ABSTRACT
Background & objectives: There is no published literature on the extent of vitamin B12 deficiency in elderly Indians as determined by plasma vitamin B12 levels and methylmalonic acid (MMA) levels. Vitamin B12 deficiency is expected to be higher in elderly Indians due to vegetarianism, varied socio-economic strata and high prevalence of Helicobacter pylori infection. We therefore, studied the dietary habits of south Indian urban elderly population and measured vitamin B12, MMA red cell folate and homocysteine (Hcy) levels. Methods: Healthy elderly urban subjects (175, >60 yr) were recruited. Detailed history, physical examination and neurological assessment were carried out. Food Frequency Questionnaire (FFQ) for dietary analysis for daily intake of calories, vitamin B12, folate and detailed psychological assessment for cognitive functions was carried out. Blood samples were analyzed for routine haematology and biochemistry, vitamin B12, red cell folate, MMA and Hcy. Results: The mean age of the study population was 66.3 yr. Median values for daily dietary intake of vitamin B12 and folate were 2.4 and 349.2 μg/day respectively. Sixty two (35%) participants consumed multivitamin supplements. Plasma vitamin B12 level and the dietary intake of vitamin B12 was significantly correlated (P=0.157). Plasma vitamin B12 and Hcy were inversely correlated (P= -0.509). Red cell folate was inversely correlated with Hcy (P= -0.550). Significant negative correlation was observed between plasma vitamin B12 and MMA in the entire study population (P= -0.220). Subjects consuming vitamin supplements (n=62) had significantly higher plasma vitamin B12 levels, lower MMA levels and lower Hcy levels. There was no significant correlation between plasma vitamin B12, MMA, Hcy and red cell folate and any of the 10 cognitive tests including Hindi Mental Status Examination (HMSE). Interpretation & conclusions: Our study is indicative of higher vitamin B12 (2.4 μg/day) intakes in urban south Indian population. Thirty five per cent of the study population consumed multivitamin supplements and therefore, low plasma vitamin B12 levels were seen only in 16 per cent of the study subjects. However, MMA was elevated in 55 per cent and Hcy in 13 per cent of the subjects.
Subject(s)
Aged , Diet, Vegetarian , Erythrocytes/metabolism , Female , Folic Acid/blood , Helicobacter Infections/metabolism , Helicobacter pylori/isolation & purification , Homocysteine/blood , Humans , India/epidemiology , Male , Methylmalonic Acid/blood , Middle Aged , Vitamin B 12/administration & dosage , Vitamin B 12/blood , Vitamin B 12/metabolism , Vitamin B 12 Deficiency/blood , Vitamin B 12 Deficiency/epidemiology , Vitamin B 12 Deficiency/metabolismABSTRACT
CONTEXT AND OBJECTIVE: Polymorphisms in genes involved in folate metabolism may modulate the maternal risk of Down syndrome (DS). This study evaluated the influence of a 19-base pair (bp) deletion polymorphism in intron-1 of the dihydrofolate reductase (DHFR) gene on the maternal risk of DS, and investigated the association between this polymorphism and variations in the concentrations of serum folate and plasma homocysteine (Hcy) and plasma methylmalonic acid (MMA). DESIGN AND SETTING: Analytical cross-sectional study carried out at Faculdade de Medicina de São José do Rio Preto (Famerp). METHODS: 105 mothers of individuals with free trisomy of chromosome 21, and 184 control mothers were evaluated. Molecular analysis on the polymorphism was performed using the polymerase chain reaction (PCR) through differences in the sizes of fragments. Folate was quantified by means of chemiluminescence, and Hcy and MMA by means of liquid chromatography and sequential mass spectrometry. RESULTS: There was no difference between the groups in relation to allele and genotype frequencies (P = 0.44; P = 0.69, respectively). The folate, Hcy and MMA concentrations did not differ significantly between the groups, in relation to genotypes (P > 0.05). CONCLUSIONS: The 19-bp deletion polymorphism of DHFR gene was not a maternal risk factor for DS and was not related to variations in the concentrations of serum folate and plasma Hcy and MMA in the study population.
CONTEXTO E OBJETIVO: Polimorfismos em genes do metabolismo do folato podem modular o risco materno para síndrome de Down (SD). Este estudo avaliou a influência do polimorfismo de deleção de 19 pares de base (pb) no íntron 1 do gene dihidrofolato redutase (DHFR) no risco materno para SD e investigou a associação entre esse polimorfismo e variações nas concentrações de folato sérico, homocisteína (Hcy) e ácido metilmalônico (MMA) plasmáticos. TIPO DE ESTUDO E LOCAL: Estudo transversal analítico realizado na Faculdade de Medicina de São José do Rio Preto (Famerp). MÉTODOS: 105 mães de indivíduos com trissomia livre do cromossomo 21 e 184 mães controles foram avaliadas. A análise molecular do polimorfismo foi realizada pela reação em cadeia da polimerase (PCR) por diferença de tamanho dos fragmentos. O folato foi quantificado por quimioluminescência, e Hcy e MMA foram determinados por cromatografia líquida/espectrometria de massas sequencial. RESULTADOS: Não houve diferença entre os grupos em relação às frequências alélica e genotípica (P = 0,44; P = 0,69, respectivamente). As concentrações de folato, Hcy e MMA não mostraram diferença significativa entre os genótipos, entre grupos (P > 0,05). CONCLUSÕES: O polimorfismo de deleção de 19 pb do gene DHFR não é um fator de risco materno para SD e não está relacionado com variações nas concentrações de folato sérico, Hcy e MMA plasmáticos na população estudada.
