The performance of the MODY calculator in a non-Caucasian, mixed-race population diagnosed with diabetes mellitus before 35 years of age.

BACKGROUND: A maturity-onset diabetes of the young (MODY) calculator has been described and validated for use in European Caucasians. This study evaluated its performance in Brazilians diagnosed with diabetes mellitus (DM) before 35 years of age. METHODS: The electronic records of 391 individuals were reviewed in 2020 at the diabetes clinic of a quaternary hospital in São Paulo were analyzed: 231 with type 1 DM (T1DM), 46 with type 2 (T2DM) and 114 with MODY. The MODY calculator was applied to the three groups. A receiver operating characteristic curve was calculated to obtain cut-off points for this population. RESULTS: The principal differences between the MODY and the T1DM and T2DM groups were body mass index, a positive family history of diabetes and mean HbA1c level. Age at diagnosis in the MODY group was only significantly different compared to the T2DM group. Specificity and sensitivity were good for the cut-off points of 40%, 50% and 60%, with the accuracy of the model for any of these cut-off points being > 95%. CONCLUSION: The capacity of the calculator to identify Brazilian patients with MODY was good. Values ≥ 60% proved useful for selecting candidates for MODY genetic testing, with good sensitivity and specificity.

Genetic and clinical features of neonatal and early onset diabetes mellitus in a tertiary center cohort in Brazil.

Neonatal diabetes mellitus (NDM) is defined as the occurrence of severe hyperglycemia in infants under 6 months old and may be permanent (PNDM) or transient (TNDM). When diabetes is diagnosed at 6-12 months of age (early onset diabetes [EOD]), the etiology may be monogenic; however, most cases consist of type 1 diabetes mellitus (T1DM). Molecular diagnosis was determined in a cohort of 35 unrelated Brazilian patients with NDM or EOD based on targeted next-generation sequencing panel and/or chromosome 6q24 abnormalities. The impact of genetic testing on treatment and follow-up was evaluated. Overall, 24 patients had NDM: with 18 (75.0%) having PNDM, 5 TNDM (20.8%) and 1 case in which this information was unknown. Eleven patients had EOD. Genetic testing was positive in 20/24 patients with NDM (83.3%) and in 18.2% of cases of EOD. The commonest causes were ATP-sensitive potassium (KATP) channel genes, and GCK and IPEX mutations (37.1%, 11.4% and 5.7%, respectively). Patients with PNDM due to KCNJ11 and ABCC8 mutations transitioned successfully to sulfonylureas in almost 60% of cases, reinforcing the benefit of performing genetic testing in NDM as early as possible. This report refers to the largest series of cases of NDM (TNDM and PNDM) and EOD in Brazil in which patients were submitted to molecular investigation and in which the clinical impact of genetic diagnosis was also evaluated.

Clinical and genetic characterization and long-term evaluation of individuals with maturity-onset diabetes of the young (MODY): The journey towards appropriate treatment.

AIMS: To describe the clinical and genetic characteristics and long-term follow-up of a cohort with maturity-onset diabetes of the young (MODY), and to evaluate how molecular diagnosis impacted on treatment. METHODS: A large observational, retrospective, cohort study included individuals referred to the University of São Paulo's Monogenic Diabetes Unit between 2011 and 2020. Comprehensive clinical and genetic evaluations were performed. RESULTS: Overall, 228 individuals (190 GCK-MODY and 38 HNF1A-MODY) were enrolled. Sixty-two different GCK gene mutations (5 novel) and 17 HNF1A gene mutations (2 novel) were found. Data were available on treatment status for 76 index individuals with GCK-MODY. Before molecular diagnosis, nutritional intervention alone was used in 41 cases (53.9%). After molecular diagnosis, this number increased to 72 (94.8%). Glycated haemoglobin (HbA1c) remained stable over the 6-year follow-up period: 6.5% (47 mmol/mol) at the first and 6.3% (45 mmol/mol) at the final visit (p = 0.056). Prior to molecular diagnosis, 7/21 (33.3%) HNF1A-MODY individuals were using sulfonylurea compared to 17/21 (81%) after testing. After a median of 5 years on sulfonylureas, HbA1c values improved from 7.5% (58 mmol/mol) to 6.5% (48 mmol/mol) (p = 0.006). CONCLUSIONS: Molecular diagnosis resulted in appropriate adjustment of treatment in approximately 80% of participants with GCK-MODY or HNF1A-MODY.

