The diagnosis of factor V Leiden thrombophilia is established in a proband by identification of a heterozygous or homozygous c.1691G>A variant (referred to as the factor V Leiden variant in <i>F5</i>, the gene encoding factor V) in conjunction with coagulation tests such as the APC resistance assay.
Also, in comparison with patients with LDVT carrying GG genotype of FV gene 1691G>A polymorphism, the following activities reduced significantly: prothrombin time, activated partial thromboplastin time, fibrinogen, protein C, and protein S, while activated protein C resistance and lupus anticoagulant positive rate increased in patients carrying A allele (GA + AA).
The incidence of activated protein C resistance caused by the mutation of factor V Leiden was in six patients (5.9%) with adverse pregnancy outcomes, and in four patients (6.6%) from the control group.
In both the ex vivo and in vitro studies dabigatran interfered significantly with activated protein C resistance ratios observed in normal subjects and in factor V Leiden heterozygous carriers.
The associations of the following mutations in inherited thrombophilias and IVF outcomes were explored: factor V Leiden (FVL), prothrombin gene G20210A mutation (PGM), 5,10-methylentetrahydrofolate reductase (MTHFR) C677T, MTHFR (A1298C) and activated protein C resistance (APCR).
The difference of homocysteine, folate, vitamin B12, antithrombin III activity, protein C activity, free protein S activity, and activated protein C resistance were not statistically significant; and the number of subjects with MTHFR C677T, prothrombin G20210A, and factor V Leiden mutations were similar between the study groups.
High APC resistance was associated with breast cancer in both factor V Leiden non-carriers (OR 6.5, 95% CI 4.1-10.4) and carriers (OR 38.3, 95% CI 6.2-236.6).
We found association between LEDVT and factor V Leiden ([FVL]; OR: 1.8; 95% CI 1.4-2.4) and resistance to activated protein C ([APC-R]; OR: 1.6; 95% CI 1.1-2.4).
APC resistance due to Factor V Leiden is not related to baseline inflammatory mediators or survival up to 10 years in patients with critical limb ischemia.
The screening for thrombophilia included mutations of factor V Leiden (FVL), prothrombin (PTM) G20210A, methylene tetrahydrofolate reductase C677T-A1298C, the serum levels of antithrombin III, protein C, protein S, factor VIII and activated protein C resistance.
Testing for hereditary thrombophilia typically includes tests for activated protein C resistance (APC-R) and/or factor V Leiden, protein C, protein S, antithrombin, and prothrombin G20210A.
We wanted to investigate whether APC resistance in the absence of factor V Leiden, determined with global coagulation test such as the thrombin generation assay, could be used as a marker for increased risk of recurrent VTE among women 18-65 years old after a first event of VTE.
Myocardial infarction (MI) can be due to inherited thrombophilia caused by resistance to activated protein C resulting from factor V Leiden (FVL) mutation.
Secondly, resistance to activated protein C as a result of factor V Leiden is associated with thromboembolic disease at an early age (Price DT, Ridker PM.Ann Intern Med.1997;127:895-903).
Congenital risk factors include deficiencies or defects in natural anticoagulants, such as antithrombin, Protein C and Protein S, and genetic polymorphisms such as prothrombin G20210A and cleavage-resistant forms of factor V (in particular factor V Leiden), that lead to a condition commonly known as activated protein C resistance.
One of the most frequent hereditary causes of thrombophilia is, without a doubt, resistance to Activated Protein C (APC-resistance), which is a consequence of point mutation in gene coding for coagulation Factor V (Factor V Leiden) in 90-95% of cases.
However, contrary to common expectations, factor V Leiden was observed much less frequently in patients showing activated protein C resistance (10 out of 23; 43.4%) than is commonly observed in the Caucasian population (almost 90%).
In addition, abnormal activated protein C resistance (or Factor V Leiden), Factor II G20219A variant, and the thermolabile variant of methylenetetrahydrofolate reductase (MTHFR C677T) need to be considered.
Thrombophilia was suspected and the relative investigation revealed high levels of factor VIII procoagulant, which is frequent in hemodialysis patients, and resistance to activated protein C. Polymerase chain reaction detected that the patient was heterozygous for factor V Leiden, which is quite common in general population.