As trombofilias na perda gestacional de repetição: uma revisão de prevalência e condutas / Thrombophilias in recurrent pregnancy loss: a review of prevalence and conduct

Objetivo: Discutir o papel das trombofilias na perda gestacional de repetição, com foco em prevalência/associação dessas patologias com perdas de repetição e seu tratamento, por meio de resultados de ensaios clínicos, revisões sistemáticas e metanálises. Métodos: Trata-se de uma revisão não sistemática de artigos publi- cados nas bases eletrônicas PubMed, Cochrane e SciELO nos últimos cinco anos, utilizando os seguintes descritores: "recurrent pregnancy loss", "recurrent abortion", "habitual abortion", "thrombophilia", "antiphospholipid syndrome" e "treatment". Resultados: A maioria dos estudos relatou forte associação entre os anticorpos antifosfolípides específicos e a síndrome do anticorpo antifosfolípide com perda gestacional de repetição. Mulheres portadoras da mutação do fator V de Leiden, mutação do gene da protrombina e deficiência de proteína S apresentaram alto risco de perda gestacional de repetição em uma grande revisão sistemática. Estudos recentes demonstraram taxas de prevalência das trombofilias hereditárias e da síndrome do anticorpo antifosfolípide, em mulheres com perda gestacional de repetição, semelhantes às da população em geral. Os estudos atuais endossam o uso da heparina associada à aspirina em mulheres com síndrome do anticorpo antifosfolípide, com aumento da taxa de nascidos vivos, mas sem diferença em re- lação às complicações obstétricas. Conclusão: Apesar de novos estudos demons- trarem que a prevalência das trombofilias hereditárias e adquiridas em mulheres com perda gestacional de repetição é semelhante à da população em geral, reco- menda-se a pesquisa rotineira de síndrome do anticorpo antifosfolípide nessas pacientes. O uso de aspirina em baixas doses associada à heparina é a intervenção farmacológica de primeira linha para a prevenção de perda gestacional de repeti- ção em pacientes com síndrome do anticorpo antifosfolípide.

Objective: To discuss the role of thrombophilias in recurrent pregnancy loss, focu- sing on the prevalence/association of these pathologies with recurrent abortion and treatment, through results of clinical trials, systematic reviews and meta-analyses. Methods: This is a non-systematic review of articles published in electronic databa- ses PubMed, Cochrane, SciELO in the last five years, using the following descriptors: "recurrent pregnancy loss", "recurrent abortion", "habitual abortion", "thrombophilia", "antiphospholipid syndrome", and "treatment". Results: Most studies have reported a strong association between specific antiphospholipid antibodies and antiphospho- lipid antibody syndrome with recurrent pregnancy loss. Women carrying the factor V Leiden mutation, prothrombin gene mutation, and protein S deficiency were shown to be at high risk of recurrent pregnancy loss in a large systematic review. Recent studies have shown prevalence rates of hereditary thrombophilias and antiphospholipid antibody syndrome, in women with re- current pregnancy loss, similar to those of the general po- pulation. Current studies endorse the use of heparin plus aspirin in women with antiphospholipid antibody syndrome, with an increase in live birth rate, but with no difference in obstetric complications. Conclusion: Although new studies demonstrate that the prevalence of hereditary and acquired thrombophilias in women with recurrent pregnancy loss is si- milar to that of the general population, routine investigation of antiphospholipid antibody syndrome in these patients is recommended. The use of low-dose aspirin plus heparin is the first-line pharmacological intervention for the prevention of recurrent pregnancy loss in patients with antiphospholipid antibody syndrome.

Prevalence of thrombophilia-associated genetic risk factors in blood donors of a regional hospital in southern Brazil

ABSTRACT Introduction: Thromboembolic events occur due to an imbalance in the hemostasis and some factors associated with this condition can be inherited. In order to evaluate the frequency of genotypes considered to be common hereditary risk factors for thrombophilia associated with venous thrombosis (g.1691G>A and g.20210G>A) and hyperhomocysteinemia (g.677C>T and g.1298A>C), samples from voluntary healthy blood donors at the Hospital de Clínicas de Porto Alegre were tested. Methods: We examined 325 blood samples from blood donors collected from October 2017 to July 2018. Blood was collected on filter paper and the DNA was extracted for single nucleotide polymorphisms (SNPs) analysis using the qualitative real time polymerase chain reaction. Results: The calculated frequencies of each genetic variant in heterozygosity were 4% for the FV gene (g.1691G> A), 4% for the F2 gene (g.20210G> A) and 42% and 39% for methylenetetrahydrofolate reductase (MTHFR), g.677C>T and g.1298A>C, respectively. Only the genetic variants of MTHFR were found in homozygosity, with frequencies of 14% and 6% (g.677C>T and g.1298A>C), respectively. Discussion: Altogether, these results describe the frequencies of genetic variants associated with venous thrombosis and hyperhomocysteinemia in the analyzed group and are important to enhance our current knowledge about the genetic profiles of Brazilian blood donors.

