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1.
Transl Res ; 215: 41-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31525325

RESUMO

A prothrombotic state is frequently observed in patients with cancer and contributes to the risks of venous thromboembolism (VTE), arterial thromboembolism (ATE), tumor progression, and death. Altered ex vivo properties of plasma clot formation and lysis have been observed in patients with cancer. The aim of this prospective study was to comprehensively characterize the relationship between plasma clot properties, inflammation, hypercoagulability, thrombotic complications, and mortality in patients with cancer using a tissue-factor-based turbidimetric assay of clot formation and lysis. Turbidity parameters were determined in 815 patients with newly-diagnosed or recurrent cancer and 97 healthy controls. Patients were followed-up for 2 years and rates of VTE (n = 72 events), ATE (n = 21 events), and death (n = 304 events) were assessed. Compared to controls, cancer patients' turbidity profiles showed an increased clot formation potential and higher resistance toward fibrinolysis. Elevated biomarkers of inflammation and hemostasis, such as C-reactive protein, FVIII, and thrombin generation explained substantial amounts of variation in turbidity parameters. In a prospective analysis, altered parameters of clot formation identified cancer patients at high risk of ATE (Hazard ratio [HR] per doubling of peak absorbance: 4.43, 95% CI: 1.50-13.07, P = 0.007) and death (HR per doubling of peak absorbance: 2.73, 2.00-3.72, P< 0.0001); these findings were independent of other prognostic covariates. Contrarily, turbidity parameters were not associated with risk of VTE (HR per doubling of peak absorbance: 1.15, 0.66-2.01, P = 0.62). We conclude that patients with cancer have altered ex vivo properties of clot formation which predict risks of ATE and mortality but not VTE.

2.
J Thromb Haemost ; 17(9): 1478-1488, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31177606

RESUMO

BACKGROUND: In a large proportion of patients with a mild to moderate bleeding tendency no diagnosis can be established (bleeding of unknown cause, BUC). OBJECTIVES: To investigate possible dysfunctions in thrombin generation and plasma clot formation and lysis in patients with BUC from the Vienna Bleeding Biobank (VIBB). PATIENTS AND METHODS: Thrombin generation and plasma clot properties of 382 BUC patients were compared to those of 100 healthy controls and 16 patients with factor VIII (FVIII) activity ≤50%. RESULTS: Thrombin generation was significantly impaired in BUC patients compared to healthy controls, exhibiting a prolonged lag time and time to peak and decreased maximum thrombin generation, velocity index, and area under the curve (AUC). The assessment of clot formation and lysis in BUC patients revealed a lower clot formation rate (Vmax), resulting in a longer TTP, increased absorbance (ΔAbs), and a shorter clot lysis time (CLT) than in healthy controls. Comparing patients with FVIII activity ≤ 50% to those with BUC, parameters of thrombin generation and clot formation and lysis were either stronger or comparably impaired. Bleeding severity did not correlate with parameters of thrombin generation, clot formation, or clot lysis. CONCLUSION: Patients with BUC have an impaired hemostatic capacity reflected by a lower thrombin-generation potential, a lower clot formation rate, increased clot turbidity, and shorter clot lysis time, which might contribute to their increased bleeding tendency. Assays monitoring these parameters can alert physicians of hemostatic impairment and should be considered in situations where traditional hemostatic lab tests fail to reveal the clinical bleeding tendency.

3.
Blood ; 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064749

RESUMO

A targeted high-throughput sequencing (HTS) panel test for clinical diagnostics requires careful consideration of the inclusion of appropriate diagnostic-grade genes, the ability to detect multiple types of genomic variation with high levels of analytic sensitivity and reproducibility, and variant interpretation by a multi-disciplinary team (MDT) in the context of the clinical phenotype. We have sequenced 2,396 index patients using the ThromboGenomics HTS panel test of diagnostic-grade genes known to harbour variants associated with rare bleeding, thrombotic or platelet disorders (BTPD). The molecular diagnostic rate was determined by the clinical phenotype, with an overall rate of 49.2% for all thrombotic, coagulation, platelet count and function disorder patients and a rate of 3.2% for patients with unexplained bleeding disorders characterized by normal hemostasis test results. The MDT classified 745 unique variants, including copy number and intronic variants, as Pathogenic, Likely Pathogenic or Variants of Uncertain Significance. Half (50.9%) of these variants are novel and 41 unique variants were identified in 7 genes recently found to be implicated in BTPD. Inspection of canonical hemostasis pathways identified 29 patients with evidence of oligogenic inheritance. A molecular diagnosis has been reported for 894 index patients providing evidence that introducing an HTS genetic test is a valuable addition to laboratory diagnostics in patients with a high likelihood of having an inherited BTPD.

