Factores congénitos de los trastornos trombóticos arteriales en recién nacidos / Congenital factors of arterial thrombotic disorders in newborns

La trombosis arterial neonatal representa el 5,8% de todos los tipos de trombosis conocidos en recién nacidos, esto convierte a esta enfermedad en un punto de enfoque específico para su diagnóstico oportuno, y descifrar los factores congénitos de mayor recurrencia, se realizó una revisión sistemática PRISMA, donde se evaluaron 20 artículos de tipo observacional transversal, detallando los resultados obtenidos en cuanto al factor congénito más recurrente que en este caso es el sexo masculino, prematuridad y defectos genéticos se han mencionado además los marcadores bioquímicos y moleculares mayormente evaluados en esta muestra, demostrando que en estos casos los marcadores bioquímicos analizados con frecuencia son: antitrombina III, Proteína C y S, anticuerpos antifosfolípidos y homocisteína y como marcadores moleculares se evalúa con mayor recurrencia a: Factor V Leiden y el gen de la protrombina G20210A.

Factores congénitos de los trastornos trombóticos arteriales en recién nacidos / Congenital factors of arterial thrombotic disorders in newborns

La trombosis arterial neonatal representa el 5,8% de todos los tipos de trombosis conocidos en recién nacidos, esto convierte a esta enfermedad en un punto de enfoque específico para su diagnóstico oportuno, y descifrar los factores congénitos de mayor recurrencia, se realizó una revisión sistemática PRISMA, donde se evaluaron 20 artículos de tipo observacional transversal, detallando los resultados obtenidos en cuanto al factor congénito más recurrente que en este caso es el sexo masculino, prematuridad y defectos genéticos se han mencionado además los marcadores bioquímicos y moleculares mayormente evaluados en esta muestra, demostrando que en estos casos los marcadores bioquímicos analizados con frecuencia son: antitrombina III, Proteína C y S, anticuerpos antifosfolípidos y homocisteína y como marcadores moleculares se evalúa con mayor recurrencia a: Factor V Leiden y el gen de la protrombina G20210A.

Neonatal arterial thrombosis represents 5.8% of all known types of thrombosis in newborns, this makes this disease a specific point of focus for its timely diagnosis, and to decipher the congenital factors of greater recurrence, a systematic review PRISMA was performed, where 20 articles of cross-sectional observational type were evaluated, detailing the results obtained in terms of the most recurrent congenital factor which in this case is male sex, prematurity and genetic defects have also been mentioned biochemical and molecular markers mostly evaluated in this sample, showing that in these cases the biochemical markers frequently analyzed are: Antithrombin III, Protein C and S, antiphospholipid antibodies and homocysteine and as molecular markers are evaluated with greater recurrence to: Factor V Leiden and the prothrombin gene G20210A.

First Korean case of factor V Leiden mutation in pregnant woman with a history of recurrent pregnancy loss

Thrombophilia refers to inherited or acquired hemostatic disorders that result in a predisposition to blood clot formation. When combined with the hypercoagulable state that is characteristic of pregnancy, there is an increased risk of severe and recurrent pregnancy complications. Activated protein C resistance caused by factor V Leiden (FVL) mutation is known to be the most common cause of inherited thrombophilia in Caucasian population. FVL mutation has been related to pregnancy complications associated with hypercoagulation, e.g. miscarriage, intrauterine fetal demise, placental abruption, and intrauterine growth retardation. Although the FVL mutation is easily detected using molecular DNA techniques, patients who are heterozygous for this disorder often remain asymptomatic until they develop a concurrent prothrombotic condition. Because there are potentially serious effects of FVL mutation for pregnancy, and because effective treatment strategies exist, early detection and treatment of this condition might be considered.

Anti-phospholipid syndrome in seven leprosy patients with thrombotic events on corticosteroid and/or thalidomide regimen: insights on genetic and laboratory profiles

Abstract INTRODUCTION Corticosteroids and/or thalidomides have been associated with thromboembolism events (TBE) in multibacillary (MB) leprosy. This report aimed to determine genetic and laboratory profiles associated with leprosy and TBE. METHODS Antiphospholipid antibodies (aPL), coagulation-related exams, prothrombin and Leiden's factor V mutations, and ß2-glycoprotein-I (ß2GPI) Val247Leu polymorphism were assessed. RESULTS Six out of seven patients with leprosy were treated with prednisone and/or thalidomide during TBE and presented at least one positive aPL. All patients presented ß2GPI polymorphism, and one showed prothrombin mutation. CONCLUSIONS Corticosteroid or thalidomide adverse effects and aPL and ß2GPI polymorphisms may cause TBE in patients with MB leprosy.