Lipase and factor V (but not viral load) are prognostic factors for the evolution of severe yellow fever cases

BACKGROUND Despite a highly efficacious vaccine, yellow fever (YF) is still a major threat in developing countries and a cause of outbreaks. In 2018, the Brazilian state of São Paulo witnessed a new YF outbreak in areas where the virus has not been detected before. OBJECTIVE The aim is to describe the clinical and laboratorial characteristics of severe cases of YF, evaluate viral to determine markers associated with fatal outcome. METHODS Acute severe YF cases (n = 62) were admitted to the Intensive Care Unit of a reference hospital and submitted to routine laboratorial evaluation on admission. YFV-RNA was detected in serum and urine by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and then sequenced. Patients were classified in two groups: survival or death. FINDINGS In the univariate analysis the following variables were associated with outcome: alanin aminotransferase (ALT), aspartat aminotransferase (AST), AST/ALT ratio, total bilirubin (TB), chronic kidney disease epidemiology collaboration (CKD-EPI), ammonia, lipase, factor V, international normalised ratio (INR), lactate and bicarbonate. Logistic regression model showed two independent variables associated with death: lipase [odds ratio (OR) 1.018, 95% confidence interval (CI) 1.007 to 1.030, p = 0.002], and factor V (OR -0.955, 95% CI 0.929 to 0.982, p = 0.001). The estimated lipase and factor V cut-off values that maximised sensitivity and specificity for death prediction were 147.5 U/L [area under the curve (AUC) = 0.879], and 56.5% (AUC = 0.913). MAIN CONCLUSIONS YF acute severe cases show a generalised involvement of different organs (liver, spleen, heart, kidneys, intestines and pancreas), and different parameters were related to outcome. Factor V and lipase are independent variables associated with death, reinforcing the importance of hemorrhagic events due to fulminant liver failure and pointing to pancreatitis as a relevant event in the outcome of the disease.

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.

Paciente con trombosis venosa profunda recidivante por factor V Leiden y respuesta al tratamiento homeopático / Patient with recurrent deep venous thrombosis by factor V Leiden and response to homeopathic treatment

El tromboembolismo venoso (TEV) es un problema de salud significativo, con morbimortalidad cercana al 30%. El factor V Leiden (FVL) es una forma "mutada" del factor V normal que se inactiva 10 veces más lentamente, produciendo estados de hipercoagulación y trombosis. En este artículo se presenta el caso de una mujer de 23 años de edad en quien, a raíz de un episodio de TVP se diagnosticó su condición de portadora de enfermedad por FVL de carácter homocigota. Transcurridos 8 años del primer episodio y estando aún bajo tratamiento convencional, el alto nivel de dímeroD (DD) señalaba alto riesgo de sufrir nuevos episodios de TVP. En ese momento se inició tratamiento con medicación homeopática unicista constitucional, en baja dinamización y dosis diarias, observándose una rápida caída en las cifras de DD cambiando así el pronóstico de futuras recidivas y llevando a los hematólogos a suspender el tratamiento convencional. No hubo recidivas hasta el presente y el Doppler venoso muestra rehabilitación del lecho venoso. (AU)

Venous thromboembolism (VTE) is a significant health problem with morbidity and mortality around 30%. Factor V Leiden (FVL) is a "mutated" form of the normal factor V which is inactivated 10 times slower causing hypercoagulation states and thrombosis. The present articles describes the case of a 23-year-old women in whom that status of homozygous was diagnosed on the occasion of a VTE episode. High dimer-D (DD) levels 8 years later and still under conventional treatment high pointed to high risk for recurrence of VTE. Homeopathic treatment was started (constitutional unicast) in low potency and daily doses. DD fell rapidly, and thus the prognosis changed, leading hematologists to withdraw conventional treatment. Disease did not relapse to this day and venous Doppler sonography evidenced rehabilitated vein system. (AU)

