scholarly journals Expression of the normal factor V allele modulates the APC resistance phenotype in heterozygous carriers of the factor V Leiden mutation

2005 ◽  
Vol 3 (12) ◽  
pp. 2695-2702 ◽  
Author(s):  
J. M. BRUGGE ◽  
P. SIMIONI ◽  
F. BERNARDI ◽  
D. TORMENE ◽  
B. LUNGHI ◽  
...  
Keyword(s):  
Factor V Leiden ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Resistance Phenotype ◽  
Apc Resistance ◽  
Heterozygous Carriers

“Pseudo Homozygous” Activated Protein C Resistance due to Double Heterozygous Factor V Defects (Factor V Leiden Mutation and Type I Quantitative Factor V Defect) Associated with Thrombosis: Report of Two Cases Belonging to Two Unrelated Kindreds

1996 ◽  
Vol 75 (03) ◽  
pp. 422-426 ◽  
Author(s):  
Paolo Simioni ◽  
Alberta Scudeller ◽  
Paolo Radossi ◽  
Sabrina Gavasso ◽  
Bruno Girolami ◽  
...  
Keyword(s):  
Protein C ◽  
Dna Analysis ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Type I ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Thrombotic Risk ◽  
Apc Resistance ◽  
Quantitative Factor

SummaryTwo unrelated patients belonging to two Italian kindreds with a history of thrombotic manifestations were found to have a double heterozygous defect of factor V (F. V), namely type I quantitative F. V defect and F. V Leiden mutation. Although DNA analysis confirmed the presence of a heterozygous F. V Leiden mutation, the measurement of the responsiveness of patients plasma to addition of activated protein C (APC) gave results similar to those found in homozygous defects. It has been recently reported in a preliminary form that the coinheritance of heterozygous F. V Leiden mutation and type I quantitative F. V deficiency in three individuals belonging to the same family resulted in the so-called pseudo homozygous APC resistance with APC sensitivity ratio (APC-SR) typical of homozygous F. V Leiden mutation. In this study we report two new cases of pseudo homozygous APC resistance. Both patients experienced thrombotic manifestations. It is likely that the absence of normal F. V, instead of protecting from thrombotic risk due to heterozygous F. V Leiden mutation, increased the predisposition to thrombosis since the patients became, in fact, pseudo-homozygotes for APC resistance. DNA-analysis is the only way to genotype a patient and is strongly recommended to confirm a diagnosis of homozygous F. V Leiden mutation also in patients with the lowest values of APC-SR. It is to be hoped that no patient gets a diagnosis of homozygous F. V Leiden mutation based on the APC-resi-stance test, especially when the basal clotting tests, i.e., PT and aPTT; are borderline or slightly prolonged.

APC-RESISTANCE ASSOCIATED WITH FACTOR V LEIDEN GENE MUTATION (GENOTYPE GA): CLINICAL OCCURRENCE IN PREGNANCY

2018 ◽  
Author(s):  
М.Г. Николаева ◽  
А.П. Момот ◽  
Г.В. Сердюк ◽  
В.А. Елыкомов ◽  
К.А. Момот ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Gene Mutation ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Control Group ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Apc Resistance ◽  
Factor Va ◽  
And Control

Цель исследования: изучить связь феномена резистентности фактора Vа к активированному протеину С (АПС-резистентность) при носительстве мутации гена FVL (1691) GA с клинической реализацией во время беременности тромботических событий и гестационных осложнений, таких как преэклампсия, задержка развития плода и невынашивание беременности. Материалы и методы. Проведено проспективное клиническое когортное исследование 1100 беременных. Выделено 2 когорты: основная группа – 500 пациенток с генотипом FVL (1691) GA и группа контроля – 600 женщин с генотипом FVL (1691) GG. Результаты. Медиана нормализованного отношения (НО) АПС-резистентности в контрольной группе у беременных с генотипом FVL (1691) GG колебалась в диапазоне 1,0→0,86. У беременных – носителей генотипа FVL (1691) GA этот показатель был достоверно ниже – 0,55→0,48 (р < 0,05). У пациенток при НО > 0,5 течение беременности было благоприятным. Более выраженная АПС-резистентность (НО ≤ 0,49) ассоциировалась с гестационными осложнениями. Заключение. Полученные данные по АПС-резистентности позволяют относить в группу высокого риска по тромботическим и акушерским осложнениям женщин – носительниц мутации фактора V Лейден (1691) не только с генотипом АА, но и с генотипом GA. AПС-резистентность ≤ 0,49 (по показателю НО) при носительстве мутации фактора V Лейден (1691) GA может рассматриваться как прогностический маркер развития гестационных осложнений с наибольшей точностью при сроке 7-8 недель беременности. Aim: to study during pregnancy the relationship between factor Va resistance to activated protein C (APC-resistance) in carriers of FVL gene mutation (1691) GA with clinical realization of thrombotic events and gestational complications such as preeclampsia, fetal growth retardation and miscarriage. Materials and methods. A prospective clinical cohort study of 1100 pregnant women was performed. Two cohorts were identified: main group – 500 patients with FVL genotype (1691) GA and control group – 600 women with FVL genotype (1691) GG. Results. The median of normalized ratio (NR) of APC resistance in the control group with FVL genotype (1691) GG ranged from 1.0→0.86. In pregnant women – the carriers of FVL genotype (1691) GA this parameter was significantly lower – 0.55→0.48 (р < 0.05). In patients with HO > 0.5 the course of pregnancy was favorable. More expressed APS-resistance (НО ≤ 0,49) was associated with gestational complications. Conclusion. The obtained data on APC-resistance allow to classify women – the carriers of Factor V Leiden (1691) mutation, not only with the AA genotype but also with GA genotype as the group of high risk for thrombotic and obstetric complications. APC resistance ≤ 0.49 (according NR) with the carriage of Factor V Leiden mutation (1691) GA can be considered as a prognostic marker for the development of gestational complications with the greatest accuracy at a period of 7-8 weeks of gestation.