Trombofilias hereditarias / Hereditary Thrombophilia

Las trombofilias hereditarias suponen un grupo de enfermedades que predisponen al desarrollo de enfermedad tromboembólica arterial y venosa, debido a déficit o ganancia de función de factores anticoagulantes o procoagulantes incrementando de manera significativa la morbilidad y mortalidad en la población adulta y pediátrica. La expresión y penetrancia genética de este grupo de enfermedades es diversa, y las formas de presentación clínica varía desde la purpura fulminans neonatal hasta episodios tromboembólicos recurrentes a edades tempranas y efectos adversos en el embarazo. El screening no es rutinario en pacientes con cuadros tromboembólicos y sus indicaciones son precisas, en especial personas menores a los 45 años, con cuadros recurrentes, y abortos o muertes fetales a repetición sin causa específica. El tratamiento es basado de acuerdo a la presentación del cuadro clínico, sin embargo la anticoagulación convencional es ampliamente utilizada en el manejo de este grupo de pacientes.

Inherited thrombophilia represent a group of diseases that predispose to the development of arterial and venous thromboembolic disease due to deficiency or gain of function of anticoagulant or procoagulant factors, increasing significantly the morbidity and mortality in the adult and pediatric population. Expression and genetic penetrance to this group of diseases is diverse, and the form of clinical presentation varies from the neonatal purple fulminans to recurrent thromboembolic events at a young age and pregnancy with side effects. The screening is not routine in patients with thromboembolic condition and its indications are accurate, especially in younger people than 45, with recurrent episodes of abortions or fetal deaths without specific cause. Treatment is based according to the clinical presentation of the condition; however conventional anticoagulation is widely used in the treatment of this patient group.

Comparison of the Real-Time PCR Tests for Factor V G1691A and Prothrombin G20210A with PCR-Restriction Fragment Length Polymorphism and Direct Sequencing Tests / 임상검사와정도관리

BACKGROUND: Factor V (FV) G1691A and prothrombin G20210A mutations are the most common targets of genetic tests for thromboembolism. This study compared the ability of real-time PCR to detect FV G1691A and prothrombin G20210A (BioSewoom, Korea) with that of PCR-restriction fragment length polymorphism (RFLP) and direct sequencing, to evaluate diagnostic equivalency. METHODS: Real-time PCR was compared with PCR-restriction fragment length polymorphism (RFLP) and direct sequencing using patients' samples as well as heterozygous and homozygous World Health Organization (WHO) reference reagent DNA. The limit of detection (LoD) for real-time PCR was determined using WHO reference reagents. RESULTS: All 141 and 156 patient samples were tested for the FV G1691A and prothrombin G20210A mutations, respectively; the results from all three methods (real-time PCR, PCR-RFLP, and direct sequencing) consistently showed that the samples were wild type. Each of the three methods showed the same results in tests using heterozygous and homozygous DNA from the WHO reference reagents. The LoD of wild type and homozygous samples was 65.16 pg/mL for FV G1691A, and 61.3 pg/mL for prothrombin G20210A. The LoD of heterozygous samples was 1,650.0 pg/mL for FV G1691A and 1,640.0 pg/mL for prothrombin G20210A. CONCLUSIONS: The real-time PCR test kits for FV G1691A and prothrombin G20210A showed reliable equivalency with PCR-RFLP and direct sequencing, and could be useful tests to detect gene polymorphisms for thromboembolism.

Inherited thrombophilia profile in patients with recurrent miscarriages: Experience from a tertiary care center in north India

The cause of recurrent miscarriage (RM) remains unexplained in approximately 30% to 50% cases. The association of inherited thrombotic factors and RM patients has not been documented from the northern part of India. A total of 40 patients had been investigated for inherited thrombophilia workup (protein C, protein S [PS], antithrombin III, and factor V Leiden [FVL] mutation) over a period of 10 years (2005 to 2014). RM patients were divided in to three groups. Group I (only 1st trimester loss), group II (only 2nd and 3rd trimester), and group III (mixed). Each group comprised of the following numbers of patients respectively: I, 24; II, 2; III, 14. Heterozygous FVL mutation was found in 10% (4/40) cases. PS deficiency was detected in 2.7% (1/37) cases. In the present study FVL and PS were seems to be associated with a subset of patients however further studies with larger numbers of patients are recommended for better evaluation.

Síndrome de Budd Chiari: Reporte de tres casos y revisión de la literatura / Budd Chiari Syndrome: Three Case Reports and a Literature Review

Se describen los casos de tres pacientes de sexo femenino a quienes se les hizo diagnóstico de síndrome de Budd Chiari. En una paciente la presentación del síndrome fue subaguda, pudiendo ser manejada exitosamente con la colocación de TIPS. Otra con mutación del factor V Leyden asociada desarrolló disfunción hepática progresiva y requirió de trasplante hepático. En dos de los tres casos se identificó una enfermedad hematológica como trastorno de base, y en uno el uso de anticonceptivos orales como factor de riesgo. Las tres pacientes fueron sometidas a terapia anticoagulante y el manejo quirúrgico fue definido de acuerdo a su condición clínica. Sin embargo, en un caso la presentación fue aguda con falla hepática y muerte.

