Fructosamine and glycated hemoglobin as biomarkers of glycemic control in people with type 2 diabetes mellitus and cancer (GlicoOnco study)

Abstract Introduction Glycemic control is important to avoid diabetes complications in individuals with cancer. There is no evidence for HbA1c and fructosamine as reliable biomarkers in these conditions. There are particularities in caring for patients with diabetes and cancer that can alter these biomarkers. Objective The aim of this study was to evaluate HbA1c and fructosamine as glycemic biomarkers in people with type 2 diabetes and cancer, undergoing clinical or surgical oncological treatment. Methods The authors conducted a single-center, retrospective analysis with people who have cancer and diabetes. Comparison of glycemic biomarkers (HbA1c, fructosamine, and Self-Monitoring of Blood Glucose [SMBG]) was performed including evaluation in individuals undergoing chemotherapy, using glucocorticoids, with anemia, hypoproteinemia or with reduced estimated Glomerular Filtration Rate (eGFR). Results There was a strong positive correlation between fructosamine and HbA1c (n = 318, r= 0.66, p < 0.001) in people with diabetes and cancer even in those under chemotherapy (n = 101, r= 0.61, p < 0.001) or using glucocorticoids (n = 96, r= 0.67, p<0.001). There was a strong correlation between HbA1c and fructosamine in subjects with anemia (n = 111, r= 0.66, p < 0.001), hypoproteinemia (n = 54, r= 0.67, p < 0.001), or with eGFR ≥ 60 mL/min/1.73 m2 (n = 189, r= 0.70, p < 0.001), and moderate correlation with hypoalbuminemia (n = 21, r= 0.54, p = 0.001) and with reduced eGFR (n = 67, r= 0.57, p < 0.001). The correlations between fructosamine and HbA1c with SMBG were moderate (n = 164, r= 0.49, p < 0.001; n = 111, r= 0.55, p < 0.001, respectively), strong in subjects undergoing chemotherapy, with hypoalbuminemia or hypoproteinemia, and at least moderate, if eGFR < 60 mL/min/1.73 m2 or with anemia. Conclusions Fructosamine and HbA1c can be used as glycemic biomarkers in people with diabetes and cancer, even in those with anemia, hypoproteinemia, or undergoing chemotherapy.

Effects of glucocorticoids on interstitial glucose concentrations in individuals with hematologic cancer and without known diagnosis of diabetes: a pilot study

ABSTRACT Objective To analyze interstitial glucose behavior during glucocorticoid use in non-diabetic patients receiving chemotherapy for hematologic malignancies. Methods Prospective pilot study carried out to assess interstitial glucose levels in 15 non-diabetic individuals with hematologic malignancies who received glucocorticoids in combination with chemotherapy. The FreeStyle Libre flash monitoring system (Abbott Diabetes Care) was used for up to 14 days to measure interstitial glucose. Results Median age and body mass index were 53 (42-61) years and 25 (23-28) kg/m2 respectively. Interstitial glucose levels >180mg/dL lasting at least one hour were detected in 60% of participants. Interstitial glucose profile parameters (median and peak interstitial glucose levels and percentage of time during which interstitial glucose levels were >180mg/dL) were significantly (p<0.01) higher during glucocorticoid use (115mg/dL, 218mg/dL and 10% respectively) than after glucocorticoid discontinuation (97mg/dL, 137mg/dL and 0% respectively). Mean interstitial glucose levels increased in the afternoon and at night during glucocorticoid use. Conclusion This pilot study was the first to evaluate interstitial glucose levels in non-diabetic individuals using glucocorticoids in treatment of hematologic cancer. Glucocorticoid use during chemotherapy significantly increases interstitial glucose levels in these patients.

Avanços na etiologia, no diagnóstico e no tratamento da puberdade precoce central / Advances in the etiology, diagnosis and treatment of central precocious puberty

