Insulin signaling in the whole spectrum of GH deficiency

ABSTRACT GH is one of the insulin counterregulatory hormones which acts in the opposite way to insulin, increasing the glucose production by the liver and kidneys and decreasing glucose uptake from peripheral tissues, thus being a hyperglycemic hormone. When in excess, as in acromegaly, it induces glucose intolerance and diabetes. As expected, patients with GH deficiency (GHD) have hypoglycemia, especially in early childhood, but as GH is also a lipolytic hormone, these patients are becoming obese with higher percentages of body fat. Although obesity in general is directly related to insulin resistance, in patients with GH secretion disorders this relationship may be altered. In acromegaly there is a decrease in fat mass with worsening insulin sensitivity and mice with isolated GHD are characterized by greater insulin sensitivity despite excess fat mass. In humans with GHD, body composition shows increased body fat and decreased free fat mass, but the results regarding insulin sensitivity are still controversial in these patients. These discrepant results regarding insulin sensitivity in patients with GHD suggest the existence of other variables influencing these results. In the present review, we will try to follow the path of the different researches conducted on this subject, both in animal and human models, with the goal of understanding the current knowledge of insulin sensitivity across the spectrum of GHD. Arch Endocrinol Metab. 2019;63(6):582-91

Controversial issues in the management of hyperprolactinemia and prolactinomas - An overview by the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism

ABSTRACT Prolactinomas are the most common pituitary adenomas (approximately 40% of cases), and they represent an important cause of hypogonadism and infertility in both sexes. The magnitude of prolactin (PRL) elevation can be useful in determining the etiology of hyperprolactinemia. Indeed, PRL levels > 250 ng/mL are highly suggestive of the presence of a prolactinoma. In contrast, most patients with stalk dysfunction, drug-induced hyperprolactinemia or systemic diseases present with PRL levels < 100 ng/mL. However, exceptions to these rules are not rare. On the other hand, among patients with macroprolactinomas (MACs), artificially low PRL levels may result from the so-called "hook effect". Patients harboring cystic MACs may also present with a mild PRL elevation. The screening for macroprolactin is mostly indicated for asymptomatic patients and those with apparent idiopathic hyperprolactinemia. Dopamine agonists (DAs) are the treatment of choice for prolactinomas, particularly cabergoline, which is more effective and better tolerated than bromocriptine. After 2 years of successful treatment, DA withdrawal should be considered in all cases of microprolactinomas and in selected cases of MACs. In this publication, the goal of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism (SBEM) is to provide a review of the diagnosis and treatment of hyperprolactinemia and prolactinomas, emphasizing controversial issues regarding these topics. This review is based on data published in the literature and the authors' experience.

Thyroid-stimulating Hormone and Insulin Resistance: Their Association with Polycystic Ovary Syndrome without Overt Hypothyroidism / Hormônio tireoestimulante e resistência insulínica: sua associação com a síndrome do ovário policístico sem hipotireoidismo clínico

Abstract Objective This study analyzed the effectiveness of the thyroid-stimulating hormone (TSH) as a predictor of insulin resistance (IR) and its association with the clinical and metabolic parameters of women with polycystic ovary syndrome (PCOS) without overt hypothyroidism. Study Design A cross-sectional study was performed. Women with PCOS and without overt hypothyroidism (n = 168) were included. Methods Receiver operating characteristic (ROC) curve was used to determine the cut-off point for TSH that would maximize sensitivity and specificity for a diagnosis of IR using homeostatic model assessment of insulin resistance (HOMA-IR)≥ 2.71. Clinical and metabolic parameters were compared as a function of the TSH cut-off limit and the presence of IR. Results Thyroid-stimulating hormone ≥ 2.77 mIU/L was associated with a diagnosis of IR, with sensitivity of 47.9% and specificity of 65.3%. There were no differences in clinical, hormonal or metabolic parameters between TSH < 2.77 and TSH of 2.77 - 10 mIU/L. Conclusion In women with PCOS without overt hypothyroidism, TSH ≥2.77 mIU/L is associated with IR; however, with poor sensibility, showing TSH to be a poor predictor of IR in this population. No clinical or metabolic alterations were found that would justify a change in clinical management. Thus, the IR should be investigated in all women with PCOS irrespective of TSH level.