This article describes the cases of three female patients who were diagnosed with Budd-Chiari syndrome. One patient was subacute and could be successfully managed by placement of a transjugular intrahepatic portosystemic stent (TIPS). Another patient who had the Factor V Leiden mutation developed associated progressive liver dysfunction and required liver transplantation. A hematologic disease was identified as the underlying disorder in two of the three cases. For one patient, the use of oral contraceptives was a risk factor. Since all three patients were undergoing anticoagulant therapy, surgical management was determined according to each patient’s clinical condition. Nevertheless, the one patient who that presented acute hepatic failure did not survive.

Prevalence of thromogenic gene mutations in women with recurrent miscarriage: A retrospective study of 1,507 patients

OBJECTIVE: Thromogenic gene mutations has been thought to be associated with recurrent pregnancy loss in women in Turkey. The aim of this study was to investigate the prevalence of thromogenic gene mutations such as factor V Leiden (FVL, G1691T), prothrombin (G20210A), and the methylene tetrahydrofolate reductase (MTHFR, C677T) mutation in women with recurrent pregnancy loss. METHODS: This descriptive study was carried out in the Department of Obstetrics and Gynaecology, Harran University School of Medicine, and included a total of 1,507 women with histories of recurrent pregnancy loss between January 2010 and June 2013. The mutations were assessed by using the polymerase chain reaction. RESULTS: The homozygous mutation frequencies of FVL, prothrombin, and MTHFR were found to be 3 (0.20%), 0 and 125 (8.29%), and the heterozygous mutation frequencies were 83 (5.51%), 61 (4.05%), and 612 (40.61%), respectively. Among the 86 FVL mutation patients, 38 also had accompanying prothrombin and MTHFR mutations. CONCLUSION: Since the homozygous forms of the FVL-prothrombin gene mutations have low incidences and MTHFR mutation is similar to a healthy population, preconceptional thromogenic gene mutations screening seems to be controversial.

Analysis of factor V Leiden and prothrombin mutations in patients with suspected thrombophilia in São Paulo state-Brazil / Análise da mutação no fator V de Leiden e na protrombina em pacientes do estado de São Paulo, Brasil

INTRODUCTION: Prothrombin (factor II) is a thrombin precursor, which induces fibrin formation. A mutation in the prothrombin gene (G20210A) has been described, which is directly associated with high prothrombin levels, hence thrombophilia. G1691A mutation in the factor V Leiden (FVL) gene occurs on exon 10, one of the main cleavage sites for protein C activation, resulting in protein alteration. OBJECTIVE: To identify and estimate the genotype frequency of the three possible genotypes and the frequency of the two existing alleles in the FVL and prothrombin genes in patients with suspected thrombophilia in the state of Sao Paulo. This study may provide more literature and reference data on the incidence of prothrombin genotypes among individuals in Brazil. MATERIAL AND METHODS: Analysis of point mutation by real time polymerase chain reaction (RT-PCR). RESULTS: We obtained a total of 100 individuals, from which 94% had the homozygous G genotype. Only 6% had heterozygous genotype and there was no individual with the homozygous genotype A for FVL gene. As to the prothrombin gene, the frequency was 97% for homozygous G genotype and 3% for the heterozygous genotype. There was no patient with the homozygous A genotype. CONCLUSION: This study demonstrated that the genotype identification of these genes is advisable for patients with suspected thrombophilia in this region.

INTRODUÇÃO: A protrombina (fator II) é a precursora da trombina, que induz a formação de fibrina. Foi descrita uma mutação no gene da protrombina (G20210A), associado diretamente a altos níveis de protrombina no sangue e, consequentemente, a trombofilia. A mutação G1691A no gene do fator V de Leiden (FLV) localiza-se no éxon 10, resultando na alteração da proteína, um dos principais sítios de clivagem para ativação da proteína C. OBJETIVOS: Identificar e estimar a frequência genotípica dos três possíveis genótipos, assim como estimar a frequência dos dois alelos existentes no gene do FLV e na protrombina em pacientes com suspeita de trombofilia no estado de São Paulo. Este estudo poderá fornecer mais dados para a literatura e para consulta da incidência dos genótipos da protrombina em indivíduos no Brasil. MATERIAL E MÉTODOS: Análise de mutação pontual por reação em cadeia da polimerase em tempo real (RT-PCR). RESULTADO: Obtivemos o número de 100 indivíduos e, desse total, 94% possuíam o genótipo para homozigoto G; apenas 6%, genótipo heterozigoto; nenhum indivíduo foi encontrado com genótipo homozigoto A no gene do FLV. No gene da protrombina, a frequência foi de 97% para o genótipo homozigoto G e 3% para o genoma heterozigoto; não foi encontrado nenhum indivíduo com o genoma homozigoto A. CONCLUSÃO: Este estudo mostrou que é recomendável a identificação do genótipo para esses genes em pacientes com suspeita de trombofilia nessa região.

