanzar el eutiroidismo en pacientes con hipotiroidismo varía según la etiología, siendo mayor en pacientes con hipotiroidismo por tratamiento con yodo radiactivo y cirugía tiroidea. Los pacientes con hipotiroidismo debido a tiroiditis de Hashimoto y tiroiditis atrófica requieren una dosis más baja que las recomendaciones actuales.
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Doenças Autoimunes , Hipotireoidismo , Tireoidite , Adulto , Humanos , Masculino , Feminino , Tiroxina/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Estudos Transversais , Tireotropina/uso terapêutico , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/etiologia , Doenças Autoimunes/tratamento farmacológico , Tireoidite/tratamento farmacológicoRESUMO
The aim of this study was to evaluate the impact of photobiomodulation therapy (PBMT) on histomorphological aspects of submandibular gland (SMG) submitted to salivary gland duct obstruction in hypothyroid rats. Fifty-six male Wistar rats (250 to 300 g) were divided into 4 groups (n = 14): euthyroid (EU), EU + PBMT, hypothyroid (HYPO), and HYPO + PBMT. Duct obstruction of the left submandibular gland (LSMG) was performed in all animals by a ligature procedure. For the induction of hypothyroidism, total thyroidectomy was performed. PBMT groups received irradiation with AlGaInP diode laser (808 nm, 0.04 W, 0.04cm2 spot size, 60 s, 2.4 J per point, 60 J/cm2, 1 W/cm2). Irradiation was performed immediately, 24 h, and 48 h after the obstruction of the salivary gland duct, in one point, extra oral and perpendicular to the gland. Animals were sacrificed after 24 h and 72 h after duct ligature. Our results indicated that salivary duct obstruction and hypothyroidism caused negative modifications on the salivary glands' histomorphology, especially acinar atrophy, after 24 h and 72 h. HYPO + PBMT showed a significant reduction of the inflammatory infiltrate, congested blood vessels, and acinar atrophy in the SMG submandibular salivary gland in 72 h compared to 24 h (p < 0.05). In conclusion, obstruction of the salivary gland excretory duct and hypothyroidism causes severe sialoadenitis with expressive atrophy of the glandular parenchyma. However, PBMT was able to modulate the inflammatory process and delaying acinar atrophy. This study provided insights to better understand the role of the PBMT on the altered salivary gland by duct ligation and associate hypothyroidism.
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Hipotireoidismo , Terapia com Luz de Baixa Intensidade , Animais , Hipotireoidismo/etiologia , Hipotireoidismo/radioterapia , Ligadura , Masculino , Ratos , Ratos Wistar , Ductos Salivares , Glândula SubmandibularRESUMO
INTRODUCTION: Hypothyroidism has been associated with dyslipidemia. Its treatment with levothyroxine has shown a positive effect on the lipid profile in adults, however, there is a lack of data on the pediatric popu lation. OBJECTIVE: to evaluate the effect of the thyroid profile normalization on the lipid profile in children with primary hypothyroidism. PATIENTS AND METHOD: Retrospective study in children aged from 6 to 16 years, with diagnosis of primary hypothyroidism due to Hashimoto's thyroiditis, in treatment with levothyroxine, and who had an evaluation of serum lipids before and during their treatment. The lipid profile was evaluated in 2 stages: the first one referred to as "before levothyroxine treatment" (at the diagnosis of primary hypothyroidism) and the second one referred to as " thyroid profile normalization" (when normalization of Thyroid-stimulating hormone [TSH] and free T4 [FT4] was achieved during levothyroxine treatment). Sociodemographic and anthropometric data were recorded. The lipid profile evaluation consisted of the serum determination of total cholesterol (TC), high-density cholesterol (HDL-C), and TG. The phenotype of dyslipidemias was determined according to the Fredrickson's classification. RESULTS: 72 patients were included (61% women; age 11.5 ± 2.9 years), out of which 58.3% (n = 42) presented pre-treatment dyslipidemia. In hypothyroid state, it was evident the correlation of TSH with TC (r = 0.36; p = 0.002), LDL-C (r = 0.46; p = 0.01), and HDL-C (r = -0.33; p = 0.004). The thyroid profile normalization showed the reduction of TC [184 mg/dL (IQR 92-322) vs 147 mg/dL (IQR 92-283); p = 0.05], LDL-C [99 mg/dL (IQR 44-232) vs 82 mg/dL (IQR 41-168); p = 0.02], TG [113 mg/dL (IQR 50-483) vs 88 mg/dL (IQR 16-343); p = 0.03], and the frequency of dyslipidemia [58.3% vs 22.2%; p = 0.001), as well as the TC correction with TG (r = 0.35; p = 0.02) and LDL-C (r = 0.88; p = 0.01). Persistent dyslipidemia was associated with obesity (r = 0.27; p = 0.02), overweight (r = 0.58; p = 0.001), and pre-treatment dyslipidemia (r = 0.53; p = 0.001). CONCLUSIONS: There is an association between TSH, TC, LDL-C, and HDL-C in hypothyroidism. When the thyroid profile was normalized, there was a reduction of TC, TG, LDL- C, and dyslipidemia frequency. Persistent dyslipidemia was associated with obesity, overweight, and pre-treatment dyslipidemia.
