Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034065 (pulmonary embolism)
 14,979 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Activated protein C resistance caused by factor V Leiden mutation is the most common inherited cause of an underlying predisposition to pulmonary embolism (PE) and deep venous thrombosis (DVT). We studied the frequency of the factor V Leiden mutation in 50 women who had PE and/or DVT during or after pregnancy or during oral contraceptive use. Ten (20%; 95% CI 10% to 34%) of the 50 women were heterozygous for the mutation. First-trimester PE or DVT developed in 6 (60%; 95% CI, 26% to 88%) of the 10 women with the mutation compared with 3 (8%; 95% CI 2% to 20%) of 40 women without the mutation (p = 0.0009). These data indicate that the factor V Leiden mutation is an important risk factor for PE or DVT during pregnancy (especially the first trimester), after pregnancy, or during oral contraceptive use.
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PMID:Pulmonary embolism and deep venous thrombosis during pregnancy or oral contraceptive use: prevalence of factor V Leiden. 864 93

Multiple risk factors for thrombosis were found in a 21 year old female who experienced three episodes of premature labor and developed severe pulmonary embolism during her third pregnancy. This patient is heterozygous for factor V Leiden mutation and homozygous for methylenetetrahydrofolate reductase (MTHFR) gene nucleotide 677 C to T (C677T) point mutation. This is a first report of the concordance of homozygous MTHFR C677T mutation in an individual with factor V Leiden mutation. This new case provides further evidence that synergism of multiple genetic and acquired risk factors is often encountered in young patients with symptomatic venous thrombosis.
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PMID:Pulmonary embolism and premature labor in a patient with both factor V Leiden mutation and methylenetetrahydrofolate reductase gene C677T mutation. 884 Apr 66

The diagnostic strategies and clinical characteristics of thrombophilia associated with heterozygous or homozygous factor V Leiden mutation have been determined according to the literature and to a personal study in 51 families. Factor V mutation was present in the 51 propositi and in 84 out of 125 family members (81 heterozygous, 3 homozygous). Venous thrombosis was observed in all the propositi, in 17 of the 84 family members with the mutation and in 6 of the 41 with a normal APC resistance test and no mutation. An associated protein C or protein S deficiency was present in 5 families (10%). The most frequent clinical manifestations were superficial or deep vein thrombosis and/or pulmonary embolism, but also thrombosis at an unusual site (cerebral, mesenteric or central retinal vein). A causal relationship is frequently difficult to demonstrate. A precipitating factor was observed in 84% of cases and a recurrent thrombotic episode occurred in 50% of propositi. The risk of thrombosis associated with pregnancy was high in the post-partum period, especially in homozygous women. In the 28 homozygous subjects, markers of coagulation activation were frequently elevated in untreated patients. Finally, the efficacy of anticoagulant treatment is suggested but the long period often observed between treatment interruption and a recurrence does not militate in favour of long term treatment.
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PMID:Diagnosis and clinical characteristics of inherited activated protein C resistance. 897 37

Thromboprophylaxis with oral anticoagulants up to six months is established in patients after a first venous thromboembolic event (VTE). The risk of recurrent VTE is still considerable thereafter, and it is uncertain whether some patients might benefit from extended anti-coagulation. We performed a prospective, multicenter trial (4 thrombosis centers) and evaluated in 380 patients with a first or recurrent VTE (patients with a deficiency of antithrombin, protein C, protein S or plasminogen; cancer; or an antiphospholipid antibody syndrome were excluded) the risk of recurrence after discontinuation of secondary thromboprophylaxis with oral anticoagulants. It was the aim of the study to evaluate whether patients, with factor V Leiden are at an increased risk of recurrent VTE. 112 (29.5%) patients were carriers of factor V Leiden (26.9% heterozygous, 2.6% homozygous). After a median observation time of 19.3 months the overall recurrence rate of VTE was 9.9%. Recurrent deep vein thrombosis and/or pulmonary embolism occurred in 26 of 268 patients without factor V Leiden (9.7%) and in 10 of 112 patients with factor V Leiden (8.9%). The probability of recurrent VTE two years after discontinuation of oral anticoagulants was 12.4% (95% CI 7.8-17) in patients without factor V Leiden and was 10.6% (95% CI 3.8-17.4) in carriers of the mutation. This difference was statistically not significant. Patients with factor V Leiden are not at a higher risk of recurrent VTE within two years after discontinuation of oral anticoagulants than patients without factor V Leiden. Balancing the risk of recurrent VTE and bleeding from oral anticoagulants, patients with factor V Leiden are not likely to benefit from oral anticoagulant therapy extended beyond six months.
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PMID:The risk of recurrent venous thromboembolism in patients with and without factor V Leiden. 913 32