Targeted massively parallel sequencing for congenital generalized lipodystrophy.

OBJECTIVE: Our aim is to establish genetic diagnosis of congenital generalized lipodystrophy (CGL) using targeted massively parallel sequencing (MPS), also known as next-generation sequencing (NGS). METHODS: Nine unrelated individuals with a clinical diagnosis of CGL were recruited. We used a customized panel to capture genes related to genetic lipodystrophies. DNA libraries were generated, sequenced using the Illumina MiSeq, and bioinformatics analysis was performed. RESULTS: An accurate genetic diagnosis was stated for all nine patients. Four had pathogenic variants in AGPAT2 and three in BSCL2. Three large homozygous deletions in AGPAT2 were identified by copy-number variant analysis. CONCLUSION: Although we have found allelic variants in only 2 genes related to CGL, the panel was able to identify different variants including deletions that would have been missed by Sanger sequencing. We believe that MPS is a valuable tool for the genetic diagnosis of multi-genes related diseases, including CGL.

Clinical and epidemiological characteristics and factors associated with mortality in adult patients admitted by COVID -19 in intensive care / Características clínicas, epidemiológicas e fatores associados à mortalidade em pacientes adultos internados por COVID -19 em unidade de terapia intensiva

Objectives: We conducted a retrospective, observational, case-control type study to define the clinical and epidemiological characteristics and factors associated with death in the intensive care of these patients. Methodology: We reviewed the medical records and examinations of 72 patients with confirmed diagnosis of SARS-CoV-2 infection in our intensive care unit (ICU). Results: In the review, 20 patients died during hospitalization, and 52 were discharged from the ICU. Associated with mortality, we verified, after analysis, that age, male gender, smoking, tropononin levels, creatinine, lymphocytes, bilirubin, and respiratory compliance were statistically significant. SOFA, APACHE 2, and SAPS 2 scores were good predictors of ICU mortality in this population. Conclusion: Despite several limitations, our study was able to demonstrate a series of clinical and laboratory factors associated with ICU death by COVID-19, compatible with international and multicenter case series.

Objetivo: Realizamos um estudo retrospectivo, observacional, tipo caso-controle com o objetivo de definir as características clínicas, epidemiológicas e fatores associados à morte em terapia intensiva desses pacientes. Metodologia: Revisamos os prontuários e exames de 72 pacientes com diagnóstico confirmado de infecção por SARS-CoV-2 em nossa unidade de terapia intensiva (UTI), realizando uma análise de fatores associados a óbito em terapia intensiva em nossa população. Resultados: Em nosso centro, 20 pacientes morreram durante o internamento, e 52 tiveram alta da UTI. Associado à mortalidade, verificamos, após análise, que idade, sexo masculino, tabagismo, níveis de tropononina, creatinina, linfócitos, bilirrubinas e complacência respiratória tiveram significância estatística. Os escores SOFA, APACHE 3 e SAPS 2 foram bons preditores de mortalidade em UTI nessa população em nosso meio. Conclusão: Apesar das várias limitações, nosso estudo conseguiu demostrar uma série de fatores clínicos e laboratoriais associados a óbito em UTI por COVID-19, compatível com séries de casos internacionais e multicêntricas.

Targeted sequencing identifies novel variants in common and rare MODY genes.