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Hipotireoidismo/sangue , Lipídeos/sangue , Tireotropina/sangue , Tiroxina/sangue , Adolescente , Criança , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dislipidemias/sangue , Dislipidemias/classificação , Dislipidemias/complicações , Feminino , Doença de Hashimoto/complicações , Humanos , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/etiologia , Masculino , Obesidade Infantil/etiologia , Valores de Referência , Estudos Retrospectivos , Tiroxina/uso terapêutico , Triglicerídeos/sangueRESUMO
To verify the viability and functionality of cryopreserved thyroid autotransplantation in rats who underwent total thyroidectomy in the treatment of postoperative hypothyroidism. Thirty-two Wistar rats were randomly assigned into groups (G) with eight animals each: control (CG); simulation (SG); hypothyroidism (HTG) and transplanted (TG). At the beginning and in the 13th week of the experiment, serum levels of total T3, free T4, TSH and calcium were determined. In both the first and 14th weeks, scintigraphic examinations, 99m-Tc pertechnetate radioisotope biodistribution and histopathology were performed. In the 14th week, the expression of proliferating cell nuclear antigen (PCNA) and cellular apoptosis (caspase-3) were also evaluated. In the 13th week, the transplanted animals had normal serum levels of total T3 and free T4. TSH levels showed a tendency towards normality. In the 14th week, scintigraphic exams displayed graft isotopic uptake in all animals in the TG group. Histological examinations 13 weeks after transplantation showed the viability and functionality of thyroid follicles. PCNA revealed significant immunoreactivity of the graft (p < 0.001) when the TG was compared to the CG. There was no difference between CG and TG considering the expression of activated caspase-3. The experimental study confirmed the viability and functionality of thyroid autotransplantation implanted in skeletal muscle with evidence of cell proliferation without cellular apoptosis. This surgical strategy was effective in the treatment of postoperative hypothyroidism.
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Hipotireoidismo/cirurgia , Complicações Pós-Operatórias/cirurgia , Glândula Tireoide/transplante , Tireoidectomia/efeitos adversos , Animais , Hipotireoidismo/sangue , Hipotireoidismo/etiologia , Masculino , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Ratos , Ratos Wistar , Tiroxina/sangue , Transplante Autólogo , Tri-Iodotironina/sangueRESUMO
As pregnant women are susceptible to changes in iodine, which can cause miscarriage, goiter, thyroid nodules, hypothyroidism, in addition to fetal neurological impairment or development. The aim of this study was to verify the implications of the iodine alteration in each gestational trimester and its consequences of physiological justification. The review was based on PRISMA. Searching for articles that took place in March 2020 without delimiting data. As bases consulted were the Clinical Trials, Cochrane Library, Lilacs and Medline (PubMed). The descriptors were combined as follows: "pregnancy" AND "iodine deficiency". Articles that addressed iodine deficiency and its implications were included. The selection followed the steps of reading the titles, abstracts and full articles. To assess the methodological quality of the studies, the STROBE Instruction instrument was used. The research resulted in 1,266 studies and 11 were included. In assessing methodological quality, the lowest score was and the maximum 20. According to studies, the fourth most affected by iodine loss are the second and third, it is possible to increase the volume and pneumatic nodules, subclinical hypothyroidism, pre-eclampsia, among others. The damages caused by iodine deficiency in the first or second trimester are still reversible, therefore, they need to be diagnosed early, to guarantee an iodic homeostasis and prevent damage to the health of the mother-child binomial.