Paciente con trombosis venosa profunda recidivante por factor V Leiden y respuesta al tratamiento homeopático / Patient with recurrent deep venous thrombosis by factor V Leiden and response to homeopathic treatment

El tromboembolismo venoso (TEV) es un problema de salud significativo, con morbimortalidad cercana al 30%. El factor V Leiden (FVL) es una forma "mutada" del factor V normal que se inactiva 10 veces más lentamente, produciendo estados de hipercoagulación y trombosis. En este artículo se presenta el caso de una mujer de 23 años de edad en quien, a raíz de un episodio de TVP se diagnosticó su condición de portadora de enfermedad por FVL de carácter homocigota. Transcurridos 8 años del primer episodio y estando aún bajo tratamiento convencional, el alto nivel de dímeroD (DD) señalaba alto riesgo de sufrir nuevos episodios de TVP. En ese momento se inició tratamiento con medicación homeopática unicista constitucional, en baja dinamización y dosis diarias, observándose una rápida caída en las cifras de DD cambiando así el pronóstico de futuras recidivas y llevando a los hematólogos a suspender el tratamiento convencional. No hubo recidivas hasta el presente y el Doppler venoso muestra rehabilitación del lecho venoso. (AU)

Venous thromboembolism (VTE) is a significant health problem with morbidity and mortality around 30%. Factor V Leiden (FVL) is a "mutated" form of the normal factor V which is inactivated 10 times slower causing hypercoagulation states and thrombosis. The present articles describes the case of a 23-year-old women in whom that status of homozygous was diagnosed on the occasion of a VTE episode. High dimer-D (DD) levels 8 years later and still under conventional treatment high pointed to high risk for recurrence of VTE. Homeopathic treatment was started (constitutional unicast) in low potency and daily doses. DD fell rapidly, and thus the prognosis changed, leading hematologists to withdraw conventional treatment. Disease did not relapse to this day and venous Doppler sonography evidenced rehabilitated vein system. (AU)

Determinación de valores de referencia para factor V de la coagulación en una población pediátrica / Determination of reference ranges for factor V of coagulation in a pediatric population / Determinação de valores de referência para provas de factor V da coagulação em uma população pediátrica

El sistema hemostático varía a lo largo de las primeras etapas de vida como consecuencia de cambios que ocurren durante el crecimiento. Los trabajos de investigación que estudian valores de referencia en niños para los factores de la coagulación son escasos y por ello la necesidad de estudiarlos. El presente es un trabajo retrospectivo que se realizó sobre 142 niños de hasta 17 años que concurrieron al hospital, de los cuales se obtuvieron los valores de factor V (FV). Los resultados, teniendo en cuenta el percentilo 97,5, mostraron diferencias significativas para la determinación del mismo. Es importante que cada laboratorio establezca sus propios valores de referencia para estas pruebas ya que no son extrapolables a los de los adultos. En este estudio se demuestra que el sistema hemostático sufre modificaciones durante la infancia que deben ser tenidas en cuenta para interpretar correctamente los resultados de las pruebas realizadas...

Dilataciones endoscópicas del tracto gastrointestinal / Endoscopic dilation of the gastrointestinal tract

Las dilataciones en el tracto gastrointestinal se llevan a cabo para aliviar la obstrucción sintomática, ya sea funcional u orgánica, secundarias a una variedad de patologías tanto benignas como malignas. Con el advenimiento de las nuevas tecnologías, virtualmente toda estenosis digestiva puede ser manejada en forma mínimamente invasiva. Pese a su amplia difusión en la práctica actual, existen pocos estudios controlados que comparen las diferentes modalidades de dilatación. En el presente artículo realizamos una revisión de esta técnica, así como de la evidencia disponible para su aplicación en los diferentes segmentos del tracto gastrointestinal. El futuro de la dilatación incluye el desarrollo de dilatadores que permitan evaluar la dilatación durante su realización. Estos advenimientos, así como la ejecución de estudios controlados prospectivos van a mejorar las indicaciones, beneficios y riesgos para cada uno de los sistemas de dilatación existentes.

