Browsing by Author "Sequeira, Sílvia"
Now showing 1 - 10 of 17
Results Per Page
Sort Options
- Atypical adult-onset methylmalonic acidemia and homocystinuria presenting as hemolytic uremic syndromePublication . Navarro, David; Azevedo, Ana; Sequeira, Sílvia; Ferreira, Ana Carina; Carvalho, Fernanda; Fidalgo, Teresa; Vilarinho, Laura; Santos, Maria Céu; Calado, Joaquim; Nolasco, FernandoThrombotic microangiopathy (TMA) syndromes can be secondary to a multitude of different diseases. Most can be identified with a systematic approach and, when excluded, TMA is generally attributed to a dysregulation in the activity of the complement alternative pathways-atypical hemolytic uremic syndrome (aHUS). We present a challenging case of a 19-year-old woman who presented with thrombotic microangiopathy, which was found to be caused by methylmalonic acidemia and homocystinuria, a rare vitamin B12 metabolism deficiency. To our knowledge, this is the first time that an adult-onset methylmalonic acidemia and homocystinuria presents as TMA preceding CNS involvement.
- Biochemical and molecular heterogeneity in carnitine palmitoyltransferase ii deficiencyPublication . Sousa, Carmen; Fonseca, Helena; Rocha, Hugo; Marcão, Ana; Vilarinho, Laura; Diogo, Luísa; Sequeira, Sílvia; Costa, Cristina; Leão, Elisa; Conceição, Isabel; Gaspar, AnaIntroduction: Carnitine palmitoytransferase II (CPTII) deficiency is a recessively inherited disorder of lipid metabolism. CPT II deficiency has several clinical presentations: the adult form is characterized by episodes of rhabdomyolysis, usually triggered by extensive exercice, cold, fever or prolonged fasting and the infantile-type CPT II hepatocardiomuscular form presents as severe attacks of hypoketotic, hypoglycemia, occasionally associated with cardiac damage. Molecular analysis of CPT II gene allows not only confirmation of classical forms, with typical biochemical abnormalities, but is also key for the diagnosis of less severe forms.The authors will present biochemical and molecular findings of eight CPT II, patients. Material and methods: Acylcarnitine profiles, on dried blood spots, were done as previously reported (Vilarinho et al) Molecular analysis of CPT II gene was done by direct sequencing as reported elsewhere (Finocchiaro et al.). From the eight patients, three were detected through newborn screening and five with clinical symptoms. Results: More pronounced abnormalities in the acylcarnitine profiles are associated with neonatal forms of the disease, while the patients with late onset forms present smother alterations or completely normal profiles. This biochemical heterogeneity correlates well with genetics data. The molecular analysis revealed the presence of ten different mutations, which seven were never reported. Discussion: Our results support that newborn screening can efficiently detect infantile CPT II deficiency but is less effective in detecting adult forms, were biochemical abnormalities may only be present during acute episodes. In these cases accurate clinical characterization alongside with molecular analysis are the key for diagnosis. Bibliography: J.P. Bonnefont, F. et al (2004) Mol. Aspects Med. 25 495–520. Rashed MS, et al.(1995) Diagnosis of inborn errors of metabolism from blood spots by acylcarnitines and amino acids profiling using automated electrospray tandem mass spectrometry. Pediatr Res.38:324–331 Finocchiaro, G. et al (1991). cDNA cloning, sequence analysis, and chomosomal localization of the gene for human carnitinepalmitoyltransferase. Proc. Natl. Acad. Sci. USA 88, 661–665. K. Gempel1 et al. (2002).Screening for Carnitine Palmitoyltransferase II Deficiency by Tandem Mass Spectrometry Anichini A.et al(2011) Genotype-phenotype correlations in a large series of patients with muscle type CPT II deficiency Vilarinho et al. (2009) Four Years of Expanded Newborn Screening in Portugal with MS/MS
- Colesterol Total, nem oito(enta) nem (duzentos e) oitenta: Parte 2 – Hipolipidemias primárias – alterações do metabolismo das lipoproteínasPublication . Alves, Ana Catarina; Sequeira, Sílvia; Cardoso, Maria Luís; Moldovan, Oana; Espírito Santo, Raquel; Oliveira, Renata; Guerra, António; Bourbon, MafaldaA dislipidemia é um distúrbio do perfil lipídico, seja por elevação ou diminuição de uma ou mais partículas lipídicas. O objetivo deste trabalho é fazer uma revisão das causas moleculares de hipolipidemias e suas consequências clínicas. São também apresentados casos com hipolipidemias raras já estudados, ou com estudo em curso no laboratório do INSA, apresentando os dados clínicos e moleculares mais relevantes. O perfil lipídico foi determinado por métodos automatizados para cada caso índex e familiares e o estudo molecular dos genes envolvidos foi realizado por amplificação por PCR e sequenciação de Sanger ou sequenciação de nova geração (NGS). Foram referenciados ao laboratório do INSA 7 casos índex, tendo sido possível até ao momento identificar a causa molecular do fenótipo apresentado em 3 casos: 2 com hipobetalipoproteinemia (1 homozigoto e 1 heterozigoto) e 1 caso índex com doença de Tangier; os restantes encontram se ainda em estudo. Doentes com as dislipidemias raras apresentadas têm um risco elevado de ter complicações cardiovasculares, neurológicas e/ou esteatose hepática e devem, por esta razão, ser identificados o mais precocemente possível, de forma a minimizar ou prevenir os efeitos nefastos destas condições.