4.
Blood Adv ; 3(5): 769-776, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30837214

RESUMO

Lupus anticoagulant (LA) has been associated with pregnancy complications and pregnancy loss. Identification of predictive factors could aid in deciding on therapeutic management. To identify risk factors for adverse pregnancy outcomes in high-risk women with persistently positive LA, we prospectively followed 82 women of childbearing age, of whom 23 had 40 pregnancies within the Vienna Lupus Anticoagulant and Thrombosis Study. Pregnancy complications occurred in 28/40 (70%) pregnancies, including 22 (55%) spontaneous abortions (<10th week of gestation [WOG]: n = 12, 10th to 24th WOG: n = 10) and 6 deliveries <34th WOG (15%, 3 due to severe preeclampsia/HELLP [hemolysis, elevated liver enzymes, and a low platelet count] syndrome, 3 due to placental insufficiency). One abortion was followed by catastrophic antiphospholipid syndrome. Neither a history of pregnancy complications nor of thrombosis, or prepregnancy antiphospholipid antibody levels were associated with adverse pregnancy outcomes. In logistic regression analysis, higher age was associated with a lower risk of adverse pregnancy outcome (per 5 years' increase: odds ratio [OR] = 0.41, 95% confidence interval [CI]: 0.19-0.87), a high Rosner index (index of circulating anticoagulant) predicted an increased risk (OR = 4.51, 95% CI: 1.08-18.93). Live birth rate was 15/28 (54%) in women on the combination of low-molecular-weight heparin and low-dose aspirin and 3/12 (25%) in those with no treatment or a single agent. We conclude that the risk of severe, even life-threatening pregnancy complications and adverse pregnancy outcomes is very high in women with persistent LA. A high Rosner index indicates an increased risk. Improved treatment options for women with persistently positive LA are urgently needed.

5.
Ann Hematol ; 2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30467688

RESUMO

Lupus anticoagulants (LA) are a heterogeneous group of antiphospholipid antibodies (aPLAs) that promote thrombosis. Tissue factor (TF)-bearing extracellular vesicles (EVs) might contribute to the prothrombotic state of patients with persistent LA and a history of thrombosis. To investigate if EV-associated TF activity is elevated in a well-defined group of LA-positive patients with a history of thrombosis in comparison to that of healthy controls. Adult patients (n = 94, median age 40.1 years, interquartile range (IQR) 29.9-53.4; 87% females) positive for LA and a history of thrombosis (78% venous thrombosis, 17% arterial thrombosis, 5% venous thrombosis and arterial thrombosis) and healthy age- and sex-matched controls (n = 30, median age 42.9 years, IQR 38.6-45.8, 77% females) were included in this study. EV-TF activity was determined with a factor Xa generation assay and anti-ß2-glycoprotein (anti-ß2GPI) and anticardiolipin (aCL) antibodies by enzyme-linked immunoassays. EV-TF activity did not differ between 94 LA-positive patients with a history of thrombosis (median 0.05 pg/mL, IQR 0.00-0.14) and 30 healthy controls (median 0.06, IQR 0.00-0.11, p = 0.7745). No correlation was found between EV-TF activity and lupus-sensitive activated partial thromboplastin time (aPTT-LA) (rho = 0.034), Rosner index (rho = - 0.056), anti-ß2GPI IgG (rho = 0.05), anti-ß2GPI IgM (rho = - 0.08), aCL IgG (rho = 0.12), and aCL IgM (rho = - 0.11) in LA-positive patients. We found low EV-TF activity levels in LA-positive patients and a history of thrombosis and no correlation with analyzed aPLAs. Our data indicate that circulating TF-bearing EVs do not contribute to the prothrombotic state of patients with LA.

6.
BMC Med ; 15(1): 54, 2017 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-28279213

RESUMO

BACKGROUND: Patients with the lupus anticoagulant (LA) are at an increased risk of thrombotic events, which in turn increase the risk of death. Understanding the determinants of thrombotic risk in patients with LA may pave the way towards targeted thromboprophylaxis. In the Vienna Lupus Anticoagulant and Thrombosis Study (LATS), we systematically evaluate risk factors for thrombotic events in patients with LA. METHODS: We followed 150 patients (mean age: 41.3 years, female gender: n = 122 (81.3%), history of thrombosis or pregnancy complications: n = 111 (74.0%)), who tested repeatedly positive for LA until development of thrombosis, death, or censoring. The primary endpoint was a composite of arterial or venous thrombotic events (TEs). RESULTS: During a median follow-up of 9.5 years (range: 12 days-13.6 years) and 1076 person-years, 32 TEs occurred (arterial: n = 16, venous: n = 16; cumulative 10-year TE incidence: 24.3%). A prolonged lupus-sensitive activated partial thromboplastin time (aPTT-LA) (adjusted subdistribution hazard ratio (SHR) = 2.31, 95% CI: 1.07--5.02), diabetes (adjusted SHR = 4.39, 95% CI: 1.42-13.57), and active smoking (adjusted SHR = 2.31, 95% CI: 1.14-5.02) emerged as independent risk factors of both arterial and venous thrombotic risk. A risk model that includes a prolonged lupus-sensitive aPTT, smoking, and diabetes enabled stratification of LA patients into subgroups with a low, intermediate, and high risk of thrombosis (5-year TE risk of 9.7% (n = 77), 30.9% (n = 51), and 56.8% (n = 22). CONCLUSIONS: Long-term thrombotic risk in patients with LA is clustered within subjects harboring typical cardiovascular risk factors in addition to a prolonged lupus-sensitive aPTT, whereas patients with none of these risk factors represent a large subgroup with a low risk of thrombosis.