Alterações genéticas em casais com antecedentes de aborto recorrente no primeiro trimestre da gestação / Genetic alterations in couples with a history of recurrent miscarriage in the first trimester of pregnancy

O abortamento é considerado um problema multifatorial, cujas principais causas envolvidas na sua etiologia são os fatores ambientais (como exposição a substâncias tóxicas), genéticos, anatômicos, endócrinos, imunológicos, trombofílicos e doenças infecciosas (como toxoplasmose, rubéola). No entanto, os fatores genéticos são atribuídos principalmente aos abortamentos de primeiro trimestre da gestação. As alterações cromossômicas, o polimorfismo C677T, no gene da metilenotetrahidrofolato redutase (MTHFR677C>T); o polimorfismo G1691A, no gene do Fator V de Leiden (FVL1691G>A), e o polimorfismo G20210A, no gene da protrombina (PRT20210G>A), têm sido associados a problemas obstétricos, incluindo aborto recorrente. O objetivo deste trabalho foi investigar associação entre as mutações relacionadas à trombofilia, presença de alterações cromossômican e a ocorrência de aborto espontâneo recorrente e avaliar possíveis interações entre as referidas mutações e as alterações cromossômicas. A casuística foi composta por 151 mulheres com história de aborto recorrente, 94 parceiros e 100 controles (mulheres sem histórico de aborto). A investigação das mutações foi realizada pela técnica de Reação em Cadeia da Polimerase- Polimorfismo de Tamanho de Fragmento de Restrição. As alterações cromossômicas foram investigadas pela cariotipagem com banda–G. A frequência das alterações cromossômicas foi de 7,3% nas mulheres com abortamento recorrente e 1% nos controles (p=0,022), e de 2,1% nos parceiros. No entanto, a frequência dos alelos MTHR677C>T (23% versus 22,5%), FVL1691G>A (1,5% versus 1% ) e PRT20210G>A (1,45% versus 0%) foi similar entre casos e controles, respectivamente. No grupo investigado, foi observada associação entre aborto recorrente e alterações cromossômicas, mas não foi encontrada associação com os polimorfismos gênicos investigados.

Abortion is considered a multifactorial problem, the most important causes involved in its etiology are, environmental factors ( as exposure to toxic chemicals), genetic, anatomic, endocrine, immunological, thrombophilic and infectious diseases (such as toxoplasmosis, rubella). However, genetic factors are mainly attributed to abortions of the first trimester of pregnancy. Chromosomal abnormalities, MTHFR 677C>T, factor V Leiden 1691G>A and prothrombin 20210G>A mutations have been associated with obstetric problems, including recurrent miscarriage. The objective of this research was to investigate associations between mutations in three genes commonly associated to thrombophilic events, chromosomal abnormalities and the occurrence of recurrent miscarriage. As well evaluate possible interactions between these mutations and chromosomal abnormalities. The sample was comprised of 151 women with history of recurrent miscarriages, 94 partners and 100 control (women with no history of abortion). The investigation of the mutations was performed by Polymerase Chain Reaction (PCR)/ Restriction Fragment Length Polymorphism (RFLP). Chromosomal aberrations were investigated by karyotyping with G-banda. The frequency of chromosomal abnormalities was 7.3% in women with recurrent miscarriage and 1% in controls (p = 0.022), and 2.1% in the partners. However, the frequency of allele MTHR677C> T (23% versus 22.5%), FVL1691G> A (1.5% vs. 1%) and PRT20210G> A (1.45% vs. 0%) was similar for cases and controls, respectively. In the investigated group was found association between recurrent miscarriage and chromosomal abnormalities, but no association was found with the genetic polymorphisms investigated.

Mutação do fator V de Leiden em paciente com síndrome de Down: relato de caso / Mutation in factor V Leiden in patients with Down syndrome: case report