BACKGROUND: Maturity-onset diabetes of the young (MODY) is a form of monogenic diabetes with autosomal dominant inheritance. To date, mutations in 11 genes have been frequently associated with this phenotype. In Brazil, few cohorts have been screened for MODY, all using a candidate gene approach, with a high prevalence of undiagnosed cases (MODY-X). METHODS: We conducted a next-generation sequencing target panel (tNGS) study to investigate, for the first time, a Brazilian cohort of MODY patients with a negative prior genetic analysis. One hundred and two patients were selected, of which 26 had an initial clinical suspicion of MODY-GCK and 76 were non-GCK MODY. RESULTS: After excluding all benign and likely benign variants and variants of uncertain significance, we were able to assign a genetic cause for 12.7% (13/102) of the probands. Three rare MODY subtypes were identified (PDX1/NEUROD1/ABCC8), and eight variants had not been previously described/mapped in genomic databases. Important clinical findings were evidenced in some cases after genetic diagnosis, such as MODY-PDX1/HNF1B. CONCLUSION: A multiloci genetic approach allowed the identification of rare MODY subtypes, reducing the large percentage of MODY-X in Brazilian cases and contributing to a better clinical, therapeutic, and prognostic characterization of these rare phenotypes.

Searching for mutations in the HNF1B gene in a Brazilian cohort with renal cysts and hyperglycemia

ABSTRACT Objective To verify the presence of variants in HNF1B in a sample of the Brazilian population selected according to the presence of renal cysts associated with hyperglycemia. Subjects and methods We evaluated 28 unrelated patients with clinical suspicion of HNF1B mutation because of the concomitant presence of diabetes mellitus (DM) or prediabetes and renal cysts. Genotyping was accomplished using Sanger sequencing or multiplex ligation-dependent probe amplification (MLPA). In positive cases, available relatives were recruited. Results We found two patients with HNF1B mutations. The first presented the variant p.Pro328Leufs*48(c.983delC) and had DM, renal cysts, and hypomagnesemia. The second presented a heterozygous whole gene deletion in HNF1B, DM, renal cysts, body and tail pancreatic agenesis, and hypomagnesemia; this alteration was also found in his two siblings and his father. Conclusion The recruitment of suspected cases of HNF1B gene mutations in Brazilians due to hyperglycemia and renal cysts presents two positive cases. Our cases contribute to the annotation of clinical and biochemical phenotypes of this rare form of maturity-onset diabetes of the young (MODY).

Searching for mutations in the HNF1B gene in a Brazilian cohort with renal cysts and hyperglycemia.

OBJECTIVE: To verify the presence of variants in HNF1B in a sample of the Brazilian population selected according to the presence of renal cysts associated with hyperglycemia. SUBJECTS AND METHODS: We evaluated 28 unrelated patients with clinical suspicion of HNF1B mutation because of the concomitant presence of diabetes mellitus (DM) or prediabetes and renal cysts. Genotyping was accomplished using Sanger sequencing or multiplex ligation-dependent probe amplification (MLPA). In positive cases, available relatives were recruited. RESULTS: We found two patients with HNF1B mutations. The first presented the variant p.Pro328Leufs*48(c.983delC) and had DM, renal cysts, and hypomagnesemia. The second presented a heterozygous whole gene deletion in HNF1B, DM, renal cysts, body and tail pancreatic agenesis, and hypomagnesemia; this alteration was also found in his two siblings and his father. CONCLUSION: The recruitment of suspected cases of HNF1B gene mutations in Brazilians due to hyperglycemia and renal cysts presents two positive cases. Our cases contribute to the annotation of clinical and biochemical phenotypes of this rare form of maturity-onset diabetes of the young (MODY).

Pitfalls in the diagnosis of insulin autoimmune syndrome (Hirata's disease) in a hypoglycemic child: a case report and review of the literature.