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Bócio , Hipotireoidismo , Iodo , Complicações na Gravidez , Criança , Feminino , Humanos , Hipotireoidismo/etiologia , Gravidez , Complicações na Gravidez/etiologia , Trimestres da GravidezRESUMO
El hipotiroidismo es la disfunción tiroidea más frecuente, resultante de una disminución de la actividad biológica de las hormonas tiroideas en los tejidos. El objetivo es realizar una revisión y actualización del hipotiroidismo adquirido en la infancia y adolescencia con énfasis en el hipotiroidismo primario. La causa más común es la tiroiditis de Hashimoto o tiroiditis linfocitaria crónica. La característica distintiva es el impacto profundo en el crecimiento esquelético, maduración y desarrollo puberal, con potencial repercusión en la talla adulta. Los signos y síntomas del hipotiroidismo adquirido son similares a los adultos y, en general, no se asocia con compromiso del desarrollo neuromadurativo.La presunción clínica se confirma con niveles elevados de tirotrofina y disminuidos de tiroxina libre. Las metas del tratamiento incluyen lograr adecuado crecimiento, maduración sexual, desarrollo neuromadurativo y cognitivo óptimo. En la mayoría de los pacientes, el tratamiento de reemplazo revierte los signos y síntomas.
Hypothyroidism is the most frequent thyroid dysfunction. It is the consequence of a decrease in the biological activity of thyroid hormones in target tissues. The aim of this paper is to review and update acquired hypothyroidism in childhood and adolescence with emphasis on primary hypothyroidism due to its greater frequency. Hashimoto's thyroiditis, also known as chronic lymphocytic thyroiditis, is the most common cause of primary acquired hypothyroidism. The distinctive feature is the profound impact on skeletal growth, maturation, and pubertal development, with potential implications on adult height. Signs and symptoms of acquired hypothyroidism are similar to those reported in adults and are generally not associated with neurodevelopmental impairment. Biochemi confirmation of primary hypothyroidism requires the finding of elevated thyrophine and decreased free thyroxine levels. Treatment goals are to achieve normal growth and maturation as well as cognitive development. In most of the patients, replacement treatment reverses symptoms and signs of hypothyroidism and may decrease goiter size.
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Humanos , Masculino , Feminino , Criança , Adolescente , Hipotireoidismo/diagnóstico , Hipotireoidismo/terapia , Doença de Hashimoto , Bócio , Hipotireoidismo/etiologiaRESUMO
PURPOSE: The potential benefits of treating subclinical hypothyroidism (SCH) are unclear and still controversial. Thus, we surgically induced SCH in rats and evaluated the effects of thyroxine (T4) replacement on the gene expression levels of deiodinases and thyroid hormone (TH) transporters in different tissues. METHODS: SCH was induced by hemithyroid electrocauterization. The control animals underwent the same surgical procedure but were not subjected to electrocauterization (sham). After 14 days, half of the SCH animals were treated with T4 (SCH + T4). At the end of the experimental protocol, all of the rats were euthanized, serum hormone concentrations were measured, and RNA analyses were performed on different tissues and organs. RESULTS: Consistent with previous studies, we observed increased TSH levels, normal TH levels, and reduced hypothalamic TRH expression in the SCH group. Additionally, Dio2 mRNA expression was downregulated in the hippocampus and pituitary, and Dio1 was upregulated in the kidney and pituitary of the SCH animals. The changes in Dio3 expression were tissue-specific. Concerning TH transporters, Mct10 expression was upregulated in the pituitary, kidney, hypothalamus, and hippocampus, and Mct8 expression was downregulated in the kidney of the SCH group. Crym expression was upregulated in the kidney and pituitary. Notably, T4 replacement significantly attenuated serum TSH levels and reverted Dio1, Dio2, Mct10, and Crym expression in the pituitary, hippocampus, and kidney to levels that were similar to the sham group. Tissue-specific responses were also observed in the liver and hypothalamus. CONCLUSION: Our results indicate that treatment of SCH should be considered before the appearance of clinical symptoms of hypothyroidism.