R255h Amino acid substitution of protein Z identified in patients with factor V Leiden mutation

SummaryA protein Z deficiency is presumably related with a threefold risk of venous and arterial thrombosis. Mucosal bleedings and post-operative haematomas can occur more frequently. This is seen in an increased in vivo bleeding time without other plasmatic coagulation disorders or thrombopathies. Pregnancy complications, especially abortions before the 15th week of gestation, are described as well. Patients, methods: Since May 2011 the plasmatic concentration of protein Z has been tested in 684 patients of the Hämostaseologicum. Results: In 74 patients a protein Z deficiency has been found. In other 45 patients protein Z was reduced because of the intake of phenprocoumon or coumadin. Of the 74 patients with diminished protein Z concentration 39 were marginally decreased (protein Z 1000–1500 μg/l). Of the 35 patients with a protein Z concentration <1000 μg/l 12 had had a thrombosis before (6 strokes, 3 DVT or PE, 1 arterial thrombosis, 1 retinal branch vein occlusion, 1 acute hearing loss). 7 had arterial hypertension, 2 suffered from diabetes mellitus. Of the patients who had a thrombosis 6 had a heterozygous factor V Leiden mutation. 10 had a microcirculation disorder (Raynaud’s phenomenon), 4 had had bleeding complications before, 3 had a von Willebrand disease type I, 6 patients had had abortions and 4 were healthy. Of the 39 patients with protein Z concentrations between 1000 and 1500 μg/l 18 had experienced a thrombosis before (9 DVT or PE, 3 myocardial infarctions, 1 CHD, 3 strokes, 1 retinal branch vein occlusion, 1 PAOD I, 1 tinnitus). 5 additionally had arterial hypertension. 13 suffered from Raynaud’s phenomenon, of which 7 had a hypotension. Of the patients with thromboses 3 had a heterozygous factor V Leiden mutation and one a protein C deficiency. 7 patients had had an abortion before. Bleeding complications were seen in 4 patients, of which 3 suffered from von Willebrand disease type 1.

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Protein Z, a protein seeking a pathology

Thrombosis and Haemostasis ◽

10.1160/th08-01-0024 ◽

2008 ◽

Vol 100 (10) ◽

pp. 548-556 ◽

Cited By ~ 26

Author(s):

Marc Vasse

Keyword(s):

Risk Factor ◽

Vitamin K ◽

Factor V Leiden ◽

Factor Vii ◽

Factor V ◽

Factor X ◽

Protein Z ◽

Factor V Leiden Mutation ◽

Thrombotic Risk ◽

G20210a Mutation

SummaryProtein Z (PZ) is a vitamin K-dependent factor identified in human plasma in 1984 characterized by an homology with other vitamin K-dependent factors (factor VII, IX, X, protein C). In contrast to these factors, PZ does not possess any enzymatic activity but is involved as a cofactor in the down-regulation of coagulation by forming a complex with the protein Z-dependent protease inhibitor (ZPI). ZPI inhibits the activated factor X (FXa) on phospholipid surface. In mice, the disruption of PZ gene is asymptomatic, but the association with the factor V Leiden mutation leads to a quasi complete mortality during the neonatal period with microvascular thrombosis. In humans, PZ is characterized by an unusual wide distribution in plasma, and a major decrease induced by warfarin. Isolated PZ deficiency does not seem to constitute a risk for venous thrombosis, but a severe PZ deficiency could increase the risk of well recognized venous thrombotic risk factors such as factor V Leiden, G20210A mutation or hyperhomocysteinemia. Unexpectedly, a relationship between PZ deficiency and ischemic arterial diseases such as stroke, acute coronary syndromes or peripheral arterial disease was described but not confirmed by all studies. PZ deficiency could be also a risk factor for early fetal losses, and increases the arterial risk in antiphospholipid syndrome. This review analyzes the different studies so far published and discusses the various results obtained in order to understand whether or not protein Z deficiency could be considered as an arterial ischemic risk factor.

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Thrombophilia and risk of VTE recurrence according to the age at the time of first VTE manifestation

VASA ◽

10.1024/0301-1526/a000447 ◽

2015 ◽

Vol 44 (4) ◽

pp. 313-323 ◽

Cited By ~ 6

Author(s):

Lea Weingarz ◽

Marc Schindewolf ◽

Jan Schwonberg ◽

Carola Hecking ◽

Zsuzsanna Wolf ◽

...