Assuntos
Inibidor de Coagulação do Lúpus/efeitos adversos , Trombose/epidemiologia , Trombose/etiologia , Adulto , Doenças Cardiovasculares/complicações , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
7.
Ann Hematol ; 96(3): 489-495, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28018998

RESUMO

In more than 50% of patients with a mild-to-moderate bleeding tendency, no underlying cause can be identified (bleeding of unknown cause, BUC). Data on parameters of fibrinolysis in BUC are scarce in the literature and reveal discrepant results. It was the aim of this study to investigate increased fibrinolysis as a possible mechanism of BUC. We included 270 patients (227 females, median age 44 years, 25-75th percentile 32-58) with BUC and 98 healthy controls (65 females, median age 47 years, 25-75thpercentile 39-55). Tissue plasminogen activator (tPA-) antigen and activity, plasminogen activator inhibitor type-1 (PAI-1), tPA-PAI-1 complexes, thrombin activatable fibrinolysis inhibitor (TAFI), α2-antiplasmin, and D-dimer were determined. While PAI-1 deficiency was equally frequent in patients with BUC and controls (91/270, 34%, and 33/98, 34%, p = 0.996), tPA activity levels were more often above the detection limit in patients than in controls (103/213, 48%, and 23/98, 23%, p < 0.0001). We found lower levels of tPA-PAI-1 complexes (6.86 (3.99-10.00) and 9.11 (7.17-13.12), p < 0.001) and higher activity of TAFI (18.61 (15.80-22.58) and 17.03 (14.02-20.02), p < 0.001) and α2-antiplasmin (102 (94-109) and 98 (90-106], p = 0.003) in patients compared to controls. Detectable tPA activity (OR 3.02, 95%CI 1.75-5.23, p < 0.0001), higher levels of TAFI (OR 2.57, 95%CI 1.48-4.46, p = 0.0008) and α2-antiplasmin (OR 1.03, 95%CI 1.01-1.05, p = 0.011), and lower levels of tPA-PAI-1 complexes (OR 0.90, 95%CI 0.86-0.95, p < 0.0001) were independently associated with BUC in sex-adjusted logistic regression analyses. We conclude that the fibrinolytic system can play an etiological role for bleeding in patients with BUC.


Assuntos
Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/diagnóstico , Fibrinólise/fisiologia , Hemorragia/sangue , Hemorragia/diagnóstico , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Blood ; 125(22): 3477-83, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25810488

RESUMO

Data on the clinical course of lupus anticoagulant (LA)-positive individuals with or without thrombotic manifestations or pregnancy complications are limited. To investigate mortality rates and factors that might influence mortality, we conducted a prospective observational study of LA-positive individuals. In total, 151 patients (82% female) were followed for a median of 8.2 years; 30 of the patients (20%) developed 32 thromboembolic events (15 arterial and 17 venous events) and 20 patients (13%) died. In univariable analysis, new onset of thrombosis (hazard ratio [HR] = 8.76; 95% confidence interval [CI], 3.46-22.16) was associated with adverse survival. Thrombosis remained a strong adverse prognostic factor after multivariable adjustment for age and hypertension (HR = 5.95; 95% CI, 2.43-14.95). Concomitant autoimmune diseases, anticoagulant treatment at baseline, or positivity for anticardiolipin- or anti-ß2-glycoprotein I antibodies were not associated with mortality. In a relative survival analysis, our cohort of LA positives showed a persistently worse survival in comparison with an age-, sex-, and study-inclusion-year-matched Austrian reference population. The cumulative relative survival was 95.0% (95% CI, 88.5-98.8) after 5 years and 87.7% (95% CI, 76.3-95.6) after 10 years. We conclude that occurrence of a thrombotic event is associated with higher mortality in patients with LA. Consequently, the prevention of thromboembolic events in LA positives might improve survival.


Assuntos
Síndrome Antifosfolipídica/mortalidade , Inibidor de Coagulação do Lúpus/sangue , Trombose/mortalidade , Adulto , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/complicações , Áustria/epidemiologia , Estudos de Casos e Controles , Causas de Morte , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/epidemiologia , Análise de Sobrevida , Trombose/sangue , Trombose/complicações
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