JUSTIFICATIVA E OBJETIVOS: A mutação no fator V de Leiden é a anormalidade genética predisponente mais comum para tromboembolismo venoso (TEV). Sua forma heterozigótica é encontrada em 5% da população e a forma homozigótica em 1% da população. A alta prevalência da doença de Leiden na população em geral correlacionada com níveis relativamente baixos de TEV sugere que a mutação produz um risco moderadamente aumentado de trombose, e que existe combinação com outros fatores de risco, dentre eles, o uso de anticoncepcional oral (ACO). Pouco se conhece sobre o risco de TEV em pacientes com síndrome de Down (SD). O objetivo deste estudo foi relatar o caso de paciente portadora de SD, fazendo uso de ACO, que apresentou acidente vascular encefálico isquêmico (AVEi) e trombose venosa profunda (TVP), bem como realizar uma revisão bibliográfica sobre os eventos tromboembólicos acometendo os portadores de SD. RELATO DO CASO: Paciente do sexo feminino, 17 anos, portadora de SD, em tratamento com levotiroxina sódica, obesa, após um ano do início de ACO apresentou quadro compatível com AVEi, e dois dias após, TVP de membro inferior esquerdo,sendo diagnosticada com mutação do fator V de Leiden. CONCLUSÃO: Devido à maior incidência de obesidade, sedentarismo e hipotireoidismo nos pacientes com SD, pode-se considerar que o uso de ACO venha a ser um fator adicional para a ocorrência de eventos tromboembólicos nestes pacientes. No entanto, até o momento não há dados que apontem maior prevalência de mutação do fator V de Leiden nos portadores de SD. Propõem-se novos estudos clínicos para avaliar os distúrbios da hemostasia nos pacientes com SD.

BACKGROUND AND OBJECTIVES: The most common clotting abnormality associated with venous thromboembolism is a reduced inactivation of coagulation factor V. This abnormality has a prevalence of 1% to 7% in the general population and 20% to 30% of patients with thrombosis. The high prevalence of the mutation in factor V in the general population, correlated with relatively low levels of venous thromboembolism suggests that the mutation produces a moderately increased risk of thrombosis, and there is a combination with other risk factors such as the use of oral contraceptives (OCA). The risk of venous thromboembolism (VTE) in patients with Down syndrome (DS) isn't well known, and the benefit on using OCA in this population it is questionable. The objective is describing the case of a patient with DS who had an ischemic stroke and deep vein thrombosis. CASE REPORT: Female patient, 17 years-old, with DS, 17 years old, treated with levothyroxine, obese, one year after the start of OCA presented clinically compatible with ischemic stroke, and two days later, deep vein thrombosis in left lower limb. After laboratory tests, was diagnosed with mutation of factor V Leiden. CONCLUSION: Due to a higher incidence of obesity, sedentary lifestyle and hypothyroidism in patients with DS, we can consider that the use of OCA will be an additional factor for the occurrence of thromboembolic events in these patients. We propose the evaluation of coagulation tests and research for congenital disorders of hemostasis in patients with DS before the beginning of OCA use.

Pharmacogenetic typing for oral anti-coagulant response among factor V Leiden mutation carriers.

Context: Factor V Leiden mutation is the most common inherited predisposition for hypercoagulability and thereby a common genetic cause for initiation of oral anti-coagulation therapy. There is a dearth of knowledge of coumarin response profile in such thrombophilic population. Aims: The current pilot study aims to estimate coumarin sensitivity in an Indian cohort with an inherited thrombophilia risk factor (Factor V Leiden mutation carriers) based on the observed frequency of CYP2C9 *2, *3 and VKORC1-1639G >A genotype combinations. Settings and Design: A retrospective study carried out in a tertiary health care center in India. Materials and Methods: Carriers of FVL mutation were genotyped for CYP2C9 (*2, *3) and VKORC1 (-1639G >A) variants by PCR-RFLP technique. Statistical Analysis Used: Chi-square test to analyze difference in expected and observed genotype frequency. Results: Sixty-one (n = 61) unrelated carriers of FVL mutation were observed in the 13 years study period. The allele frequency of CYP2C9 *2, CYP2C9 *3, and VKORC1-1639A in this cohort was 0.06, 0.11, and 0.16, respectively. Six (9.7%) individuals had two of the three variant alleles (heterozygous or homozygous), and 28 (45.9%) were heterozygous for at least one polymorphism. Conclusions: Pre-prescription genotyping for coumarin drugs, if introduced in Indians with inherited thrombophilia (in whom oral anti-coagulant therapy may be necessary), is likely to identify 9.7% (hypersensitive) subjects in whom the optimum anti-coagulation may be achieved with reduced dosages, 44.3% (normal sensitivity) who may require higher dose and also 55.6% (hyper and moderate sensitivity) subjects who are likely to experience bleeding episodes.

Thrombophilic molecular markers in young patients (<40 years) with coronary artery disease.