Background Insulin autoimmune syndrome (IAS) is a rare cause of hyperinsulinemic hypoglycemia (HH) not addressed as a potential differential diagnosis in current pediatric guidelines. We present a case of IAS in a child with no previous history of autoimmune disease, no previous intake of triggering medications and absence of genetic predisposition. Case presentation A 6-year-old boy presented with recurrent HH (blood glucose of 26 mg/dL [1.4 mmol/L] and insulin of 686 µU/mL). Abdominal imaging was normal. After multiple therapeutic failures, we hypothesized misuse of exogenous insulin and factitious hypoglycemia. Council of Guardianship had the child separated from his mother, but insulin levels remained high. A chromatography test was then performed which showed high titers of endogenous insulin autoantibody (IAA) with early dissociation from the insulin molecule. The human leukocyte antigen (HLA) test showed a DRB1 *13:01/*08:02 genotype. The patient was advised to control food intake and physical activity routines. During a 5-year follow-up, hypoglycemic episodes were sparse, despite high insulin levels. Conclusions Misdiagnosis of IAS with factitious hypoglycemia may happen if IAS is not considered as a differential diagnosis, leading to potential traumatic consequences. Further efforts should be made to increase awareness of IAS as a differential diagnosis of hypoglycemia and to include it in pediatric guidelines.

Acquired Lipodystrophy Associated With Nivolumab in a Patient With Advanced Renal Cell Carcinoma.

CONTEXT: Lipodystrophy syndromes are rare disorders characterized by the selective loss of adipose tissue. We aimed to report a case of acquired generalized lipodystrophy possibly associated with nivolumab. CASE DESCRIPTION: A woman was referred to our Endocrinology Department for uncontrolled diabetes mellitus. At 50 years of age, she was diagnosed with type 2 diabetes after a routine laboratory test and her diabetes was well controlled with low doses of metformin. In 2010, she was diagnosed with clear cell renal carcinoma. The cancer progressed in the following years, leading to the initiation of treatment with nivolumab in 2017. Two months later she presented with facial lipoatrophy, with loss of the buccal fat pads and prominent zygomatic arch. Her neck, shoulders, arms, and buttocks were also affected. Her diabetes control worsened. She received maximal doses of metformin and pioglitazone and was administered 1.5 units/kg/d insulin. Subcutaneous biopsy of medial surface of the arm revealed chronic lobular panniculitis. Despite nivolumab's possible involvement in the onset of lipodystrophy, the maintenance of nivolumab therapy was justified by the observed reduction in the progression of the cancer, combined with the lack of an alternative chemotherapy. The therapy was withdrawn after 8 months of treatment because of grade 3 hepatitis. CONCLUSION: Anti-PD1 therapy has great potential. Early recognition of the onset of unusual collateral effects is important to improve decision making regarding the treatment of patients with tumors.

Homozygous and Heterozygous Nuclear Lamin A p.R582C Mutation: Different Lipodystrophic Phenotypes in the Same Kindred.

Background: Dunnigan-type familial partial lipodystrophy (FPLD2) is a rare autosomal dominant disease caused by heterozygous mutations in the LMNA gene that results in regional loss of subcutaneous adipose tissue with onset in puberty. However, a generalized lipodystrophy phenotype has also been associated with heterozygous mutations in this gene, demonstrating the noticeable phenotypic heterogeneity of this disease. Methods: We report and describe clinical and metabolic features of four patients from the same family with the p.R582C LMNA mutation, three homozygous and one in the heterozygous state that present with three distinct lipodystrophic phenotypes. Results: Case description: The proband was a 12-year-old girl who developed severe subcutaneous fat atrophy in limbs and abdomen followed by a remarkable dorsocervical fat accumulation in adulthood along with diabetes at age 23. The proband's sister was a phenotypically normal girl who developed hypertriglyceridemia at age 8, progressive features of partial lipodystrophy at age 11, and diabetes at age 22. The proband's mother was first examined at age 32, presenting diabetes and a severe generalized lipodystrophic phenotype; she developed kidney failure at age 41 and died due to diabetic complications. The proband's father was a 50-year-old man with abdominal fat concentration that was initially considered phenotypically normal. Massively parallel sequencing using a platform of genes related to genetic lipodystrophies, followed by Sanger sequencing, revealed the transversion c.1744C>T at exon 11 of the LMNA gene (p.R582C) in the homozygous (mother and daughters) and heterozygous (father) states. Conclusion: We documented three distinct phenotypes of the homozygous and heterozygous p. R582C LMNA mutation in the same kindred, illustrating that FPLD2 linked to mutations in this gene is a disease of great clinical heterogeneity, possibly due to associated environmental or genetic factors.