Evaluation of a New Assay Based on a FV-Dependent Prothrombinase Activator for the Detection of Activated Protein C Resistance Phenotype.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3994-3994
Author(s):  
Jogin Wu ◽  
Peter Quehenberger ◽  
Katherine Foltyn ◽  
Patricia Dillard
Keyword(s):  
Protein C ◽  
Tertiary Care ◽  
False Negative ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Reference Method ◽  
Coagulation Cascade ◽  
Factor V ◽  
Resistance Phenotype ◽  
Apc Resistance

Abstract Activated protein C (APC) resistance is the most frequent hereditary defect associated with deep venous thrombosis. Major cause of APC resistance phenotype is due to a point mutation of factor V (Factor V Leiden). A new clotting assay, Pefakit® APC-R Factor V Leiden (Pentapharm Ltd., Switzerland) for the detection of APC resistance phenotype was evaluated at two tertiary care hospitals, Duke University Medical Center, USA (Duke) and University of Vienna, Austria (Vienna). Samples of 242 subjects from Duke and 187 subjects from Vienna were included in the study among patients who were subjects for thormbophilia screening. The Pefakit® method is based on clotting time measurement triggered by a prothrombin activator added to a mixture of patient plasma diluted with factor V deficient plasma with and without APC. Robustness and specificity of the assay is enhanced by elimination of possible disturbing influence by factors upstream the coagulation cascade and heparin interference is precluded up to heparin level of 2 IU/ml by heparin inhibitor added to the regent. A similar, FDA approved commercial APC-R kit (COATEST of IL) was used for method comparison. Patients with elevated factor VIII (n=11), Coumadin (n=23), Lupus Anticoagulant (n-14), protein C deficient (n=7), protein S deficient (n=9), AT III (n=6) and women with pregnancy (n=9) were included in Duke study and no interference were found in phenotype. Using PCR/FRET DNA method as reference method the Pefakit® method provided 100 % sensitivity and 100 % specificity for the Vienna study and 99.0 % sensitivity and 98.6 % specificity for the Duke study and the COATEST provided 97.1 % specificity and 93.2 % sensitivity with the Duke study. Using two levels of genotype controls both studies showed similar intra and inter-assay precision (less than 6 % for the Vienna study and 9 % for the Duke study) as compared with the gold standard IL APC-R COATEST kit (less than 5 % CV). Of great interest one false positive sample from the Duke study is under investigation due to that the functional detection of the assay is supposed to detect other FV mutations leading to APC-R phenotype as well. Reasons that cause the other two false negative results for the Duke study are still unknown and under investigation. Both studies showed that the Pefakit® is simple and rebust assay. Both wild type and heterozygous groups have much higher ratio as compared with the reference method in differentiating them from homozygous phenotype. Figure Figure

A Reduced Sensitivity for Activated Protein C in the Absence of Factor V Leiden Increases the Risk of Venous Thrombosis

Blood ◽  
1999 ◽  
Vol 93 (4) ◽  
pp. 1271-1276 ◽  
Author(s):  
Marieke C.H. de Visser ◽  
Frits R. Rosendaal ◽  
Rogier M. Bertina
Keyword(s):  
Risk Factor ◽  
Confidence Interval ◽  
Venous Thrombosis ◽  
Protein C ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Apc Resistance ◽  
Increased Risk

Abstract Activated protein C (APC) resistance caused by the factor V Leiden mutation is associated with an increased risk of venous thrombosis. We investigated whether a reduced response to APC, not due to the factor V point mutation, is also a risk factor for venous thrombosis. For this analysis, we used the Leiden Thrombophilia Study (LETS), a case-control study for venous thrombosis including 474 patients with a first deep-vein thrombosis and 474 age- and sex-matched controls. All carriers of the factor V Leiden mutation were excluded. A dose-response relationship was observed between the sensitivity for APC and the risk of thrombosis: the lower the normalized APC sensitivity ratio, the higher the associated risk. The risk for the lowest quartile of normalized APC-SR (&lt;0.92), which included 16.5% of the healthy controls, compared with the highest quartile (normalized APC-SR &gt; 1.05) was greater than fourfold increased (OR = 4.4; 95% confidence interval, 2.9 to 6.6). We adjusted for VIII:C levels, which appeared to affect our APC resistance test. The adjusted (age, sex, FVIII:C) odds ratio for the lowest quartile was 2.5 (95% confidence interval, 1.5 to 4.2). So, after adjustment for factor VIII levels, a reduced response to APC remained a risk factor. Our results show that a reduced sensitivity for APC, not caused by the factor V Leiden mutation, is a risk factor for venous thrombosis.