Background: There has been an alarming rise in the incidence of coronary artery disease (CAD) in India especially involving the age group of less than 45 years. In recent past, various studies focused on hemostatic aspects of CAD, but could not determine the significance of thrombophilic molecular marker in combination. The study was undertaken to investigate the association of thrombophilia related molecular markers in young patients with CAD. Materials and Methods: Thirty diagnosed patients with CAD of either sex under 40 years were included. Thirty healthy age and sex matched control subjects without evidence of CAD formed the control group. Detailed history and clinical examination findings were recorded. In addition to routine investigations, polymerase chain reaction (PCR) based molecular analysis for Factor V Leiden (FVL), methyltetrahydrofolate reductase (MTHFR) gene, tumor necrosis factor receptor 2 (TNFR2) gene, and prothrombin gene mutation were carried out. Results: The mean age (± SD) was 36.86 ± 3.90 years in the patients. Smoking was the most prevalent risk factor. FVL, MTHFR and TNFR2 gene mutation were seen in nine (30%) patient. Three patients had presence of more than one mutation. FVL, MTHFR and TNFR2 gene mutation was found in 4 (13.3%), 3 (10%), and 5 (16.6%) patients respectively. Prothrombin gene mutation was not seen in any of the subjects. There was no significant difference in lipid profile, fibrinogen levels and CRP among the patients with mutation and patients without mutation. Conclusion: Almost one-third of the cases were positive for the various mutations in the study and the presence of at-least one or the other risk factor adds on to the risk of future thrombosis. There is a need to demonstrate or document these mutations in a larger group further based upon ethnicity and geographic distribution.

Large-scale meta-analysis of genetic studies in ischemic stroke: Five genes involving 152,797 individuals.

BACKGROUND: Ischemic stroke descent has a genetic basis. Stroke represents a complex trait, which is assumed to be polygenic. On this topic, the role of a wide number of candidate genes has been investigated in stroke through association studies. MATERIALS AND METHODS: We performed a literature-based systematic review of genetic association studies in stroke abound several populations. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined for each gene-disease association. Following a review of 300 manuscripts, five candidate gene variants were analyzed among 152,797 individuals (45,433 cases and 107,364 controls). RESULTS: For these five candidate genes studied, the prothrombin OR is 1,57 (1,23-2,89), the factor V Leiden OR is 1,43 (0,67-6,24), the mean OR of angiotensin I converting enzyme (ACE) insertion/deletion (I/D) polymorphism is 1,11 (1,02-1,25), the summary OR for the C677T variant of 5,10-methylenetetrahydrofolate reductase (MTHFR) is 1,23 (0,61-1,47) and the pooled OR for the apolipoprotein E (APOE) gene is 0,95 (0,77-1,14) . CONCLUSION: These data suggest the genetic associations of some genes with ischemic stroke and it is necessary to compete with other genes. Our findings could represent an epidemiological base and a useful tool to address further molecular investigations and to realize more detailed meta-analyses.

Asociación de la RPCA con mutaciones Leiden y Cambridge del factor V de la coagulación en pacientes mexicanos con trombofilia primaria / Association of resistance to activated protein with the presence of Leiden and Cambridge Factor V mutations in Mexican patients with primary thrombophilia

Introducción: Las mutaciones Leiden y Cambridge del factor V de la coagulación y la resistencia a la proteína C activada (RPCA) son alteraciones que se relacionan con trombosis venosa y arterial. En este trabajo se analizó si la RPCA está asociada con las mutaciones Leiden y Cambridge, y la frecuencia de éstas en población mestiza mexicana. Material y métodos: Se incluyeron 150 pacientes mexicanos con trombofilia primaria y 100 sujetos sanos. Se determinó la RPCA empleando método comercial y los genotipos factor V Leiden y factor V Cambridge mediante PCR-RFLPs. Resultados: La RPCA fue positiva en cuatro pacientes y en un individuo control; sin embargo, no se encontró la mutación Leiden o Cambridge en la población estudiada, por lo que la RPCA no se correlacionó con ninguna de las mutaciones investigadas. Conclusiones: Los resultados indican que existen otras causas primarias o secundarias diferentes a las analizadas, que condicionan la RPCA. Además, la frecuencia obtenida para la RPCA en nuestra población trombofílica mestiza mexicana fue menor comparada con la obtenida en población caucásica, quizá por tratarse de poblaciones genéticamente diferentes.

BACKGROUND: Leiden and Cambridge factor V coagulation mutations and activated protein C resistance (RaPC) are alterations related with vein and artery thrombosis. In this study we aimed to determine whether RaPC is associated with the presence of Leiden and Cambridge mutation and the frequency of these mutations in the racially mestizo Mexican population. METHODS: We included 150 Mexican patients with primary thrombophilia and 100 healthy subjects in this study. RaPC was determined using commercial methods and genotypes FV Leiden and FV Cambridge with PCR-RFLPs. RESULTS: RaPC was positive in four patients and in one control individual; however, there was no presence of Leiden or Cambridge mutation in the studied group; thus, RaPC was not correlated with the presence of any of the studied mutations. CONCLUSIONS: These results indicate that there are other primary or secondary causes different from those studied, which condition the presence of RaPC. Furthermore, the frequency obtained for RaPC in our thrombophilic population of racially mixed Mexicans is lower compared to that obtained in the Caucasian population, most probably because they are genetically different populations.