Resumo Objetivo Este estudo analisou a efetividade do hormônio tireoestimulante (TSH) como preditor da resistência insulínica (IR), bem como a associação do TSH com os parâmetros clínicos e metabólicos de mulheres com síndrome do ovário policístico (PCOS) sem hipotireoidismo clínico. Desenho do Estudo Estudo de corte transversal com inclusão de mulheres com PCOS e sem hipotireoidismo clínico (n =168). Métodos Utilizou-se análise através de curva ROC (Receiver operating characteristic) para determinar o valor de corte para o nível sérico de TSH que poderia maximizar a sensibilidade e especificidade para o diagnóstico de IR considerada com avaliação da homeostase de resistência insulínica (HOMA-IR) ≥ 2.71. Parâmetros clínicos e metabólicos foram comparados de acordo com o ponto de corte de TSH determinado e com a presença de IR. Resultados Níveis séricos de TSH ≥2.77 mIU/L estiveram associados com o diagnóstico de IR, com sensibilidade de 47.9% e especificidade de 65.3%. Não foram evidenciadas diferenças nos parâmetros clínicos, hormonais e metabólicos quando TSH < 2.77 ou TSH de 2.77 - 10 mIU/L. Conclusão Em mulheres com PCOS sem hipotireoidismo, TSH ≥2.77 mIU/L está associado a IR, porém com baixa sensibilidade, mostrando que a dosagem de TSH não é um bom preditor de IR nesta população. Também não se evidenciou alteração clínica ou metabólica que justificasse alteração na investigação desta população. Assim, a resistência insulínica deve ser investigada em todas as mulheres com PCOS, independente dos níveis séricos de TSH.

Pituitary macroadenoma presenting as a nasal tumor: case report / Macroadenoma hipofisário, apresentando-se como um tumor nasal: relato de caso

CONTEXT: Pituitary macroadenomas are rare intracranial tumors. In a few cases, they may present aggressive behavior and invade the sphenoid sinus and nasal cavity, causing unusual symptoms. In this paper, we report an atypical case of pituitary adenoma presenting as a nasal mass. CASE REPORT: The patient was a 44-year-old woman who had had amenorrhea and galactorrhea for ten months, with associated nasal obstruction, macroglossia and acromegaly. Both growth hormone and prolactin levels were increased. Magnetic resonance imaging showed a large mass originating from the lower surface of the pituitary gland, associated with sella turcica erosion and tumor extension through the sphenoid sinus and nasal cavity. Histopathological analysis demonstrated a chromophobe pituitary adenoma with densely packed rounded epithelial cells, with some atypias and rare mitotic figures. There was no evidence of metastases. CONCLUSION: Macroadenoma invading the nasal cavity is a rare condition and few similar cases have been reported in the literature. This study contributes towards showing that tumor extension to the sphenoid sinus and nasopharynx needs to be considered and investigated in order to make an early diagnosis when atypical symptoms like nasal obstruction are present. .

CONTEXTO: Macroadenomas hipofisários são tumores intracraniais raros. Em alguns casos, podem apresentar comportamento agressivo e invadir o seio esfenoidal e a cavidade nasal, causando sintomas não usuais. Neste relato de caso, descrevemos um caso atípico de adenoma hipofisário manifestando-se como uma massa nasal. RELATO DE CASO: A paciente de 44 anos, do sexo feminino, apresentava amenorreia e galactorreia por 10 meses associando-se a obstrução nasal, macroglossia e acromegalia. Os níveis do hormônio de crescimento e de prolactina apresentaram-se aumentados. Ressonância magnética mostrou uma grande massa originada da superfície inferior da glândula hipofisária associada com erosão da sela túrcica e extensão do tumor através do seio esfenoidal e cavidade nasal. Análise histopatológica demonstrou adenoma hipofisário cromófobo com células epiteliais arrendondadas densamente agrupadas com algumas atipias e escassas figuras de mitose. Não houve evidências de metástase. CONCLUSÃO: O macroadenoma invasivo para a cavidade nasal é uma condição rara e há poucos relatos similares descritos na literatura. Este trabalho contribui para mostrar que, na presença de sintomas atípicos como a obstrução nasal, a extensão para o seio esfenoidal e para a nasofaringe deve ser considerada e investigada para um diagnóstico precoce. .

Six new cases confirm the clinical molecular profile of complete combined 17α-hydroxylase/ 17,20-lyase deficiency in Brazil / Seis novos casos confirmam o perfil clínico molecular de deficiência combinada de 17 alfa-hidroxilase/17,20-liase no Brasil

In 2004, Costa-Santos and cols. reported 24 patients from 19 Brazilian families with 17α-hydroxylase deficiency and showed that p.W406R and p.R362C corresponded to 50 percent and 32 percent of CYP17A1 mutant alleles, respectively. The present report describes clinical and molecular data of six patients from three inbred Brazilian families with 17α-hydroxlyse deficiency. All patients had hypogonadism, amenorrhea and hypertension at diagnosis. Two sisters were found to be 46,XY with both gonads palpable in the inguinal region. All patients presented hypergonadotrophic hypogonadism, with high levels of ACTH (> 104 ng/mL), suppressed plasmatic renin activity, low levels of potassium (< 2.8 mEq/L) and elevated progesterone levels (> 4.4 ng/mL). Three of them, including two sisters, were homozygous for p.W406R mutation and the other three (two sisters and one cousin) were homozygous for p.R362C. The finding of p.W406R and p.R362C in the CYP17A1 gene here reported in additional families, confirms them as the most frequent mutations causing complete combined 17α-hydroxylase/17,20-lyase deficiency in Brazilian patients.