A Novel Generalized Lipodystrophy-Associated Progeroid Syndrome Due to Recurrent Heterozygous LMNA p.T10I Mutation.

Background: Lamin A/C (LMNA) gene mutations cause a heterogeneous group of progeroid disorders, including Hutchinson-Gilford progeria syndrome, mandibuloacral dysplasia, and atypical progeroid syndrome (APS). Five of the 31 previously reported patients with APS harbored a recurrent de novo heterozygous LMNA p.T10I mutation. All five had generalized lipodystrophy, as well as similar metabolic and clinical features, suggesting a distinct progeroid syndrome. Methods: We report nine new patients and follow-up of two previously reported patients with the heterozygous LMNA p.T10I mutation and compare their clinical and metabolic features with other patients with APS. Results: Compared with other patients with APS, those with the heterozygous LMNA p.T10I mutation were younger in age but had increased prevalence of generalized lipodystrophy, diabetes mellitus, acanthosis nigricans, hypertriglyceridemia, and hepatomegaly, together with higher fasting serum insulin and triglyceride levels and lower serum leptin and high-density lipoprotein cholesterol levels. Prominent clinical features included mottled skin pigmentation, joint contractures, and cardiomyopathy resulting in cardiac transplants in three patients at ages 13, 33, and 47 years. Seven patients received metreleptin therapy for 0.5 to 16 years with all, except one noncompliant patient, showing marked improvement in metabolic complications. Conclusions: Patients with the heterozygous LMNA p.T10I mutation have distinct clinical features and significantly worse metabolic complications compared with other patients with APS as well as patients with Hutchinson-Gilford progeria syndrome. We propose that they be recognized as having generalized lipodystrophy-associated progeroid syndrome. Patients with generalized lipodystrophy-associated progeroid syndrome should undergo careful multisystem assessment at onset and yearly metabolic and cardiac evaluation, as hyperglycemia, hypertriglyceridemia, hepatic steatosis, and cardiomyopathy are the major contributors to morbidity and mortality.

Maturity-onset diabetes of the young (MODY) in Brazil: Establishment of a national registry and appraisal of available genetic and clinical data.

AIMS: Maturity-Onset Diabetes of the Young (MODY) comprises a heterogeneous group of monogenic forms of diabetes caused by mutations in at least 14 genes, but mostly by mutations in Glucokinase (GCK) and hepatocyte nuclear factor-1 homeobox A (HNF1A). This study aims to establish a national registry of MODY cases in Brazilian patients, assessing published and unpublished data. METHODS: 311 patients with clinical characteristics of MODY were analyzed, with unpublished data on 298 individuals described in 12 previous publications and 13 newly described cases in this report. RESULTS: 72 individuals had GCK mutations, 9 described in Brazilian individuals for the first time. One previously unpublished novel GCK mutation, Gly178Ala, was found in one family. 31 individuals had HNF1A mutations, 2 described for the first time in Brazilian individuals. Comparisons of GCK probands vs HNF1A: age 16±11 vs 35±20years; age at diagnosis 11±8 vs 21±7years; BMI 19±6 vs 25±6kg/m2; sulfonylurea users 5 vs 83%; insulin users 5 vs 17%; presence of arterial hypertension 0 vs. 33%, all p<0.05. No differences were observed in lipids and C-peptide. CONCLUSIONS: Most MODY cases in Brazil are due to GCK mutations. In agreement with other studied populations, novel mutations are common. Only 14% of patients with familial diabetes carry a HNF1A mutation. Diagnosis of other rare forms of MODY is still a challenge in Brazilian population, as well as adequate strategies to screen individuals for molecular diagnosis.

Central precocious puberty that appears to be sporadic caused by paternally inherited mutations in the imprinted gene makorin ring finger 3.