The frequency of β-globin gene haplotypes, α-thalassemia and genetic polymorphisms of methylenetetrahydrofolate reductase, factor V Leiden and prothrombin genes in children with sickle cell disease in Rio de Janeiro, Brazil: [letter to editor] / Frequência dos haplótipos da globina beta, da talassemia alfa e dos polimorfismos genéticos dos genes da metilenotetrahidrofolato redutase, do fator V Leiden e da protrombina em crianças com doença falciforme no Rio de Janeiro, Brasil: [carta ao editor]

A freqüência dos haplótipos beta S e beta C do gene da globina e a prevalência de talassemia alfa e de mutações nos genes da metilenotetrahidrofolato redutase (MTHFR-C677T), do fator V de Leiden e da protrombina (G20210A) foi estudada em crianças com doença falciforme do Rio de Janeiro. O haplótipo Bantu foi o mais freqüente (65,9 por cento), 21,2 por cento das crianças (18 por cento heterozigotas e 3 por cento homozigotas) apresentam talassemia com mutação alfa 3.7kb, ao contrário da mutação alfa 4.2kb que não foi encontrada. Os alelos 677CT e 677TT da MTHFR foram observados em 20,2 por cento e 4,8 por cento, respectivamente. Os haplótipos Camarões, Árabe-Indiano e Senegal não foram detectados na amostra estudada, bem como mutações no gene do fator V de Leiden e da protrombina. Somente o haplótipo beta C CI foi observado. Esse é o primeiro estudo realizado em uma amostra proveniente do Programa de Triagem Neonatal para Hemoglobinopatias do estado do Rio de Janeiro. Apesar do Rio de Janeiro ser a segunda maior cidade brasileira e seus habitantes expressarem o elevado grau de miscigenação ocorrida no país, nossos resultados ainda coincidem com os registros históricos dos fluxos migratórios do gene beta S para o Brasil, bem como refletem a forte influência de indivíduos de origem africana na população do Rio de Janeiro.

Mutação G20210A no gene da protrombina, fator V de Leiden e anticorpos anticardiolipina não influenciam a sobrevida do enxerto renal após o transplante / Prothrombin G20210A gene mutation, factor V Leiden and anticardiolipin antibodies do not influence renal graft survival after transplantation

Introdução: Complicações tromboembólicas são importantes fatores de risco para perda do enxerto e pior evolução após o transplante renal. pacientes com defeito trombofílico apresentam maior risco de complicações tromboembólicas. Foram analisados, entre receptores de transplante renal, a prevalência de defeito trombofílico e o risco atribuído a esta condição para a perda do enxerto e para o desenvolvimento de tromboses intravasculares. Métodos: estudo do tipo coorte incluindo 388 receptores adultos analisados quanto à presença de trombofilia de acordo com a pesquisa de anticorpos anticardiolipidina (aCL) por ELISA e das mutações G1691A no gene do fator V (FV) e G20210A no gene da protrombina (PT) por PCR multiplex. Resultados: Defeito trombofílico foi identificado em 25,8% dos pacientes. As taxas de sobrevida de 2 anos do enxerto foram semelhantes entre os pacientes com e sem defeito trombofílico (94%, p=0,53), bem como a sobrevida dos enxertos livres de tromboses intravasculares (97% versus 97%, p=0,83). pacientes com defeito trombofílico apresentaram prevalência de tromboses intravasculares semelhante à do grupo-controle (3% versus 3,5%, p=0,82). O transplante renal anterior foi associado a maior risco de perda de enxerto (OR 20,8, p<0,001) e de ocorrência de trombose intravasculares (OR 6,8, p=0,008). Conclusões: As prevalências das mutações FVG1691A e PTG20210A na população estudada foram semelhantes às da população geral não transplantada, e a prevalência de anticorpos aCL superou a observada entre os indivíduos sadios. Não houve associação entre os marcadores de trombofilia estudados e a sobrevida em médio prazo do transplante renal.

Introduction: Thromboembolic complications are important risk factors for graft loss and poor outcome after renal transplantation. patients with thrombophilic defects are at increased risk of thromboembolic complications. Were analyzed, among kidney transplant recipients, the prevalence of thrombophilic defects and the risk attributed to this condition for graft loss and the development of intravascular thrombosis. Methods: A cohort study including 388 adult recipients analyzed for the presence of thrombophilia according to anticardiolipidina antibodies (aCL) by ELISA and gene mutations G1691A in factor V (FV) and prothrombin gene G20210A (PT) by multiplex PCR. Results: thrombophilic defect was identified in 25.8% of patients. The survival rates of two years of the graft were similar between patients with and without thrombophilic defect (94%, p = 0.53), and the survival of free grafts of intravascular thrombosis (97% versus 97%, p = 0 , 83). patients with an increased prevalence of thrombophilic defect intravascular thrombosis similar to the control group (3% versus 3.5%, p = 0.82). Previous renal transplantation was associated with increased risk of graft loss (OR 20.8, p <0.001) and intravascular thrombosis (OR 6.8, p = 0.008). Conclusions: The prevalence of mutations and FVG1691A PTG20210A in this study were similar to those of the general population not transplanted, and the prevalence of aCL antibodies exceeded that observed among healthy individuals. There was no association between markers of thrombophilia studied and medium-term survival in renal transplantation.