Venous thromboembolism is a serious, potentially lethal health problem affecting one per 1,000 people annually. Major surgery, the use of oral contraceptives, complicated pregnancy, fractures, and immobilization increase the risk of thrombosis. In addition to these factors, thrombosis is associated with inherited deficiencies of antithrombin III, protein C, and protein S. Together these do not account for more than five to 10% of the cases. Hereditary activated protein C resistance has been recognized as a basis for a majority of cases of familial thrombosis. It accounted for more than a 10 times higher number than that of other known genetic defects. We describe a case of a young female who presented with a pulmonary embolism and was discovered to have activated protein C resistance. This patient had a heterozygous mutation for factor V Leiden and was taking oral contraceptives. This report underlines: 1) increased risk of venous thrombosis in oral contraceptive users who carry factor V Leiden mutation associated with functional resistance to the normal anticoagulation activities of protein C; 2) most episodes occurring in the young are minor, but pulmonary embolus can occur; 3) the importance of identifying other affected members of the family; and 4) the importance of anticoagulation prophylaxis at times of enhanced risk, particularly during pregnancy, postpartum, and major surgery.
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PMID:Life threatening pulmonary embolus in a factor V Leiden carrier on oral contraceptives: a case report. 923 27

The effect of antiphospholipid antibodies (aPL) on the action of activated protein C (APC) was examined in 32 patients: 19 with lupus anticoagulant (LA), 6 with anticardiolipin antibodies (aCL), and 7 with LA and aCL. Eighteen patients had a ratio of activated partial thromboplastin time (APTT) with APC to APTT without APC (APTT ratio) <2.06 (cut-off level) and no factor V Leiden mutation; these patients showed APC-resistance (APC-R) phenotype. The mean prolongation of APTT after addition of APC in a control group was 45.3 seconds, with a lower limit of 31.4 seconds. Only 3 of the 18 patients with low APTT ratio had a prolongation of <31.4 seconds; they were classified as true APC-R phenotype, whereas the other 15 patients were classified as spurious APC-R. Of the 3 patients with true APC-R, 2 had deep venous thrombosis, 1 with pulmonary embolism, and the third had recurrent abortion. Of the other 15 patients, 2 had had ischemic stroke, 1 had recurrent abortion, and 12 were asymptomatic. Circulating APC level was measured in 14 of the 18 aPL patients with a low APTT ratio; it was lower than the normal lower limit in 4 patients and within the lower limit in 2. Three of the 4 patients with reduced APC levels had a history of thrombosis. We conclude that patients with aPL who show APC-R phenotype due to a low APTT ratio without the factor V Leiden mutation can be classified into two groups: true and spurious APC-R phenotype. Since those with true APC-R phenotype could have greater thrombotic risk, adequate classification of these patients is important. Moreover, aPL can sometimes interfere with the activation of protein C, thus reducing the circulating levels of APC, and this could constitute another thrombotic risk factor.
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PMID:Activated protein C resistance phenotype in patients with antiphospholipid antibodies. 928 Jan 48

To determine whether factor V Leiden is associated with thrombotic events in patients with heparin-induced thrombocytopenia (HIT), we evaluated 165 patients with serologically confirmed HIT for the presence of factor V Leiden and determined the incidence of venous or arterial thrombosis during the period of HIT. Factor V Leiden was detected in 16 of 165 HIT patients (9.7%). HIT-associated venous thrombosis occurred in 11 of 16 factor V Leiden positive subjects and 94 of 149 factor V Leiden negative subjects (69% vs. 63%; p = 0.79). Arterial thrombosis occurred in 1 of 16 factor V Leiden positive subjects and 21 of 149 factor V Leiden negative subjects (6% vs. 14%; p = 0.70). There was no difference in the incidence of proximal limb DVT, pulmonary embolism, venous limb gangrene, local skin reactions, hemorrhagic adrenal infarction, stroke, or myocardial infarction between the groups. No difference in the severity of venous thrombosis between Leiden positive and negative subjects was detected. Our data suggest that in the acute prothrombotic milieu of HIT, heterozygous factor V Leiden is not an important additional risk factor for thrombosis.
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PMID:Factor V Leiden and thrombotic complications in heparin-induced thrombocytopenia. 945 22