CONTEXT: Loss-of-function mutations in makorin ring finger 3 (MKRN3), an imprinted gene located on the long arm of chromosome 15, have been recognized recently as a cause of familial central precocious puberty (CPP) in humans. MKRN3 has a potential inhibitory effect on GnRH secretion. OBJECTIVES: The objective of the study was to investigate potential MKRN3 sequence variations as well as copy number and methylation abnormalities of the 15q11 locus in patients with apparently sporadic CPP. SETTING AND PARTICIPANTS: We studied 215 unrelated children (207 girls and eight boys) from three university medical centers with a diagnosis of CPP. All but two of these patients (213 cases) reported no family history of premature sexual development. First-degree relatives of patients with identified MKRN3 variants were included for genetic analysis. MAIN OUTCOME MEASURES: All 215 CPP patients were screened for MKRN3 mutations by automatic sequencing. Multiplex ligation-dependent probe amplification was performed in a partially overlapping cohort of 52 patients. RESULTS: We identified five novel heterozygous mutations in MKRN3 in eight unrelated girls with CPP. Four were frame shift mutations predicted to encode truncated proteins and one was a missense mutation, which was suggested to be deleterious by in silico analysis. All patients with MKRN3 mutations had classical features of CPP with a median age of onset at 6 years. Copy number and methylation abnormalities at the 15q11 locus were not detected in the patients tested for these abnormalities. Segregation analysis was possible in five of the eight girls with MKRN3 mutations; in all cases, the mutation was inherited on the paternal allele. CONCLUSIONS: We have identified novel inherited MKRN3 defects in children with apparently sporadic CPP, supporting a fundamental role of this peptide in the suppression of the reproductive axis.

Molecular and gene network analysis of thyroid transcription factor 1 (TTF1) and enhanced at puberty (EAP1) genes in patients with GnRH-dependent pubertal disorders.

BACKGROUND/AIM: TTF1 and EAP1 are transcription factors that modulate gonadotropin-releasing hormone expression. We investigated the contribution of TTF1 and EAP1 genes to central pubertal disorders. PATIENTS AND METHODS: 133 patients with central pubertal disorders were studied: 86 with central precocious puberty and 47 with normosmic isolated hypogonadotropic hypogonadism. The coding region of TTF1 and EAP1 were sequenced. Variations of polyglutamine and polyalanine repeats in EAP1 were analyzed by GeneScan software. Association of TTF1 and EAP1 to genes implicated in timing of puberty was investigated by meta-network framework GeneMANIA and Cytoscape software. RESULTS: Direct sequencing of the TTF1 did not reveal any mutation or polymorphisms. Four EAP1 synonymous variants were identified with similar frequencies among groups. The most common EAP1 5'-distal polyalanine genotype was the homozygous 12/12, but the genotype 12/9 was identified in 2 central precocious puberty sisters without functional alteration in EAP1 transcriptional activity. TTF1 and EAP1 were connected, via genetic networks, to genes implicated in the control of menarche. CONCLUSION: No TTF1 or EAP1 germline mutations were associated with central pubertal disorders. TTF1 and EAP1 may affect puberty by changing expression in response to other members of puberty-associated gene networks, or by differentially affecting the expression of gene components of these networks.

Incidental mild hyperglycemia in children: two MODY 2 families identified in Brazilian subjects / Hiperglicemia incidental em crianças: duas famílias com MODY 2 identificadas em brasileiros