Trombose venosa em criança / Venous thrombosis in children

A incidência de trombose venosa profunda (TVP) em crianças (0 a 18 anos) é baixa. O objetivo desse trabalho é estudar uma criança de 12 anos que, após um trauma, apresentou TVP. Atividades de proteína C, proteína S, antitrombina e resistência à proteína C ativada (RPCA) foram analisadas em coagulômetro. O fator V de Leiden (FVL) foi pesquisado. O paciente e seu pai (assintomático até o momento) foram heterozigotos para FVL e sua mãe foi homozigota normal. Concluímos que o FVL associado a outras condições clínicas tende a ser multiplicativo para a ocorrência de trombose, que é multifatorial.

The incidence of deep venous thrombosis (DVT) in children (0-18 years old) is low. The aim of this study was to investigate the case of a 12 year-old child that had DVT after a trauma. Protein C and protein S activities, antithrombin and resistance to activated protein C were analyzed in coagulometer. Factor V Leiden (FVL) was studied. The patient and his father were heterozygotes for FVL. His mother was normal homozygote. We concluded that the presence of FVL associated with other medical conditions tends to multiply the occurrence of thrombosis, which is a multifactorial disease.

Coexistencia de las mutaciones C677T y A1298C en la enzima 5,10 metilentetrahidrofolato reductasa en pacientes pediátricos con trombosis / Coexistence of C677T and A1298C mutations in the 5,10 methylenetetrahydrofolate reductase enzyme in pediatric patients with thrombosis

Introducción. Una de las alteraciones genéticas que predisponen a trombosis, y que ha sido ampliamente estudiada, es la mutación C677T en el gen que codifica para la enzima 5,10 metilentetrahidrofolato reductasa (MTHFR). Así también, la presencia de la mutación A1298C en el mismo gen es considerada como un factor genético que predispone a trombosis. Métodos. Estudio realizado a 9 pacientes pediátricos con diagnóstico de trombofilia, 7 de sexo masculino y 2 del femenino, con edades de 1 mes a 13 años, a los cuales se les realizó, mediante la reacción en cadena de la polimerasa en tiempo real, el estudio de las mutaciones C677T y A1298C en la enzima MTHFR, la mutación G1691A (Leiden) del factor V y la mutación G20210A de la protrombina. Por métodos convencionales se realizó el fenómeno de resistencia a la proteína C activada (RPCa) y las proteínas C y S de la coagulación, así como la antitrombina (AT). Resultados. Todos los pacientes presentaron la coexistencia de las mutaciones C677T y A1298C en la MTHFR; solamente uno de ellos presentó un estado homocigoto para C677T y heterocigoto para A1298C, los otros 8 pacientes presentaron estados heterocigotos para ambas mutaciones; en los 9 pacientes no se demostró la presencia de las mutaciones G1691A del factor V (Leiden) y la G20210A de la protrombina, ni alteraciones en la RPCa, AT y las proteínas C y S de la coagulación. Conclusiones. La coexistencia de las mutaciones C677T y A1298C debe considerarse para su investigación en todos los pacientes que presenten un estado de trombofilia.

Introduction. One of the thrombophilic conditions that has been widely studied is the C677T mutation in the gene encoding the 5,10 methylenetetrahydrofolate reductase (MTHFR) enzyme. The presence of mutation A1298C in the same gene is also considered as one factor that predisposes thrombosis. Methods. We report on 9 pediatric patients diagnosed with thrombophilia, 7 males and 2 females with ages ranging from 1 month to 13 years. Real-time polymerase chain reaction was performed along with the study of the C677T and A1298C mutations in the MTHFR enzyme, G1691A mutation (Leiden) and factor V, prothrombin mutation G20210A. Conventional methods were used for activated protein C (APC) resistance and protein C and S coagulation, as well as antithrombin (AT). Results. All patients had coexisting mutations C677T and A1298C in MTHFR. Only 1 patient was homozygous for C6 7 7T and heterozygous for A1298C. The other 8 patients presented heterozygous mutations and in the 9 patients the presence of mutations of G 1691A factor V (Leiden) and G20210A prothrombin was not demonstrated, as well as alterations in APC, AT and proteins C and S. Conclusions. Coexistence of the C677T and A1298C mutations should be considered for investigation in all patients presenting thrombophilia.