Thyroid stimulating hormone levels in cord blood are not influenced by non-thyroidal mothers' diseases

CONTEXT: Screening programs not only offer the opportunity to trace and treat almost all cases of congenital hypothyroidism but also mean large savings to the health system. However, carefully planned strategies are necessary to extend their benefits and reduce costs. OBJECTIVE: To determine the possible influence of maternal diseases that affect maternal-fetal placenta dynamics on primary thyroid stimulating hormone (TSH) screening for congenital hypothyroidism. DESIGN: Prospective non-randomized clinical trial with at least 3 months of follow-up. SETTING: A public university referral center [CAISM/Hospital das Clínicas, Faculty of Medicine, University of Campinas, Campinas, SP]. PARTICIPANTS: 415 neonates divided into 5 groups: eighty-three infants born from cardiac mothers; 98 from mothers that had toxemia; 54 of the mothers had diabetes mellitus; 40 were HIV positive and 140 had no diseases. INTERVENTION: All newborns had cord blood samples collected on filter paper at birth. MAIN MEASUREMENTS: TSH was measured from dried blood spots using a homemade immunofluorescence assay (sensitivity in dried blood spots = 0.1 mU/L). RESULTS: There was no significant difference in the mean TSH levels among the 5 groups. Moreover, TSH levels were around 5 mU/L in 48% of the newborns, indicating that our region is severely deficient in iodine. CONCLUSIONS: Our results indicate that primary TSH screening programs using cord blood are not affected by maternal diseases. We suggest that, besides its technical advantages over heel punctures with T4 primary approaches, neonatal screening using primary cord blood TSH may also be used as a monitoring tool for evaluation and control of iodine deficiency disorders (IDD).CONTEXTO: Os programas de detecção precoce trazem economias ao sistema de saúde e oferecem a oportunidade de rastrear e tratar precocemente casos de hipotiroidismo congênito. OBJETIVO: Determinar influências de doenças que afetam a dinâmica materno-fetal-placentária sobre programas de detecção precoce de hipotiroidismo congênito que se baseiam na dosagem do hormônio tirotrófico (TSH). TIPO DE ESTUDO: Ensaio clínico prospectivo não-randomizado com, ao menos, três meses de seguimento. LOCAL: Centro Universitário Público de Referência - Centro de Atendimento Integrado a Saúde da Mulher (CAISM). PARTICIPANTES: 415 recém-nascidos de 5 grupos de parturientes: 83 crianças eram filhas de mães cardiopatas; 98 de mães com toxemia gravídica; 54 de mães diabéticas; 40 de mães portadoras de imunodeficiência adquirida (HIV); e 140 de mães hígidas. PROCEDIMENTOS: Todos os recém-nascidos tiveram amostras de sangue de cordão umbilical coletadas em papel de filtro ao nascimento. VARIÁVEIS ESTUDADAS: Dosagem de TSH em sangue coletado em papel de filtro usando um ensaio imunofluorométrico próprio (sensibilidade em manchas de sangue seco = 0.1 mU/L). RESULTADOS: Não encontramos diferença na média de TSH dos 5 grupos. Além disso, os níveis de TSH estavam acima de 5 mU/L em 48% dos bebês, sugerindo que nossa região é severamente deficiente em iodo. CONCLUSÕES: Nossos resultados demonstram que programas de detecção precoce de hipotiroidismo congênito, que utilizam primariamente TSH, não são afetados por doenças maternas não-tiroidianas. Sugerimos que, além das vantagens técnicas sobre a punção de calcanhar com dosagem primária de T4, os programas de detecção precoce que utilizam primariamente TSH de cordão umbilical também podem ser usados como instrumento de avaliação e controle da carências de iodo.State University of Campinas Faculty of Medical Sciences Department of MedicineUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Department of MedicineUNIFESP, EPM, Department of MedicineSciEL