Keyword(s):

Factor V Leiden ◽

Cox Proportional Hazards ◽

First Episode ◽

Factor V ◽

Factor V Leiden Mutation ◽

Younger Patients ◽

Risk Of Recurrence ◽

G20210a Mutation ◽

Increased Risk ◽

The Impact

Abstract. Background: Whether screening for thrombophilia is useful for patients after a first episode of venous thromboembolism (VTE) is a controversial issue. However, the impact of thrombophilia on the risk of recurrence may vary depending on the patient’s age at the time of the first VTE. Patients and methods: Of 1221 VTE patients (42 % males) registered in the MAISTHRO (MAin-ISar-THROmbosis) registry, 261 experienced VTE recurrence during a 5-year follow-up after the discontinuation of anticoagulant therapy. Results: Thrombophilia was more common among patients with VTE recurrence than those without (58.6 % vs. 50.3 %; p = 0.017). Stratifying patients by the age at the time of their initial VTE, Cox proportional hazards analyses adjusted for age, sex and the presence or absence of established risk factors revealed a heterozygous prothrombin (PT) G20210A mutation (hazard ratio (HR) 2.65; 95 %-confidence interval (CI) 1.71 - 4.12; p < 0.001), homozygosity/double heterozygosity for the factor V Leiden and/or PT mutation (HR 2.35; 95 %-CI 1.09 - 5.07, p = 0.030), and an antithrombin deficiency (HR 2.12; 95 %-CI 1.12 - 4.10; p = 0.021) to predict recurrent VTE in patients aged 40 years or older, whereas lupus anticoagulants (HR 3.05; 95%-CI 1.40 - 6.66; p = 0.005) increased the risk of recurrence in younger patients. Subgroup analyses revealed an increased risk of recurrence for a heterozygous factor V Leiden mutation only in young females without hormonal treatment whereas the predictive value of a heterozygous PT mutation was restricted to males over the age of 40 years. Conclusions: Our data do not support a preference of younger patients for thrombophilia testing after a first venous thromboembolic event.

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Coagulation Factor V Leiden Mutation Was Detected in the Patients with Activated Protein C Resistance in Thailand

Thrombosis and Haemostasis ◽

10.1055/s-0037-1615201 ◽

1998 ◽

Vol 80 (08) ◽

pp. 344-345 ◽

Cited By ~ 2

Author(s):

Pasra Arnutti ◽

Motofumi Hiyoshi ◽

Wichai Prayoonwiwat ◽

Oytip Nathalang ◽

Chamaiporn Suwanasophon ◽

...

Keyword(s):

Protein C ◽

Activated Protein C ◽

Factor V Leiden ◽

Coagulation Factor ◽

Factor V ◽

Activated Protein C Resistance ◽

Factor V Leiden Mutation ◽

Coagulation Factor V

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High Frequency of Factor V Leiden Mutation and Prothrombin 20210A Variant in Romanies of Eastern Hungary

Thrombosis and Haemostasis ◽

10.1055/s-0037-1614872 ◽

1999 ◽

Vol 82 (11) ◽

pp. 1555-1556 ◽

Cited By ~ 5

Author(s):

R. Póka ◽

G. Losonczy ◽

L. Muszbek ◽

I. Balogh

Keyword(s):

High Frequency ◽

Factor V Leiden ◽

Factor V ◽

Factor V Leiden Mutation ◽

Prothrombin 20210A

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Low Prevalence of the Factor V Leiden Mutation Among “Severe” Hemophiliacs with a “Milder” Bleeding Diathesis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649922 ◽

1995 ◽

Vol 74 (05) ◽

pp. 1255-1258 ◽

Cited By ~ 50

Author(s):

Arnaldo A Arbini ◽

Pier Mannuccio Mannucci ◽

Kenneth A Bauer

Keyword(s):

Hemophilia A ◽

Factor V Leiden ◽

Protein S ◽

Factor Ix ◽

Hemophilia B ◽

Factor V ◽

Bleeding Diathesis ◽

Mutation Site ◽

Spontaneous Bleeding ◽

Factor V Leiden Mutation

SummaryPatients with hemophilia A and B and factor levels less than 1 percent of normal bleed frequently with an average number of spontaneous bleeding episodes of 20–30 or more. However there are patients with equally low levels of factor VIII or factor IX who bleed once or twice per year or not at all. To examine whether the presence of a hereditary defect predisposing to hypercoagulability might play a role in amelio rating the hemorrhagic tendency in these so-called “mild severe” hemophiliacs, we determined the prevalence of prothrombotic defects in 17 patients with hemophilia A and four patients with hemophilia B selected from 295 and 76 individuals with these disorders, respectively, followed at a large Italian hemophilia center. We tested for the presence of the Factor V Leiden mutation by PCR-amplifying a fragment of the factor V gene which contains the mutation site and then digesting the product with the restriction enzyme Mnll. None of the patients with hemophilia A and only one patient with hemophilia B was heterozygous for Factor V Leiden. None of the 21 patients had hereditary deficiencies of antithrombin III, protein C, or protein S. Our results indicate that the milder bleeding diathesis that is occasionally seen among Italian hemophiliacs with factor levels that are less than 1 percent cannot be explained by the concomitant expression of a known prothrombotic defect.

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Detection of the Factor V Leiden Mutation Using Whole Blood PCR

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650309 ◽

1996 ◽

Vol 75 (03) ◽

pp. 520-521 ◽

Cited By ~ 8

Author(s):

D C Rees ◽

M Cox ◽

J B Clegg

Keyword(s):

Whole Blood ◽

Factor V Leiden ◽

Factor V ◽

Factor V Leiden Mutation

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“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

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650290 ◽

1996 ◽

Vol 75 (03) ◽

pp. 422-426 ◽

Cited By ~ 53

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.

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