Subject(s)
Adolescent , Child , Female , Humans , Down Syndrome/genetics , Folic Acid/metabolism , Polymorphism, Genetic/genetics , Tetrahydrofolate Dehydrogenase/genetics , Chi-Square Distribution , Cross-Sectional Studies , Gene Frequency , Homocysteine/blood , Methylmalonic Acid/blood , Polymerase Chain Reaction , Risk FactorsABSTRACT
La Acidemia Metilmalónica es un trastorno metabólico, caracterizado por un adecuado metabolismo de los aminoácidos esenciales. Las manifestaciones cutáneas en esta entidad son poco frecuentes en relación a otras aminoacidopatías. Presentamos la ocurrencia de lesiones cutáneas semejantes al Síndrome Estafilicocóccico de la Piel Escaldada en un neonato de 13 días de vida con diagnóstico de acidemia metilmalónica que fueron tratadas con antibióticos sin respuesta clínica, observándose la resolución de las mismas al ser compensado su cuadro metabólico
Subject(s)
Humans , Female , Infant, Newborn , Methylmalonic Acid/blood , Amino Acid Metabolism, Inborn Errors/diagnosis , Amino Acid Metabolism, Inborn Errors/diet therapy , Methylmalonyl-CoA Mutase , Staphylococcal Scalded Skin Syndrome/diagnosisABSTRACT
INTRODUÇAO: A vitamina B12 é hidrossolúvel, não-sintetizada pelo organismo humano, presente em alimentos de origem animal. Sua deficiência é muito freqüente entre idosos, vegetarianos e indivíduos que adotam baixa dieta protéica ou apresentam problemas de absorção gastrintestinal. FISIOPATOLOGIA: A deficiência de vitamina B12 leva a transtornos hematológicos, neurológicos e cardiovasculares, principalmente, por interferir no metabolismo da homocisteína (Hcy) e nas reações de metilação do organismo. Muitas vezes a deficiência pode permanecer assintomática por longos períodos, desencadeando uma deficiência crônica que, se mantida, pode levar a manifestações neurológicas irreversíveis. METODOLOGIAS: Metodologias eficientes que permitam um diagnóstico precoce são imprescindíveis. Porém um método considerado padrão-ouro ainda não é consensual. A dosagem sérica de vitamina B12 sofre algumas restrições pelos problemas de sensibilidade e especificidade, podendo ocorrer sintomas de deficiência mesmo com vitamina B12 sérica dentro dos níveis normais ou, de outro modo, ocorrendo baixos níveis de vitamina B12 sérica sem, contudo, apresentar baixos níveis da fração de vitamina realmente disponível para as células e sem apresentar sintomatologia. Novas alternativas vêm surgindo, como a dosagem de transcobalamina II (Tc II), a única fração de vitamina B12 disponível para as células, ou a dosagem de ácido metilmalônico (MMA) e Hcy, metabólitos que aumentam quando ocorre diminuição de vitamina B12 intracelular. Estes testes apresentam algumas vantagens, mas também limitações importantes para uso rotineiro. CONCLUSAO: Em casos subclínicos, um diagnóstico correto e precoce representa ainda um desafio, e futuros estudos são necessários para definir um método padrão para diagnóstico laboratorial da deficiência de vitamina B12.
Subject(s)
Humans , Methylmalonic Acid/blood , /diagnosis , /physiopathology , Homocysteine/blood , Sensitivity and Specificity , Transcobalamins/analysisABSTRACT
Neutropenia exists when the neutrophil counts is less than 1000/mm3 in infants between 2 weeks and 1 year of age and less than 1500/mm3 beyond 1 year of age (1). Severe infections occur when the absolute neutrophil count is below 500/mm3 with perirectal abscesses, pneumonia, and sepsis being common. Granulocyte Colony-Stimulating Factor (G-CSF) produces a sustained neutrophil recovery in patients with severe neutropenia, reduces the incidence and severity of infection, and improves the quality of life. Various cytopenias, including neutropenia, thrombocytopenia and pancytopenia, have been reported in association with inborn errors of branched aminoacid metabolism such as methylmalonic, propionic and isovaleric acidemia. We report an infant with methylmalonic acidemia who presented severe neutropenia
Subject(s)
Humans , Male , Infant, Newborn , Infant , Methylmalonic Acid/blood , Acidosis/complications , Amino Acid Metabolism, Inborn Errors/complications , Neutropenia/etiology , Acidosis/blood , Acidosis/therapy , Amino Acid Metabolism, Inborn Errors/blood , Amino Acid Metabolism, Inborn Errors/therapy , Granulocyte Colony-Stimulating Factor/therapeutic use , Infant, Premature , Neutropenia/blood , Treatment OutcomeABSTRACT
Methylmalonic acidemia is an inborn error of organic acid metabolism resulting from defects in methylmalonyl CoA mutase. Analysis of plasma free amino acids in a 15-month-old Thai infant by HPLC showed marked elevation of glycine. HPLC analysis of urinary organic acids showed high levels of methylmalonic acid.