Em 2004, segundo Costa-Santos e cols., p.W406R e p.R362C correspondiam a 50 por cento e 32 por cento dos alelos mutantes do gene CYP17A1, respectivamente, em 24 pacientes de 19 famílias brasileiras com deficiência da 17α-hidroxilase. Apresentamos os dados clνnicos e moleculares de seis pacientes de três famílias consanguíneas brasileiras com deficiência da 17α-hidroxilase. Todas as pacientes apresentavam hipogonadismo, amenorreia e hipertensão ao diagnóstico. Duas irmãs tinham cariótipo 46,XY, ambas com gônadas palpáveis na região inguinal. Todas tinham hipogonadismo hipergonadotrófico, com nível aumentado de ACTH (> 104 ng/mL), atividade de renina plasmática suprimida, baixos níveis de potássio (< 2,8 mEq/L) e progesterona aumentada (> 4,4 ng/mL). Três delas, incluindo duas irmãs, apresentaram homozigose para a mutação p.W406R e as outras três (duas irmãs e uma prima) foram homozigotas para a mutação p.R362C. A recorrência das mutações p.W406R e p.R362C no gene CYP17A1 aqui relatada em famílias adicionais confirma que essas são as mais frequentes causadoras do fenótipo completo da deficiência combinada de 17α-hidroxilase/17,20-liase em pacientes brasileiros.

Long-term follow-up of an 8-year-old boy with insulinoma as the first manifestation of a familial form of multiple endocrine neoplasia type 1 / Seguimento de longo prazo em um menino de 8 anos de idade com insulinoma como primeira manifestação de neoplasia endócrina múltipla tipo 1

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant hereditary cancer syndrome characterized mostly by parathyroid, enteropancreatic, and anterior pituitary tumors. We present a case of an 8-year-old boy referred because of hypoglycemic attacks. His diagnosis was pancreatic insulinoma. Paternal grandmother died due to repeated gastroduodenal ulcerations and a paternal aunt presented similar manifestations. At a first evaluation, the father presented only gastric ulceration but subsequently developed hyperparathyroidism and lung carcinoid tumor. During almost 15 years of follow-up, three brothers and the index case presented hyperparathyroidism and hyperprolactinemia. Molecular study showed a G to A substitution in intron 4, at nine nucleotides upstream of the splicing acceptor site, causing a splicing mutation. All affected members of the family have the same mutation. Paternal grandmother and aunt were not studied and the mother does not carry any mutation. MEN1 is a rare condition that requires permanent medical assistance. Early clinical and genetic identification of affected individuals is essential for their own surveillance and also for genetic counseling.

A neoplasia endócrina múltipla tipo 1 (NEM1) é uma doença hereditária autossômica dominante, caracterizada principalmente por tumores de paratireoide, enteropancreáticos e adeno-hipofisários. Apresentamos o caso de um menino com 8 anos encaminhado por crises de hipoglicemia. Seu diagnóstico foi insulinoma pancreático. Sua avó paterna faleceu por úlceras gastroduodenais de repetição e a tia paterna tinha as mesmas manifestações. Na primeira avaliação, o pai apresentou apenas úlcera gástrica, porém com a evolução desenvolveu hiperparatireoidismo e tumor carcinoide pulmonar. Durante cerca de 15 anos de seguimento, os três irmãos e o caso índice desenvolveram hiperparatireoidismo e hiperprolactinemia. O estudo molecular mostrou a substituição G por A no intron 4, a nove nucleotídeos do sítio aceptor de splicing, criando um novo sítio de splicing. Todos os membros da família afetados e estudados tinham a mesma mutação. A NEM1 é uma condição rara que requer assistência médica permanente. As identificações clínicas e genéticas precoces são essenciais para o tratamento e aconselhamento genético.