- Diagnóstico das Doenças Mitocondriais por Sequenciação de Nova GeraçãoPublication . Nogueira, Célia; Pereira, Cristina; Silva, Lisbeth; Rodrigues, Esmeralda; Janeiro, Patricia; Sequeira, Sílvia; Santos, Helena; Martins, Esmeralda; Vilarinho, Laura; Vieira, Luis; Leão Teles, Elisa; Campos, Teresa; Costa, Cláudia; Gaspar, Ana; Dupont, Juliette; Soares, Gabriela; Bandeira, Anabela; Magalhães, Marina; Vieira, José PedroIntrodução e objetivos: As doenças mitocondriais constituem um importante grupo de doenças metabólicas de expressão clínica heterogénea, para as quais não existe uma terapia eficaz. Estas patologias podem ser causadas por defeitos genéticos quer no genoma mitocondrial, quer no nuclear. A sequenciação de nova geração (NGS) revolucionou o diagnóstico molecular destas doenças, uma vez que tem capacidade de gerar uma enorme quantidade de dados num curto espaço de tempo a um custo acessível. O objetivo deste estudo [Financiado pela FCT (PTDC/DTP-PIC/2220/2014) e pelo Norte 2020 (NORTE-01-0246-FEDER-000014)] é desenvolver uma estratégia de NGS para permitir o diagnóstico genético de doentes suspeitos de doenças mitocondriais.
- Estudo de dislipidemias familiares monogénicas rarasPublication . Alves, Ana Catarina; Sequeira, Sílvia; Moldovan, Oana; Lobarinhas, Goreti; Mansilha, Helena; Duarte, Sequeira; Gaspar, Ana; Guerra, António; Bourbon, MafaldaA dislipidemia é um distúrbio do perfil lipídico, seja por elevação ou diminuição de partículas lipídicas. O objetivo deste trabalho é fazer uma revisão dos casos com dislipidemia rara em estudo no Instituto Nacional de Saúde Doutor Ricardo Jorge, apresentando os dados clínicos e moleculares mais relevantes. O perfil lipídico foi determinado para cada caso índex e familiares e o estudo molecular dos genes envolvidos foi realizado por amplificação por PCR e sequenciação de Sanger. Foram estudados, ou está em curso o estudo, de 14 casos índex com os seguintes diagnósticos clínicos: Deficiência familiar em lipoproteína lípase (3), Lipodistrofia familiar parcial de Dunningan Tipo 2 (1), Deficiência em lípase ácida lisossomal (3), Abeta/hipobetalipoproteinemia (2), Deficiência em HDL (1), Hipertrigliceridemia autossómica recessiva (3), Sitosterolemia (1). O fenótipo clínico de cada caso índex é variável dependendo de cada condição. Foi encontrada a causa genética da doença em 8/14 doentes, estando os restantes ainda em estudo. Doentes com as várias dislipidemias raras apresentadas têm um risco acrescido de ter outras doenças graves como pancreatite, doença cardiovascular ou complicações neurológicas e devem, por esta razão, ser identificados o mais precocemente possível, de forma a minimizar ou prevenir os efeitos nefastos destas condições.
- Familial chylomicronemia syndrome in PortugalPublication . Alves, Ana Catarina; Miranda, Beatriz; Sequeira, Sílvia; Moldovan, Oana; Nunes, Catarina; Antunes, Henedina; Martins, Esmeralda; Gonçalves, Rute; Duarte, Sequeira; Guerra, António; Gaspar, Ana; Salgado, Miguel; Azevedo, Aida; Araújo, Francisco; Ferreira, Ana Cristina; Rato, Quitéria; Palma, Isabel; Bourbon, MafaldaFamilial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder of lipoprotein metabolism. It is characterized by marked elevation of triglyceride and chylomicron levels, lipaemic plasma, recurrent pancreatitis, eruptive xanthoma, hepatosplenomegaly, andliapemiaretinalis. All genes associated with FCS (LPL, APOC2, APOA5, LMF1 and GPHBP1) have an effect on the activity of lipoprotein lipase (LPL). The aim of this study is to present all cases with FCS clinical diagnosis, studied in our laboratory.