Factors affecting vitamin D status in different populations in the city of São Paulo, Brazil: the São Paulo vitamin D Evaluation Study (SPADES)

Background: Hypovitaminosis D is a common condition among elderly individuals in temperate-climate countries, with a clear seasonal variation on 25 hydroxyvitamin D [(25(OH)D] levels, increasing after summer and decreasing after winter, but there are few data from sunny countries such as Brazil. We aimed to evaluate 25-hydroxyvitamin D concentrations and its determining factors, in individuals in the city of São Paulo belonging to different age groups and presenting different sun exposure habits.Methods: 591 people were included as follows: 177 were living in institutions (NURSING HOMES, NH, 76.2 +/- 9.0 years), 243 were individuals from the community (COMMUNITY DWELLINGS, CD, 79.6 +/- 5.3 years), 99 were enrolled in physical activity program designed for the elderly (PHYSICAL ACTIVITY, PA, 67.6 +/- 5.4 years) and 72 were young (YOUNG, 23.9 +/- 2.8 years). Ionized calcium, PTH, 25(OH)D, creatinine and albumin were evaluated. ANOVA, Mann-Whitney and Kruskal Wallis tests, Pearson Linear Correlation and Multiple Regression were used in the statistical analysis.Results: 25(OH)D mean values during winter for the different groups were 36.1 +/- 21.2 nmol/L (NH), 44.1 +/- 24.0 nmol/L (CD), 78.9 +/- 30.9 nmol/L (PA) and 69.6 +/- 26.2 nmol/L (YOUNG) (p < 0.001) while during summer they were 42.1 +/- 25.9 nmol/L, 59.1 +/- 29.6 nmol/L, 91.6 +/- 31.7 nmol/L and 103.6 +/- 29.3 nmol/L, respectively (p < 0.001). the equation which predicts PTH values based on 25(OH)D concentration is PTH = 10 + 104.24.e(-(vitD-12.5)/62.36) and the 25(OH)D value above which correlation with PTH is lost is 75.0 nmol/L. in a multiple regression analysis having 25(OH)D concentration as the depending variable, the determining factors were PTH, ionized calcium and month of the year (p < 0.05).Conclusions: Much lower 25(OH)D values were found for the older individuals when compared to younger individuals. This finding is possibly due to age and habit-related differences in sunlight exposure. the existence of seasonal effects on 25(OH)D concentration throughout the year was evident for all the groups studied, except for the nursing home group. According to our data, PTH values tend to plateau above 75 nmol/L.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo UNIFESP, Escola Paulista Med, Dept Med, Div Endocrinol, Sao Carlos, SP, BrazilUNIFESP, Dept Geriatr Med, Sao Carlos, SP, BrazilUNIFESP, Dept Prevent Med, Sao Carlos, SP, BrazilUniversidade Federal de São Paulo UNIFESP, Escola Paulista Med, Dept Med, Div Endocrinol, Sao Carlos, SP, BrazilUNIFESP, Dept Geriatr Med, Sao Carlos, SP, BrazilUNIFESP, Dept Prevent Med, Sao Carlos, SP, BrazilFAPESP: 03/13194-6Web of Scienc

Usefulness of intraoperative PTH measurement in primary and secondary hyperparathyroidism: experience with 109 patients