The endoscopic dilation of the gastrointestinal tract is carried out to relieve either functional or organic disorders, secondary to a variety of both benign and malignant diseases. With the advent of new technologies, virtually all digestive stenosis can be managed in a minimally invasive way. Despite its wide dissemination in actual practice, there are few controlled studies comparing the different forms of endoscopic dilation. In this article, we review this technique and the evidence available for application in different segments of the gastrointestinal tract. The future of the dilations includes the development of dilators to assess dilation during the procedure. These advents and the implementation of prospective controlled studies will improve the indications, benefits and risks for each of the existing systems of dilations.

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.

Genotipos frecuentemente asociados a trombofilias / Frequently associated genotypes to thrombophilia

La enfermedad tromboembólica venosa es una entidad patológica importante debido a la morbilidad que causa, por sus complicaciones y por su alta incidencia en el mundo, la cual puede variar desde 1:100 en adultos mayores hasta 1:100.000 en niños. Existen múltiples factores de riesgo tanto genéticos como ambientales asociados a la enfermedad; los más ampliamente estudiados por su incidencia en la población mundial son el factor V de Leiden, la mutación G20210A en el factor II (protrombina) y las mutaciones en la metilen-tetrahidrofolato reductasa C677T y A1298C, que hasta hace poco se consideraban factores de riesgo. En la presente revisión se presenta de forma concisa qué es y cómo se produce un trombo a partir de la enfermedad tromboembólica, cuáles son las principales entidades nosológicas que involucra la enfermedad y los genotipos más frecuentemente asociados a la misma. Se enfatiza en las alteraciones genéticas epidemiológicamente más importantes y se muestran brevemente los estudios realizados en Colombia.

Venous thromboembolism is an important pathological entity that causes high morbidity due either to the disease or its complications. The incidence in the world ranges between 1:100 in adults and 1:100,000 in children. Risk factors for the disease include genetic as well as environmental factors. Among them, factor V Leiden (G1691A), prothrombin (G20210A) and MTHFR C677T and A1298C (which until recently were considered risk factors), have been widely studied given their impact in the world. This review presents in a clear and concise way what a thrombous is and how it is formed; how a clot is able to produce thromboembolic disease; what are the main nosological entities involved, and their main genetic causes. The most epidemiologically important genetic alterations and studies conducted in Colombia will be emphasized.

Leishmania amazonensis exhibits phosphatidylserine-dependent procoagulant activity, a process that is counteracted by sandfly saliva

Leishmania parasites expose phosphatidylserine (PS) on their surface, a process that has been associated with regulation of host's immune responses. In this study we demonstrate that PS exposure by metacyclic promastigotes of Leishmania amazonensis favours blood coagulation. L. amazonensis accelerates in vitro coagulation of human plasma. In addition, L. amazonensis supports the assembly of the prothrombinase complex, thus promoting thrombin formation. This process was reversed by annexin V which blocks PS binding sites. During blood meal, Lutzomyia longipalpis sandfly inject saliva in the bite site, which has a series of pharmacologically active compounds that inhibit blood coagulation. Since saliva and parasites are co-injected in the host during natural transmission, we evaluated the anticoagulant properties of sandfly saliva in counteracting the procoagulant activity of L. amazonensis . Lu. longipalpis saliva reverses plasma clotting promoted by promastigotes. It also inhibits thrombin formation by the prothrombinase complex assembled either in phosphatidylcholine (PC)/PS vesicles or in L. amazonensis . Sandfly saliva inhibits factor X activation by the intrinsic tenase complex assembled on PC/PS vesicles and blocks factor Xa catalytic activity. Altogether our results show that metacyclic promastigotes of L. amazonensis are procoagulant due to PS exposure. Notably, this effect is efficiently counteracted by sandfly saliva.

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.

Genetic polymorphisms and cerebrovascular disease in children with sickle cell anemia from Rio de Janeiro, Brazil / Polimorfismos genéticos e doença cerebrovascular em crianças com anemia falciforme do Rio do Janeiro, Brasil

The aim of the present work was to examine possible genetic risk factors related to the occurrence of cerebrovascular disease (CVD) in Brazilian population, the frequency of βS-globin gene haplotypes and co-inheritance with α-thalassemia (-α3.7kb) and single nucleotide polymorphism of methylenetetrahydrofolate reductase (MTHFR-C677T), Factor V Leiden (FV-G1691A) and prothrombin (PT-G20210A) genes in children from Rio de Janeiro. Ninety four children with sickle cell anemia (SCA) were included, 24 patients with cerebrovascular involvement and 70 patients without CVD as control group. The mean age of children at the time of the cerebrovascular event was similar to the control group. The frequency of -α3.7kb thalassemia was similar in both groups (p=0.751). Children with Bantu/Atypical βS-globin gene haplotype presented 15 times more chance (OR=15.4 CI 95 percent 2.9-81.6) of CVD than the other βS-globin gene haplotypes. The C677T polymorphism of MTHFR gene was similar in both groups (p=0.085). No mutation in the FV Leiden or PT genes was found. A large study seems necessary to establish the role of these genetic polymorphisms in Brazilian miscegenated population.