- Familial Chylomicronemia Syndrome: clinical and molecular characterization of individuals WITH clinical diagnosis in PortugalPublication . Alves, Ana Catarina; Abrantes, Leonor; Sequeira, Sílvia; Moldovan, Oana; Nunes, Catarina; Antunes, Henedina; Martins, Esmeralda; Gonçalves, Rute; Duarte, Sequeira; Guerra, António; Gaspar, Ana; Salgado, Miguel; Azevedo, Aida; Rato, Quitéria; Palma, Isabel; Bourbon, MafaldaAim: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder of lipoprotein metabolism. It is characterized by marked elevation of triglyceride and chylomicron levels, lipaemic plasma, recurrent pancreatitis, eruptive xanthoma, hepatosplenomegaly, and liapemia retinalis. All genes associated with FCS (LPL, APOC2, APOA5, LMF1 and GPHBP1) have an effect on the activity of lipoprotein lipase (LPL). The aim of this study is to present all cases with FCS clinical diagnosis, studied in our laboratory.
- Incidence of maple syrup urine disease in PortugalPublication . Quental, Sofia; Vilarinho, Laura; Martins, Esmeralda; Teles, Elisa Leão; Rodrigues, Esmeralda; Diogo, Luísa; Garcia, Paula; Eusébio, Filomena; Gaspar, Ana; Sequeira, Sílvia; Amorim, António; Prata, Maria JoãoMaple syrup urine disease is an autosomal recessive disorder of branched-chain amino acids metabolism with a worldwide frequency of 1/185,000 live newborns. In Portugal, the incidence of the disease has not been assessed. Based on the review of the cases diagnosed by tandem mass spectrometry an incidence of 1/86,800 live newborns was estimated in Portugal, indicating that the disease is more frequent in this country than reported in most populations.
- Next Generation Sequencing Improves Mitochondrial Diseases DiagnosisPublication . Nogueira, Célia; Vilarinho, Laura; Pereira, Cristina; Silva, Lisbeth; Vieira, Luis; Leão Teles, Elisa; Rodrigues, Esmeralda; Campos, Teresa; Janeiro, Patrícia; Costa, Claúdia; Gaspar, Ana; Soares, Gabriela; Bandeira, Anabela; Martins, Esmeralda; Magalhães, Marina; Sequeira, Sílvia; Vieira, José Pedro; Santos, HelenaObjectives: The overall aim of our research project was to develop a Next Generation Sequencing strategy to identify nuclear disease causing-mutations in patients suspicious of mitochondrial disorders but without molecular etiology.
- Rare primary dyslipidaemias associated with low LDL and HDL cholesterol values in PortugalPublication . Alves, Ana Catarina; Miranda, Beatriz; Moldovan, Oona; Espírito Santo, Raquel; Gouveia Silva, Raquel; Soares Cardoso, Sandra; Diogo, Luísa; Seidi, Mónica; Sequeira, Sílvia; Bourbon, MafaldaDyslipidaemia represents a group of disorders of lipid metabolism, characterized by either an increase or decrease in lipid particles, usually associated with triglycerides, LDL cholesterol (LDL-C) and/or HDL cholesterol (HDL-C). Most hyperlipidaemias and HDL deficiencies confer an increased cardiovascular risk, while hypolipidaemia, such as abeta or hypobetalipoproteinemia, may present different manifestations ranging from poor weight progression to neurological manifestations. The aim of this study is to present 7 cases with rare dyslipidaemias associated with low LDL or low HDL cholesterol values, referred to our laboratory for the genetic identification of the cause of the dyslipidaemia. Lipid profile was determined for each individual in an automated equipment Integra Cobas (Roche). Molecular analysis was performed by NGS with a target panel of 57 genes involved in lipid metabolism (Sure select QXT, Agilent) and samples were run in a NextSEQ Sequencer (Illumina). Only genes associated to rare forms of low HDL-c or LDL-c were analysed for this work, namely: ABCA1, APOA1, LCAT, SCARB1, APOB, PCSK9, MTTP, SAR1B, and ANGPTL3. All rare variants (MAF<5%) found in these genes were confirmed by Sanger sequencing. This study includes 7 index cases (IC), with the following clinical diagnoses: Fish Eye Disease (1), Hypoalphalipoproteinemia (1) and Abetalipoproteinemia (ABL) / Familial Hypobetalipoproteinemia (FHBL) (5). We have identified one IC with a compound heterozygosity in LCAT causing Fish Eye Disease and one IC with a variant in ABCA1 in homozygosity causing Tangier disease. We found variants causing homozygous FHBL in 2 IC, one of whom has an undescribed pathogenic variant in homozygosity in APOB (c.12087+1G>A) and the other is a possible compound heterozygous for APOB variants c.2604+1G>A and c.4651C>T/p.(Gln1551*). In two patients only a variant in heterozygosity (c.3365delG/p.(Gly1122Vfs*62) and c.11095A>T/p.(Arg3699*)). In the remaining patient, no variants were identified. NGS proved to be a fundamental key for genetic testing of rare lipid disorders, allowing us to find the genetic cause of disease in 6/7 patients with low HDL-c and LDL-c. Patients with these rare conditions should be identified as early as possible in order to minimize or prevent clinical manifestations. The unsolved case is still under investigation.