Oral Contraceptive-Associated Thromboembolism. A Retrospective Analysis of Thrombophilic Work-out and Long Term Follow up in 57 Cases

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5348-5348
Author(s):  
Emmanouil Papadakis ◽  
Smaragda Efremidou ◽  
Haris Kartsios ◽  
Margarita Mpraimi ◽  
Kiriaki Kokoviadou ◽  
...  
Keyword(s):  
Family History ◽  
Protein C ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Apc Resistance ◽  
Increased Risk ◽  
Fv Leiden

Abstract Introduction: The increased risk of venous thrombosis in women taking oral contraceptives (OCs) has been recognized since the early 1960s. Coexistence of hereditary risk factors appears to have an additive effect. Women under OCs that carry the factor V Leiden mutation have a 35-fold increased risk of thromboembolic events compared to women without the mutation who are not on OCs. Evaluation of family and personal history is the mainstay of prophylaxis prior to OC administration, but often family thrombophilia or thromboembolic (TE) events are not reported prior to OCs prescription. Patients-Methods: Fifty-seven women with a median age of 28 (21–48) years, which suffered OC-associated TE, were studied. The median period of OC therapy prior to TE event was 2 months (0.5–60). Fifty-five of them experienced VTE while 2 suffered stroke. Leg thrombosis was the most common clinical finding [37/55 (67,2%) patients] Apart from personal and family history, Thrombophilia investigation included measurement of : serum Homocysteine, Antithrombin, Protein C and S, Lipoprotein (a), Activated Protein C (APC) resistance, antiphospholipid antibodies and lupus anticoagulant. In addition the presence of FV Leiden, FII 20210 GA mutations and MTHFR 677 CT polymorphism were determined. Results: A high prevalence of the factor V Leiden mutation was detected in the study group; 50% had APC-resistance test positive, 26 (45%) patients were found to be heterozygous and 3 (5,2%) homozygous for the FV Leiden mutation. Lp(a) elevation was observed in 19,3% and Homocysteine elevation in 15,8% of patients. In 9 women (15,8%) both family history and thrombophilic profile were negative. Serious VTE events (2 abdominal and 6 CNS thromboses) were observed only in the Leiden subgroup. During the follow up period ranging from months to 18 years, 3 women (6,25%) experienced a miscarriage and 14 suffered additional VTE events (25%) and they are currently on permanent anticoagulation. Conclusions : Universal thrombophilia screening of women prior to prescription of OCs is not advisable as it does not appear to be cost effective. However, screening certain subgroups, such as women with a known personal or family history, may be of great value. If a full thrombophilic profile can’t be performed, a mere activated protein C resistance test, that reflects the presence of the factor V Leiden mutation, may provide an easy and cheap way of identifying and consulting properly women at higher risk for VTE prior to OC use. Women with OC-associated VTE and thrombophilia carry a substantial recurrence risk that persists for years.

Low cut-off values increase diagnostic performance of protein S assays

2010 ◽  
Vol 104 (09) ◽  
pp. 618-625 ◽  
Author(s):  
Min Ki ten Kate ◽  
Hanneke Kluin-Nelemans ◽  
André Mulder ◽  
René Mulder
Keyword(s):  
Healthy Volunteers ◽  
Diagnostic Performance ◽  
Factor V Leiden ◽  
Protein S ◽  
Study Groups ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Heterozygous Carriers ◽  
Lower Cutoff ◽  
Cutoff Levels

SummaryConflicting data have been reported on the accuracy of protein S (PS) assays for detection of hereditary PS deficiency. In this study we assessed the diagnostic performance of two total PS antigen assays, four free PS assays and three PS activity assays in a group of 28 heterozygous carriers of mutations in PROS1 and 165 control subjects. Several control groups were formed, one of healthy volunteers and – because PS levels are influenced by oral contraception and pregnancy, and assays measuring PS activity may be influenced by the presence of the factor V Leiden mutation -, we also investigated the influences of these factors. All nine PS assays detected significantly reduced PS levels in subjects with a PROS1 mutation. Eight out of nine PS assays showed a 100% sensitivity and 100% specificity to detect heterozygous carriers of mutations in PROS1 with values far below the lower limit of the reference values obtained from healthy volunteers. Low specificities were found in subjects with a factor V Leiden mutation and in pregnant women. At lower cutoff levels, equal to the highest PS value found in heterozygous carriers of mutations in PROS1, the specificity considerably increased in these subjects. When using low cut-off levels equal to the highest PS value found in heterozygous carriers of mutations in PROS1, ensuring 100% sensitivity, the specificity in all study groups increases considerably, by which misclassification can be maximally avoided.

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