Avaliar o papel da talassemia alfa (-α3.7kb), dos haplótipos da globina βS, e mutações nos genes da metileno-tetrahidrofolato redutase (MTHFR-C677T), fator V de Leiden (FV-G1691A) e protrombina (PT-G20210A) como fatores de risco para a doença cerebrovascular em pacientes com anemia falciforme. Foi realizado um estudo de caso controle com 94 crianças portadoras de anemia falciforme, 24 com doença cerebrovascular (DCV) e 70 sem DCV como grupo controle. A frequência de talassemia -α3.7kb foi semelhante em ambos os grupos (p=0,751). Crianças portadoras do haplótipo Bantu/Atípico da globina βS apresentam 15 vezes mais chances de desenvolverem DCV (OR=15,4 IC 95 por cento 2,9-81,6) do que os outros haplótipos. A frequência do polimorfismo MTHFR-C677T foi semelhante em ambos os grupos (p=0,085) e não foi observada mutação nos genes fator V e protrombina. Estudos com maior número de casos são necessários para esclarecer o papel desses polimorfismos genéticos na nossa população.

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.

Resistência à proteína C ativada e doença arterial isquêmica em jovem / Resistance to activated protein C and ischemic arterial disease in a young man

A avaliação da resistência à ação da proteína C ativada (rPCA), causada por mutação no fator V (fator V de Leiden), é fator de risco importante para tromboembolia venosa, cujo papel como geradora de obstruções arteriais in situ é um tema ainda controverso. O caso clínico de um jovem com história de coronariopatia, múltiplas lesões cerebrovasculares e doença arterial periférica é relatado. A investigação diagnóstica apontou a rPCA como possível etiologia.

The assessment of activated protein C resistance (APCR) caused by mutations in factor V (factor V Leiden) is an important risk factor for venous thromboembolism, of which role as the originator of arterial obstructions in situ is still a controversial subject. The clinical case of a young patient with history of coronariopathy, multiple cerebrovascular lesions and peripheral artery disease is reported. The diagnostic investigation showed APCR as the possible etiology.

Variante protrombótica C677T del gen metilenotetrahidrofolato reductasa es un biomarcador molecular de fallas de implantación en mujeres chilenas sometidas a protocolos de reproducción asistida / Prothrombotic variant C677T at the methylenetetrahydrofolate reductase gene is a molecular biomarker of implantation failure in chilean women undergoing assisted reproductive protocols

Las fallas de implantación son consideradas una importante causa de infertilidad en mujeres sometidas a protocolos de Fecundación Asistida. Evidencia reciente sugiere que la presencia de variantes protrombóticas está asociada a diversos defectos obstétricos y falla reproductiva. Sin embargo, los resultados en diversas poblaciones son contradictorios. De acuerdo a esta evidencia, se evaluó la potencial asociación entre variantes protrombóticas y fallas de implantación en mujeres chilenas incluidas en protocolos de fecundación asistida. Un total de 180 mujeres, 80 pacientes sometidas a protocolos de reproducción asistida y 100 controles fueron incluidas en este estudio. La genotipificación molecular de variantes protrombóticas en genes candidatos fue realizada por PCR-RFLP. Observamos una paciente heterocigota para la variante F5 G1691A y ausencia total del polimorfismo F2 G20210A en pacientes y controles. La distribución genotípica y la distribución relativa de alelos del polimorfismo MTHFR C677T fueron significativamente diferentes entre pacientes y controles. Odds Ratio para fallas de implantación asociadas al genotipo homocigoto fue 2,78 (95 por ciento IC 1,147 - 6,755; p= 0,0199). En resumen, nuestros resultados sugieren que la variante MTHFR C677T constituye un biomarcador molecular de susceptibilidad a fallas de implantación población chilena.