Maturity-onset diabetes of the young (MODY) is characterized by an autosomal dominant mode of inheritance, early onset of hyperglycemia, and defects of insulin secretion. MODY subtypes described present genetic, metabolic, and clinical differences. MODY 2 is characterized by mild asymptomatic fasting hyperglycemia, and rarely requires pharmacological treatment. Hence, precise diagnosis of MODY is important for determining management and prognosis. We report two heterozygous GCK mutations identified during the investigation of short stature. Case 1: a prepubertal 14-year-old boy was evaluated for constitutional delay of growth and puberty. During follow-up, he showed abnormal fasting glucose (113 mg/dL), increased level of HbA1c (6.6%), and negative β-cell antibodies. His father and two siblings also had slightly elevated blood glucose levels. The mother had normal glycemia. A GCK heterozygous missense mutation, p.Arg191Trp, was identified in the proband. Eighteen family members were screened for this mutation, and 11 had the mutation in heterozygous state. Case 2: a 4-year-old boy investigated for short stature revealed no other laboratorial alterations than elevated glycemia (118 mg/dL); β-cell antibodies were negative. His father, a paternal aunt, and the paternal grandmother also had slightly elevated glycemia, whereas his mother had normal glycemia. A GCK heterozygous missense mutation, p.Glu221Lys, was identified in the index patient and in four family members. All affected patients had mild elevated glycemia. Individuals with normal glycemia did not harbor mutations. GCK mutation screening should be considered in patients with chronic mild early-onset hyperglycemia, family history of impaired glycemia, and negative β-cell antibodies. Arq Bras Endocrinol Metab. 2012;56(8):519-24.

O diabetes do tipo MODY (maturity-onset diabetes of the young) caracteriza-se por herança autossômica dominante, início precoce da hiperglicemia e defeitos na secreção de insulina. Os subtipos de MODY apresentam diferenças genéticas, metabólicas e clínicas. O MODY 2 é caracterizado por hiperglicemia leve assintomática e raramente requer tratamento farmacológico. O diagnóstico preciso de MODY é importante para se determinar o tratamento e o prognóstico. Relatamos duas mutações no gene GCK em heterozigose identificadas durante investigação de baixa estatura. Caso 1: paciente do sexo masculino, com 14 anos, pré-púbere, avaliado por atraso constitucional do crescimento e da puberdade. Durante o acompanhamento, apresentou glicemia de jejum alterada (113 mg/dL), aumento de HbA1c (6,6%) e anticorpos anticélulas β negativos. Seu pai e dois irmãos também apresentavam glicemia levemente elevada. A mãe tinha glicemia normal. Foi identificada no gene GCK uma mutação missense em heterozigose, p.Arg191Trp. Dezoito membros da família foram rastreados e 11 apresentavam essa mutação. Caso 2: paciente do sexo masculino, com 4 anos, em avaliação por baixa estatura. Não apresentou alterações laboratoriais, exceto por glicemia elevada (118 mg/dL). Anticorpos anticélulas β foram negativos. Seu pai, uma tia paterna e a avó paterna também apresentavam glicemia discretamente elevada, e a mãe, glicemia normal. A mutação missense em heterozigose, p.Glu221Lys, foi identificada no paciente-índice e em 4 membros da família. Todos os pacientes afetados apresentavam hiperglicemia leve. Essas mutações não foram identificadas nos indivíduos com glicemia normal. O rastreamento de mutações no gene GCK deve ser considerado em pacientes com hiperglicemia crônica leve e de início precoce, história familiar de glicemia elevada e anticorpos anticélulas β negativos. Arq Bras Endocrinol Metab. 2012;56(8):519-24.

Cyclosporin safety in a simplified rat brain tumor implantation model.

Brain cancer is the second neurological cause of death. A simplified animal brain tumor model using W256 (carcinoma 256, Walker) cell line was developed to permit the testing of novel treatment modalities. Wistar rats had a cell tumor solution inoculated stereotactically in the basal ganglia (right subfrontal caudate). This model yielded tumor growth in 95% of the animals, and showed absence of extracranial metastasis and systemic infection. Survival median was 10 days. Estimated tumor volume was 17.08 ± 6.7 mm(3) on the 7(th) day and 67.25 ± 19.8 mm(3) on 9(th) day post-inoculation. Doubling time was 24.25 h. Tumor growth induced cachexia, but no hematological or biochemical alterations. This model behaved as an undifferentiated tumor and can be promising for studying tumor cell migration in the central nervous system. Dexamethasone 3.0 mg/kg/day diminished significantly survival in this model. Cyclosporine 10 mg/kg/day administration was safely tolerated.