Severe hyperhomocysteinemia in its most frequent form, is caused by a homozygous enzymatic deficiency of cystathionine beta-synthase (CBS). A major complication in CBS deficiency is deep venous thrombosis or pulmonary embolism. A recent report by Mandel et al (N Engl J Med 334:763, 1996) postulated factor V Leiden (FVL) to be an absolute prerequisite for the development of thromboembolism in patients with severe hyperhomocysteinemia. We studied 24 patients with homocystinuria caused by homozygous CBS deficiency from 18 unrelated kindreds for FVL and for the 677C-->T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene and investigated their possible interaction in the risk of venous thrombosis. Thrombotic complications were diagnosed in six patients, of whom only one was a carrier of FVL. On the contrary, thermolabile MTHFR caused by the 677C-->T mutation, was frequently observed among homocystinuria patients, especially among those with thromboembolic complications: three of six homocystinuria patients who had suffered from a thromboembolic event had thermolabile MTHFR. These data indicate that FVL is not an absolute prerequisite and probably not even a major determinant of venous thrombosis in homocystinuria, but, interestingly, thermolabile MTHFR may constitute a significant risk factor for thromboembolic complications in this inborn error of methionine metabolism.
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PMID:Homozygous cystathionine beta-synthase deficiency, combined with factor V Leiden or thermolabile methylenetetrahydrofolate reductase in the risk of venous thrombosis. 949 Jun 85

Leiden mutation of the coagulation factor V is the most frequent known congenital risk factor of thrombophilia. The authors examined a group of 440 subjects with thrombosis in the case- or family-history. The mutation was found in 146. In 94 thrombotic manifestations were recorded in the case-history, five women were examined because of repeated abortions. 52.74% carriers of FVL had venous thrombosis of the lower extremities and pelvis in their case-history, 19.18% had pulmonary embolism in the case-history. In 27.40% during the initial manifestations of thrombosis no other risk factor of thrombosis was detected. In 10.27% the first thrombosis developed after an injury or operation. In 22.22% women the thrombosis was manifested during pregnancy or the puerperal period. Due to the high incidence of this defect screening of the resistance to activated protein C should be an integral part of examination of thrombophil conditions.
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PMID:[Clinical findings in individuals with the factor V Leiden mutation]. 960 52

Standard therapy for patients with deep venous thrombosis and pulmonary embolism typically includes anticoagulation for a 3-6 month period with full dose warfarin. However, patients following this regimen experience high rates of recurrent thrombosis, re-hospitalization and mortality in the years immediately following cessation of anticoagulation. This is true for patients at average risk of disease recurrence, and for patients at elevated risk due to the presence of inherited defects of anticoagulation such as factor V Leiden mutation. Unfortunately, no clinical regimen currently available has proven to have sufficient benefit to support long-term prophylaxis. In particular, full dose warfarin is associated with substantially increased risks of hemorrhage when used on a long term basis. In contrast, while targeted low-dose warfarin (INR 1.5-2.0) is safe for long-term therapy, the efficacy of this approach in the prevention of recurrent venous thromboembolic disease has remained untested. The Prevention of Recurrent Venous Thromboembolism (PREVENT) trial will evaluate the efficacy of prolonged treatment with low-dose warfarin in the secondary prevention of venous thromboembolism (VTE). Patients with a history of documented idiopathic venous thrombosis who have completed a standard course of anticoagulation therapy will be enrolled in a randomized, double-blind, placebo-controlled trial comparing usual care plus targeted low-dose warfarin to usual care plus placebo for a period of up to 4 years. Trial endpoints will include recurrent VTE, major bleeding episodes and all-cause mortality in the total patient population and separately in those patients with factor V Leiden. The potential clinical impact of the PREVENT trial is broad since a positive finding would strongly support chronic low-intensity anticoagulation among patients with venous thrombosis who are at risk for recurrence following cessation of standard outpatient anticoagulation.
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PMID:Long-term, low-dose warfarin among venous thrombosis patients with and without factor V Leiden mutation: rationale and design for the Prevention of Recurrent Venous Thromboembolism (PREVENT) trial. 966 36


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