INTRODUCTION: Intraoperative parathyroid hormone measurement (IO-PTH) was first described in 1988 and it's potentially useful in predicting cure after parathyroidectomy. The aim of this study was to evaluate IO-PTH decay profile and the utility of this procedure in predicting cure in primary (PHH) and secondary (SHH) hyperparathyroidism due to renal disease. PATIENTS AND METHODS: 109 patients were evaluated from 06/2000 to 12/2004. 33 had PHH and 76 SHH (52 in dialysis, 24 with renal graft). IO-PTH was measured at times 0 (before resection), 10, 20 minutes after parathyroidectomy using immunometric assay (Elecsys-PTH/Immunoassay-Roche). Time necessary to perform assay: 10 minutes. RESULTS: HPP patients: IO-PTH average decrease 79.2% from basal levels after 10 minutes. HPS: IO-PTH average decrease 85.8% and 87.6% after 10 minutes in dialysis and renal graft patients respectively. All patients were cured, except 2 (1 PHH, 1 SHH), because of a double adenoma and ectopic (mediastinal) parathyroid respectively. Failure in IO-PTH decrease was observed in both. CONCLUSION: IO-PTH measurement is useful in improving surgical success rates in PHH and SHH.INTRODUÇÃO: A medida de PTH intra-operatório (PTH-IO) foi inicialmente descrita em 1988, sendo potencialmente útil na definição de sucesso após a paratiroidectomia. OBJETIVOS: Avaliar prospectivamente perfil de decaimento do PTH-IO e sua capacidade de prever sucesso cirúrgico no hiperparatiroidismo primário (HPP) e secundário à insuficiência renal (HPS). PACIENTES E MÉTODOS: 109 pacientes operados entre 06/2000 e 12/2004, sendo 33 HPP, 76 HPS (52 em diálise, 24 transplantados renais). PTH-IO: método imunométrico rápido (Elecsys-PTH/Immunoassay-Roche); tempo para resultado: 10 minutos. Coletas de sangue periférico nos tempos basal, 10 e 20 minutos pós-paratiroidectomia. RESULTADOS: HPP: queda média de PTH de 79,2% aos 10 minutos. HPS: queda média de PTH de 85,8% e 87,6% aos 10 minutos nos pacientes diálise e transplantados respectivamente. A cirurgia foi bem sucedida em todos, exceto em 2 pacientes (1 HPP, 1 HPS). Em ambos não houve queda PTH-IO, sendo constatado adenoma duplo no HPP e paratiróide ectópica no HPS. CONCLUSÃO: Medida PTH-IO fornece resultados confiáveis em tempo rápido, sendo capaz de discriminar persistência da doença se mantidos níveis elevados.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL

Molecular cloning of ion channels in Felis catus that are related to periodic paralyses in man: a contribution to the understanding of the genetic susceptibility to feline neck ventroflexion and paralysis

Neck ventroflexion in cats has different causes; however, the most common is the hypokalemia associated with flaccid paralysis secondary to chronic renal failure. in humans, the most common causes of acute flaccid paralysis are hypokalemia precipitated by thyrotoxicosis and familial forms linked to mutations in sodium, potassium, and calcium channel genes. Here, we describe the sequencing and analysis of skeletal muscle ion channels in Felis catus that could be related to periodic paralyses in humans, contributing to the understanding of the genetic susceptibility to feline neck ventroflexion and paralysis. We studied genomic DNA from eleven cats, including five animals that were hyperthyroid with hypokalemia, although only one presented with muscle weakness, and six healthy control domestic cats. We identified the ion channel ortholog genes KCNJ2, KCNJ12, KCNJ14, CACNA1S and SCN4A in the Felis catus genome, together with several polymorphic variants. Upon comparative alignment with other genomes, we found that Felis catus provides evidence for a high genomic conservation of ion channel sequences. Although we hypothesized that neck ventroflexion in cats could be associated with a thyrotoxic or familial periodic paralysis channel mutation, we did not identify any previously detected human channel mutation in the hyperthyroid cat presenting hypokalemia. However, based on the small number of affected cats in this study, we cannot yet rule out this molecular mechanism. Notwithstanding, hyperthyroidism should still be considered as a differential diagnosis in hypokalemic feline paralysis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Escola Paulista Med, Dept Med, Div Endocrinol,Lab Mol & Translat Endocrinol, BR-04039032 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Med, Div Endocrinol,Lab Mol & Translat Endocrinol, BR-04039032 São Paulo, BrazilFAPESP: 2011/20747-8FAPESP: 2012/02529Web of Scienc