Cyclosporin safety in a simplified rat brain tumor implantation model / Segurança do tratamento com ciclosporina em um modelo pré-clínico de tumor cerebral experimental em ratos

Brain cancer is the second neurological cause of death. A simplified animal brain tumor model using W256 (carcinoma 256, Walker) cell line was developed to permit the testing of novel treatment modalities. Wistar rats had a cell tumor solution inoculated stereotactically in the basal ganglia (right subfrontal caudate). This model yielded tumor growth in 95 percent of the animals, and showed absence of extracranial metastasis and systemic infection. Survival median was 10 days. Estimated tumor volume was 17.08±6.7 mm³ on the 7th day and 67.25±19.8 mm³ on 9th day post-inoculation. Doubling time was 24.25 h. Tumor growth induced cachexia, but no hematological or biochemical alterations. This model behaved as an undifferentiated tumor and can be promising for studying tumor cell migration in the central nervous system. Dexamethasone 3.0 mg/kg/day diminished significantly survival in this model. Cyclosporine 10 mg/kg/day administration was safely tolerated.

Neoplasias encefálicas constituem a segunda causa neurológica de morte. Foi desenvolvido um modelo animal simplificado de tumor cerebral em ratos utilizando a linhagem celular W256 (carcinoma 256 de Walker) para permitir teste de novos tratamentos. Ratos Wistar foram inoculados nos gânglios da base (caudato subfrontal direito) com uma solução celular tumoral, por via estereotáxica. Este modelo demonstrou crescimento tumoral em 95 por cento dos animais inoculados com sucesso, além de mostrar ausência de metástases extracranianas e infecção sistêmica. A mediana de sobrevida dos animais foi de 10 dias. O volume tumoral estimado foi de 17,08±6,7 mm³ no sétimo dia e de 67,25±19,8 mm³ no nono dia após a inoculação. O tempo de duplicação foi estimado em 24,25 h. O crescimento tumoral induziu a caquexia, mas não houve alterações bioquímicas ou hematológicas. Esse modelo permite fácil reprodução e comporta-se como um tumor indiferenciado, mostrando potencial para estudar migração celular tumoral no sistema nervoso central. Dexametasona 3,0 mg/kg/dia reduziu significantemente a sobrevida dos animais inoculados com tumor nesse modelo. Ciclosporina 10 mg/kg/dia não teve efeito na sobrevida, sendo sua administração bem tolerada.

Incidental mild hyperglycemia in children: two MODY 2 families identified in Brazilian subjects.

Maturity-onset diabetes of the young (MODY) is characterized by an autosomal dominant mode of inheritance, early onset of hyperglycemia, and defects of insulin secretion. MODY subtypes described present genetic, metabolic, and clinical differences. MODY 2 is characterized by mild asymptomatic fasting hyperglycemia, and rarely requires pharmacological treatment. Hence, precise diagnosis of MODY is important for determining management and prognosis. We report two heterozygous GCK mutations identified during the investigation of short stature. Case 1: a prepubertal 14-year-old boy was evaluated for constitutional delay of growth and puberty. During follow-up, he showed abnormal fasting glucose (113 mg/dL), increased level of HbA1c (6.6%), and negative ß-cell antibodies. His father and two siblings also had slightly elevated blood glucose levels. The mother had normal glycemia. A GCK heterozygous missense mutation, p.Arg191Trp, was identified in the proband. Eighteen family members were screened for this mutation, and 11 had the mutation in heterozygous state. Case 2: a 4-year-old boy investigated for short stature revealed no other laboratorial alterations than elevated glycemia (118 mg/dL); ß-cell antibodies were negative. His father, a paternal aunt, and the paternal grandmother also had slightly elevated glycemia, whereas his mother had normal glycemia. A GCK heterozygous missense mutation, p.Glu221Lys, was identified in the index patient and in four family members. All affected patients had mild elevated glycemia. Individuals with normal glycemia did not harbor mutations. GCK mutation screening should be considered in patients with chronic mild early-onset hyperglycemia, family history of impaired glycemia, and negative ß-cell antibodies.