Fatores determinantes do ganho na altura em meninas com puberdade precoce central idiopática tratadas com análogo de GnRH / Predictive factors for height gain in idiopathic central precocious puberty treated with GnRH analogues

OBJETIVO: avaliar fatores determinantes de maior ganho na estatura como resultado do tratamento com GnRHa. MÉTODOS: estudo retrospectivo de 33 meninas com puberdade precoce central idiopática tratadas com GnRHa. Foram avaliadas: idade no início dos sintomas e no início do tratamento, tempo decorrido entre o início de aparecimento dos caracteres puberais e o início do tratamento, idade óssea, avanço da idade óssea, duração do tratamento com GnRHa, altura real e escore Z, altura predita e escore Z e dosagens hormonais de FSH e LH após estímulo com GnRH, que foram correlacionadas com o ganho de altura no final do tratamento, calculada pela diferença entre altura predita no final e início do tratamento. Para análise estatística foi utilizada a correlação linear de Pearson, além da regressão linear múltipla. RESULTADOS: a média de idade no início do tratamento foi 7,8±1,3 anos, com idade óssea média de 10,1±1,6 anos. O avanço da idade óssea era de 2,3±1,1 anos e foi controlado com o tratamento. O ganho em altura predita foi de 2,5±1,3 cm e foi correlacionado positivamente com o tempo decorrido entre o início dos sintomas e o início do tratamento e com o avanço da idade óssea, além de se correlacionar negativamente com o escore Z da altura no início do tratamento e com a altura predita no início do tratamento, sendo este último o principal fator determinante do ganho obtido com o tratamento. CONCLUSÕES: meninas com maior comprometimento da altura predita para a idade adulta, visualizado pelo maior desvio em relação à população (escore Z) e pelo maior avanço na idade óssea foram as que obtiveram maior benefício com o tratamento com GnRHa, não devendo ser excluídas do grupo a ser tratado.

PURPOSE: to evaluate predictive factors of response to GnRHa treatment in girls with idiopathic central precocious puberty. METHODS: a retrospective cohort study was conducted involving 33 girls diagnosed with idiopathic central precocious puberty and treated with GnRHa. The following independent variables were assessed: age at the beginning of therapy and at the onset of symptoms, time elapsed since the appearance of pubertal characteristics and the beginning of treatment, bone age, bone age advance, duration of GnRHa treatment, actual height and Z-score, predicted height and Z-score and hormone measurements of FSH and LH after GnRH stimulation, which were correlated with gain in height as a dependent variable at treatment discontinuation, calculated by the difference between the predicted height at the end and beginning of treatment. For statistical analysis, Pearson's linear correlation was used, in addition to multiple linear regression analysis. RESULTS: the mean age at the beginning of treatment was 7.8±1.3 years, with a mean bone age of 10.1±1.6 years. Bone age advance was 2.3±1.1 years and was controlled during the treatment period. Gain in predicted height was 2.5±1.3cm. It was positively correlated with time elapsed since the beginning of symptoms and the beginning of treatment and with bone age advance, while negatively correlated with the Z-score of height at the beginning of treatment and predicted height at the beginning of treatment, and the latter was the main factor determining gain from treatment. CONCLUSIONS: girls who had the most significant compromise of predicted adult height, as detected by a larger deviation from the population (Z-score) and the most considerable advance in bone age, received benefit from GnRHa therapy, and they must not be excluded from the group to be treated.

Severe rhabdomyolysis due to adipsic hypernatremia after craniopharyngioma surgery

The association of diabetes insipidus and adipsia after craniopharyngioma surgery has high morbidity. Hypernatremia can be caused by adipsia and be aggravated by diabetes insipidus. Rhabdomyolysis rarely occurs. DASE REPORT: This is the first report of a diabetic patient with craniopharyngioma who developed diabetes insipidus and adipsia after surgery, evolving with severe hypernatremia that caused considerable rhabdomyolysis. CONCLUSION: The importance of the evaluation of muscle integrity when under hypernatremic states is pointed out. Although adipsia may have a simple solution through volunteer water ingestion, serious consequences such as repeated severe hypernatremia episodes and intense rhabdomyolysis with high morbidity could occur, if adipsia is not diagnosed.

A associação de diabetes insipidus e adipsia após cirurgia de craniofaringioma implica em alta morbidade. Hipernatremia pode desenvolver-se devido a adipsia e ser agravada por diabetes insipidus. Rabdomiólise raramente ocorre. DESCRIÇÃO DO CASO: Esta é a primeira descrição de paciente diabético com craniofaringioma que desenvolveu diabetes insipidus e adipsia após a cirurgia, evoluindo com hipernatremia grave e conseqüente rabdomiólise maciça. CONCLUSÃO: Ressalta-se a necessidade de avaliar a integridade muscular na vigência de estados hipernatrêmicos. Apesar de apresentar solução simples, como ingestão voluntária de água, pode haver sérias conseqüências se o diagnóstico de adipsia não é realizado, como episódios repetidos de hipernatremia grave com rabdomiólise intensa e elevada morbidade.