The frequency of congenital AT deficiency was significantly higher in subjects with pregnancy-related and idiopathic VTE than in those with VTE due to other causes, and congenital PC and PS deficiency were frequently associated with idiopathic VTE.
Sequence analysis revealed Thr-315 is a consensus N-linked glycosylation site for Asn-313 and that its elimination significantly (∼four- to fivefold) improves the maximum velocity of PC activation by the thrombin-TM complex, explaining the basis for the proband's negative VTE pedigree.
We performed targeted gene sequencing of the PC gene (PROC) and EPCR genes (PROCR) in patients with unprovoked venous thromboembolism (VTE) to determine whether mutations that impair PC-EPCR interactions are associated with an increased risk of VTE.
In the Chinese population, PS and PC deficiencies are common thrombophilia for VTE during pregnancy and thrombophilia screening should be recommended in all pregnant women who suffer from VTE.
Considering the increased risks with the association between VTE and the higher prevalence of PC and PS deficiencies, TT genotype mutations and high level of fibrinogen, it is advisable to perform a complete thrombophilia screening in TS patients before starting HRT.
The most accepted inherited hemostatic abnormalities associated with venous thromboembolism are factor V Leiden (FVL) and factor II (FII) G20210A mutations, as well as deficiencies in antithrombin (AT), protein C (PC), and protein S (PS).
The role of the A3 haplotype and soluble endothelial protein C receptor (sEPCR) plasma levels in predisposing the carriers of two peculiar dysfunctional protein C (PC) variants (PC Arg-1-->Cys and PC Arg-1-->Leu, also known as PC Padua(2) and PC Padua(3), respectively) to venous thromboembolism (VTE) has been evaluated.
In order to assess whether the HR2 haplotype of the factor V gene (HR2) increases the risk of venous thromboembolism (VTE) in carriers of antithrombin (AT), protein C (PC) or S (PS) defects, we performed this determination in 336 subjects, who were family members of 66 symptomatic patients with clotting inhibitors defects.
The risk of spontaneous or risk-period related venous thromboembolism in family members of symptomatic carriers of antithrombin (AT), protein C (PC) or protein S (PS) defects, as well as of the Factor V Leiden mutation is still undefined.
It is remarkable that certain patients with heterozygous protein C (PC) deficiency manifest venous thromboembolism (VTE), whereas others, particularly those belonging to families with homozygous PC deficiency, remain asymptomatic.
The incidence of these hereditary disorders in our 204 patients (106 males and 98 females) with venous thromboembolism were 4% (three cases deficient in PC, three in PS, two in PLG, and one patient in AT III).Their families were studied.