O início da puberdade caracteriza-se pelo aumento de amplitude e frequência dos pulsos do hormônio secretor de gonadotrofinas (GnRH) após um período de relativa supressão hormonal durante a infância. A reemergência da secreção pulsátil do GnRH resulta em aumento na secreção de gonadotrofinas, hormônio luteinizante (LH) e folículo estimulante (FSH), pela hipófise anterior e consequente ativação gonadal. A ativação prematura do eixo hipotálamo-hipófise-gonadal resulta em puberdade precoce dependente de gonadotrofinas, também conhecida como puberdade precoce central (PPC), e se caracteriza pelo desenvolvimento dos caracteres sexuais secundários antes dos 8 anos nas meninas e 9 anos nos meninos. O início do desenvolvimento puberal provém da interação complexa de fatores genéticos, nutricionais, ambientais e socioeconômicos. O diagnóstico clínico da PPC baseia-se em reconhecimento de desenvolvimento puberal progressivo, concentrações púberes de LH em condição basal e/ou após estímulo com GnRH e avanço de idade óssea. A ressonância magnética de encéfalo é útil no estabelecimento de diagnóstico diferencial entre as formas orgânica ou idiopática. Os análogos de GnRH de ação prolongada representam o tratamento de escolha da PPC. O componente genético da PPC foi recentemente fortalecido pela evidência de mutações no gene MKRN3, localizado no braço longo do cromossomo 15, em crianças com PPC familial. Nessa revisão, dados clínicos e terapêuticos da PPC serão amplamente discutidos, visando à atualização e à conduta criteriosa dessa condição clínica de grande relevância na endocrinologia pediátrica.

The onset of puberty is first detected as an increase in the amplitude and frequency of pulses of gonadotropin-releasing hormone (GnRH) after a quiescent period during childhood. The reemergence of pulsatile GnRH secretion leads to increases in the secretion of the gonadotropins, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) by the pituitary gland, and the consequent activation of gonadal function. Early activation of the hypothalamic–pituitary–gonadal axis results in gonadotropin-dependent precocious puberty, also known as central precocious puberty (CPP), which is clinically defined by the development of secondary sexual characteristics before the age of 8 years in girls and 9 years in boys. Pubertal timing is influenced by complex interactions among genetic, nutritional, environmental, and socioeconomic factors. CPP is diagnosed on the basis of clinical signs of progressive pubertal development before the age of 8 years in girls and 9 years in boys, pubertal basal and/or GnRH-stimulated LH levels, and advanced bone age. Magnetic resonance imaging of the central nervous system is essential for establishing the CPP form as organic or idiopathic. Depot GnRH-analogues represent the first-line of therapy in CPP. Very recently, the genetic component of CPP was demonstrated by the evidence that the deficiency of the MKRN3 gene, located on long arm of chromosome 15, causes familial CPP in humans. In this current review, clinical and therapeutic aspects of the CPP will be discussed, contributing to adequate diagnosis and criterious approach of this relevant condition of pediatric endocrinology.

Síndrome de Nelson: relato de caso / Nelson's Syndrome: a case report

O objetivo deste artigo é apresentar e discutir alguns aspectos da patogênese, do diagnóstico clínico, hormonal e radiológico e do tratamento da síndrome de Nelson, com base no relato de um paciente típico portador da doença, no qual várias abordagens terapêuticas mostraram-se ineficazes.

The aim of this article is to present and discuss several aspects of the pathogenesis, the clinical, hormonal, and imaging diagnosis, and the treatment of Nelson's syndrome, based on a typical patient's report, in whom several therapeutic approaches were shown to be ineffective.

Use of nonradioactive labeling to detect large gene rearrangements in 21-hydroxylase deficiency

OBJETIVO: Padronizar a técnica de Southern blotting usando hibridização com material não radioativo para detectar grandes rearranjos no gene CYP21A2 em uma amostra da população brasileira com hiperplasia adrenal congênita. MÉTODO: Foram estudados 42 pacientes, 2 dos quais aparentados, totalizando 80 alelos não relacionados. As amostras de DNA foram obtidas de sangue periférico, digeridas com enzima de restrição Taq I, realizado Southern blotting e hibridizadas com sonda marcada com biotina. RESULTADOS: O método se mostrou eficaz, com resultados similares aos encontrados ao utilizar a metodologia com material radioativo. Foram encontradas 2,5% de deleção do CYP21A2, 8,8% de grandes conversões, 3,8% de deleção do CYP21A1P e 6,3% de duplicação do CYP21A1P. Estas freqüências foram similares às encontradas em nosso estudo prévio, onde um número significante de casos foi estudado. Um bom padrão de hibridização foi alcançado utilizando menor quantidade de DNA (5mg) e a emissão de sinais foi observada entre 5 minutos e 1 hora de exposição. CONCLUSÕES: Padronizamos uma técnica de Southern blotting/ hibridização com material não radioativo (biotina) para a pesquisa de grandes rearranjos no gene CYP21A2 com bons resultados. Apesar de ser mais trabalhoso, este método é mais rápido, utiliza menores quantidades de DNA e, principalmente, evita problemas com o uso de radioatividade.