BackgroundThe mechanism behind parathyroid hormone (PTH) activation of bone remodeling is intimately dependent on the time of exposure of bone cells to hormone levels. Sustained high PTH levels trigger catabolism, while transitory elevations induce anabolism. The effects of hypoparathyroidism (PhPT) on bone are unknown. The objective was to study the impact of PhPT on bone mineral density (BMD), on the frequency of subclinical vertebral fracture and on mandible morphometry.MethodsThe study comprised thirty-three postmenopausal women, 17 controls (CG) and 16 with PhPT (PhPTG) matched for age, weight and height. Bone mineral density (BMD) of lumbar spine, total hip and 1/3 radius, radiographic evaluation of vertebral morphometry, panoramic radiography of the mandible, and biochemical evaluation of mineral metabolism and bone remodeling were evaluated in both groups.ResultsThere were no significant differences in lumbar spine or total hip BMD between groups. There was marked heterogeneity of lumbar spine BMD in PhPTG (high = 4, normal = 9, osteopenia = 1, and osteoporosis = 2 patients). BMD was decreased in the 1/3 radius in PhPTG P < 0.005). The PhPTG group exhibited an increased frequency of morphometric vertebral fractures and decreased mandible cortical thickness.ConclusionThe study suggests that vertebral fragility occurs in PhPT despite normal or even high BMD. The current results encourage further studies to evaluate the use of panoramic radiography in the identification of osteometabolic disorders, such as PhPT and the development of a more physiological treatment for PhPT.

SIntroduction: Hyperthyroidism is characterized by increased synthesis and release of thyroid hormones by the thyroid gland. Thyrotoxicosis refers to the clinical syndrome resulting from excessive circulating thyroid hormones, secondary to hyperthyroidism or due to other causes. This article describes evidence-based guidelines for the clinical management of thyrotoxicosis. Objective: This consensus, developed by Brazilian experts and sponsored by the Department of Thyroid Brazilian Society of Endocrinology and Metabolism, aims to address the management, diagnosis and treatment of patients with thyrotoxicosis, according to the most recent evidence from the literature and appropriate for the clinical reality of Brazil. Materials and methods: After structuring clinical questions, search for evidence was made available in the literature, initially in the database Medline, PubMed and Embase databases and subsequently in SciELO -Lilacs. The strength of evidence was evaluated by Oxford classification system was established from the study design used, considering the best available evidence for each question. Results: We have defined 13 questions about the initial clinical approach for the diagnosis and treatment that resulted in 53 recommendations, including the etiology, treatment with antithyroid drugs, radioactive iodine and surgery. We also addressed hyperthyroidism in children, teenagers or pregnant patients, and management of hyperthyroidism in patients with Graves' ophthalmopathy and various other causes of thyrotoxicosis. Conclusions: The clinical diagnosis of hyperthyroidism usually offers no difficulty and should be made with measurements of serum TSH and thyroid hormones. The treatment can be performed with antithyroid drugs, surgery or administration of radioactive iodine according to the etiology of thyrotoxicosis, local availability of methods and preferences of the attending physician and patient. Arq Bras Endocrinol

