Influence of decreased fibrinolytic activity and plasminogen activator inhibitor-1 4G/5G polymorphism on the risk of venous thrombosis.

: Objective of our study is to determine whether decreased fibrinolytic activity or plasminogen activator inhibitor (PAI)-1 4G/5G polymorphism influence the risk of venous thrombosis.Our case-control study included 100 patients with venous thrombosis, and 100 random controls. When patients were compared with random controls, unconditional logistic regression was used to calculate odds ratios (ORs) with 95% confidence intervals (CIs).Decreased fibrinolytic activity yielded a 2.7-fold increase in risk for venous thrombosis than physiological fibrinolytic activity (OR 2.70; 95% CI 1.22-5.98), when comparing patients with random controls. Adjustment for several putative confounders did not change the estimate (OR 3.02; 95% CI 1.26-7.22). Analysis of venous thrombotic risk influenced by PAI-1 genotype, showed no influence of PAI-1 4G/5G gene variant in comparison with 5G/5G genotype (OR 0.57 95% CI; 0.27-1.20).Decreased fibrinolytic activity increased, whereas PAI-1 4G/5G polymorphism did not influence venous thrombosis risk in this study.

Are Prothrombotic Mutations a Time-to-Event Risk Factor?

BACKGROUND: Deep vein thrombosis (DVT) represents a common disorder involving genetic and acquired risk factors. It has been proposed that acquired risk factors are more important with aging than genetic factors, indicating different prevalence of prothrombotic mutations throughout the lifespan. OBJECTIVE: To determine the role of the most frequent prothrombotic genetic risk factors (Factor V [FV] Leiden and Factor II [FII] G20210A mutations) in first-time DVT etiology in patients of different ages. METHOD: This retrospective study included 701 patients living in Serbia with diagnosed DVT as a first-time thrombotic event. RESULTS: Risk assessment for mutations as age-related markers showed no statistical difference (FV Leiden mutation-OR, 1.027; 95% confidence interval [CI], .87-1.22; P = .76 and FII G20210A mutation-OR, 0.940, 95% CI, .74-1.19; P = .61). Our results show similar mutation prevalence regardless of how old the patients were at the time of the first DVT occurrence. CONCLUSION: Our results indicate that these 2 mutations cannot be used as prognostic marker for time-to-event first DVT in the Serbian population; however, further studies are required.

Thrombin generation, D-dimer and protein S in uncomplicated pregnancy.

BACKGROUND: Gestational age-specific reference values are essential for the accurate interpretation of haemostatic tests during pregnancy. METHODS: Our 1-year prospective study included 40 healthy pregnant women with a median age of 30 (range 22-40) years; the subjects were followed in order to establish the gestational age dependent values for endogenous thrombin potential (ETP), D-dimer and protein S (activity and free). RESULTS: During the first trimester 50% of studied women had ETP >100% (reference values out of pregnancy); in the second trimester an ETP over 100% was observed in all women; ETP values remained unchanged during the third trimester. In the first trimester, the median D-dimer concentration of 0.30 mg/L, in the second 0.91 mg/L and in the third of 1.45 mg/L were observed. During the first trimester 14/40 subjects had protein S activity below reference range (<59%, out of pregnancy); the median value of 61.35; interquartile range (IQR) 20.38; in the second 21/37; the median value of 53.1 (IQR 15.65); in the third trimester 28/37 had low level of protein S activity with the median value of 49.0 (IQR 18.8). Free protein S showed a slight decrease from the first trimester; it remained almost stable during the rest of pregnancy, with the equal number of pregnant women with reduced free protein S. CONCLUSIONS: Related to the gestational age, a significant increase of ETP and D-dimer, from the second trimester was observed; the decrease of protein S was observed already from the early pregnancy, with more pronounced variability of protein S activity.

Risk factors for thrombosis in Serbian children.

Venous and arterial thromboses are increasingly encountered in the pediatric population. We present results of a case-control study of inherited and acquired risk factors for thrombosis in 129 pediatric patients from the first day of life to 18 years. The aims of study were to determine the importance of thrombophilic risk factors and comorbidity as a cause of thrombosis in children. Single thrombophilic risk factor was found in 24.4% (n = 21), whereas combined thrombophilic factors were found in 15.1% (n = 13) patients. A total of 87.2% of the children had recognized thrombophilic risk factors for thrombosis and/or additional comorbid risk factors. The single independent risk factors for thrombosis were mutation of factor V Leiden (P = 0.021), lupus anticoagulant antibodies (P = 0.028), and comorbidity (P = 0.000). Mutation of factor V Leiden [odds ratio (OR), 6.2 (95% confidence interval, CI 1.1-38.1, P = 0.048] was found to be a risk factor for venous thrombosis. Lupus anticoagulant antibodies were related to both venous (P = 0.008) and arterial thrombosis (P = 0.016). The frequency of inherited thrombophilic factors were the same in neonates and adolescents (23%). The prothrombotic gene mutations were present in 18.6% (n = 8) of asymptomatic children. Our study confirms that thrombosis in children is a multifactorial disorder, and associated most with the underlying medical disease (comorbidity) for vein thrombosis [OR, 18.6 (95% CI 3.7-93.4), P = 0.000] and for arterial thrombosis [OR, 10.5 (95% CI 2.2-49.9) P = 0.003]. Inherited thrombophilic disorders contributed to the development of thrombosis in children.