Implantation failures are considered an important cause of infertility in women undergoing assisted reproductive protocols. Recent evidence suggests that the presence of prothrombotic variants is associated with obstetric defects and reproductive failure. However, results between several populations are contradictory. According this evidence, we evaluated the potential association between prothrombotic variants and implantation failure susceptibility in Chilean women undergoing Assisted Reproductive protocols. 180 women, 80 patients undergoing assisted reproductive protocols and 100 controls were included in this study. Molecular genotyping of prothrombotic variants in candidate genes was realized by PCR-RFLP. We observed one patient heterozygote for factor V G1691A variant, and total absence to prothrombin G20210A polymorphism in patients and controls. Genotype distribution and allelic frequencies of MTHFR C677T polymorphism were significantly different between patients and controls (p<0.05). Odss Ratio for implantation failure associated to homozygote genotype was 2.78 (95 percent IC 1.147 ¡ 6.755; p= 0.0199). In summary, our data suggest that the MTHFR C677T polymorphism constituted a molecular biomarker of implantation failure susceptibility in Chilean population.

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.

Fator V de Leiden na doença de Legg-Calvé-Perthes / Leiden's V-factor in Legg-Calvé-Perthes disease

Trobofilias hereditárias têm sido implicadas na patogênese da doenca de Legg-Calvé-Perthes. Uma investigação do fator de risco hereditário mais comum para hipercoagulabilidade - a mutação no gene do fator V (fator V de Leiden) - foi conduzida em 20 pacientes com Legg-Calvé-Perthes e 214 controles sadios. A prevalência do fator V de Leiden foi maior nos pacientes com Legg-Calvé-Perthes que no grupo controle (30 vs. 1,87 por cento). A razão de chances (odds ratio) para o desenvolvimento de Legg-Calvé-Perthes foi de 22,5 (p<0,05; intervalo de confiança: 5,68- 89.07). Estes dados sugerem, o fator V de Leiden como fator de risco hereditário para hipercoagulabilidade associada ao desenvolvimento da doença de Legg-Calvé-Perthes.

Inherited tendency to hypercoagulability has been suggested as a cause of vascular thrombosis resulting in Legg-Calvé-Perthes disease. An investigation of the most common inherited risk factor for hypercoagulability - the mutation in the V-factor gene (Leiden's V-factor) - was carried out among 20 Patients diagnosed with Legg- Calvé-Perthes disease. Patients were compared with 214 healthy controls. The prevalence of the Leiden's V-factor was higher in patients with Legg-Calvé-Perthes disease than in controls (30 percent vs. 1,87 percent). The odds ratio for the development of Legg-Calvé-Perthes disease in the presence of the Leiden's V-factor mutation was 22,5 (p<0,05; confidence interval: 5,68-89.07). These data suggest the Leiden's V-factor as an inherited risk factor for hypercoagulability associated with the development of Legg-Calvé-Perthes disease.

Low prevalence of Factor V Leiden and the prothrombin G20210A mutation in a healthy population from the central-south region of Chile / Baixa prevalência do Fator V Leiden e da mutação da protrombina G20210A em uma população sã da região centro-sul do Chile

Thrombosis is a result of the interaction between predisposing genetic polymorphisms and acquired risk factors. The two prothrombotic polymorphisms which are most frequently associated with thrombosis are factor V (FV) Leiden and the prothrombin (PT) G20210A mutation. The objective of this work was to investigate the prevalence of both factors in the central-south region of Chile. Determination of the frequency was carried out by means of a genetic analysis of 1200 healthy, non-native individuals. The mutation of FV Leiden was found in 1.25 percent of the population and the PT G20210A mutation in 1.33 percent. None of the individuals were homozygosis or had both polymorphisms. The prevalences of FV Leiden and the PT G20210A mutation are less common in the healthy population.

A trombose pode ser o resultado da interação de polimorfismo genético e fatores de riscos adquiridos. Os polimosfirmos protrombóticos mais frequentes são fator V (FV) Leiden e a mutação da protrombina (PT) G20210A. O objetivo deste trabalho foi investigar a prevalência de ambos os polimorfismos na região centro-sul do Chile. Foram realizadas análises genéticas (PCR RFLP) de 1.200 pessoas saudáveis, não nativas da região. Foram encontrados 1,25 por cento de mutação do Fator V Leiden e 1,33 por cento da mutação da protrombina G20210A. Não foi detectada homozigose em ambos os polimorfismos. A prevalência de FV Leiden e da mutação G20210A é baixa na população estudada.