Differently from most hormones, which commonly are specialized molecules able to influence other cells, tissues and systems, thyroid hormones (TH) are pleiotropic peptides, whose primordial function is difficult to identify. The complex action of TH on human economy can be easily witnessed by examining the diverse consequences of TH excess and deficiency during development and after maturity. In particular, different manifestations in bone modeling and remodeling reflect the circumstantial consequences of thyroid disturbances, which are age dependent. While hyperthyroidism during childhood enhances bone mineralization and accelerates epiphyseal maturation, in adults it induces bone loss by predominant activation of osteoclast activity. Furthermore, the syndrome of TH resistance is a multifaceted condition in which different sites exhibit signs of hormone excess or deficiency depending on the configuration of the TH receptor isoform. The investigation of the impact of TH resistance on the skeleton still remains to be elucidated. We present here a thorough review of the action of TH on bone and of the impact of thyroid disorders, including hyper-and hypothyroidism and the syndrome of TH resistance, on the skeleton. Arq Bras Endocrinol Metab. 2014;58(5):452-63 Keywords Thyroid hormones; osteoporosis; thyrotoxicosis; hypothyroidism; thyroid hormone resistance ReSumoDiferentemente da maioria dos hormônios, que usualmente são moléculas especializadas capazes de influenciar outras células, tecidos e sistemas, os hormônios da tireoide (HT) são peptídeos pleiotrópicos, cuja função primordial é difícil de identificar. A ação complexa dos HT na fisiologia humana pode ser facilmente reconhecida ao observar as diversas consequências do excesso e da deficiência de HT durante e após o pleno desenvolvimento. Em particular as diferentes manifestações na modelação e remodelação óssea refletem que as consequências esqueléticas das disfunções tireoidianas dependem das circunstâncias e variam com a idade. Enquanto o hipertireoidismo durante a infância aumenta a mineralização óssea e acelera a maturação epifisária, em adultos induz a perda óssea pela ativação predominante da ação osteoclástica. Além disso, a síndrome de resistência ao HT é uma condição multifacetada na qual diferentes tecidos apresentam sinais de excesso ou deficiência hormonal, dependendo da predominância da expressão das diversas isoformas do receptor de HT. O impacto da resistência ao HT sobre o esqueleto ainda é motivo de investigação. Apresentamos aqui uma revisão abrangente sobre as ações ósseas dos HT e o impacto no esqueleto dos distúrbios da tireoide, incluindo hipo e hipertireoidismo e síndrome de resistência ao HT. Arq Bras Endocrinol Metab.

Objective: The intake of adequate amounts of iodine during pregnancy is essential for the neurological development of the fetus. The aim of this study was to assess iodine nutrition status in pregnant women from the state of São Paulo, Brazil. Material and methods: We analyzed urinary iodine concentration (UIC) in 191 pregnant and 58 non-pregnant women matched by age. We used the World Health Organization criteria to define sufficient iodine supply (median UIC: 150-249 µg/L among pregnant women, and 100-199 µg/L for non-pregnant women). Results: Median UIC of the pregnant women studied was lower than the recommended value (median = 137.7 µg/L, 95% CI = 132.9 -155.9), while non-pregnant women had UIC levels within the appropriate range (median = 190 μg/L; 95% IC = 159.3-200.1). UIC was below 150 µg/L in 57% of the pregnant women. Conclusions: Although a larger sample is needed to consolidate these findings, these results raise concerns about the adequacy of the iodine supply of pregnant women in Brazil, especially considering the new determinations of the Brazilian government, which have recently reduced the concentrations of iodine in RESUMOObjetivo: O consumo de quantidade adequada de iodo durante a gestação é de fundamental importância para o desenvolvimento neurológico do feto. O objetivo deste estudo foi avaliar o estado nutricional iódico em gestantes do estado de São Paulo, Brasil. Material e métodos: Analisamos a concentração urinária de iodo (UIC) em 191 gestantes e em 58 mulheres não gestantes de mesma faixa etária. Foram utilizados os critérios da OMS para definir suficiência iódica (mediana de UIC: 150-249 µg/L entre as gestantes e 100-199 µg/L para as não gestantes). Resultados: A mediana de UIC das gestantes estudadas esteve abaixo da recomendada (mediana = 137,7 μg/L; 95% IC = 132,9 -155,9) enquanto a das mulheres não grávidas se mostrou na faixa adequada (mediana = 190 μg/L; 95% IC = 159,3 -200,1). Entre as gestantes, 57% apresentaram UIC < 150 μg/L. Conclusões: Apesar de uma maior amostragem ser necessária para a confirmação desses achados, os resultados levantam preocupação quanto à suficiência iódica nas mulheres grávidas no Brasil, principalmente diante das novas determinações governamentais brasileiras quanto à redução das concentrações de iodo no sal de cozinha para 15-45 mg/kg. Arq Bras Endocrinol Metab. 2014;58(3):282-7