Spontaneous venous thrombosis in a young patient with combined factor V Leiden and lupus anticoagulant

Coagulation factor V gene 1691G>A polymorphism as an indicator for risk and prognosis of lower extremity deep venous thrombosis in Chinese Han population

The purpose of this study was to explore the negative influence coagulation factor V (FV) 1691G>A polymorphism had on the risk and prognosis of lower extremity deep venous thrombosis (LDVT) in Chinese Han population.A total of 348 patients with LDVT (LDVT group) and 398 healthy individuals (control group) were selected to further this study. A polymerase chain reaction-restriction fragment length polymorphism method was used to analyze the FV gene 1691G>A polymorphism; coagulation and anticoagulation indexes of patients with LDVT were detected as a result. A 3-year follow-up and logistic regression analysis were conducted to determine the corresponding correlations between FV gene and LDVT.In comparison with the control group, the frequencies of GA and AA genotypes and A allele of 1691G>A polymorphism significantly increased in the LDVT group. Also, in comparison with patients with LDVT carrying GG genotype of FV gene 1691G>A polymorphism, the following activities reduced significantly: prothrombin time, activated partial thromboplastin time, fibrinogen, protein C, and protein S, while activated protein C resistance and lupus anticoagulant positive rate increased in patients carrying A allele (GA + AA). Logistic regression analysis indicated that FV gene 1691G>A polymorphism, total cholesterol, low-density lipoprotein cholesterol, and LDVT family histories were all closely related with LDVT and were subsequent independent risk factors for LDVT. Moreover, patients with LDVT carrying A allele (GA + AA) had both higher patency and recurrence rates than those carrying GG genotype.FV gene 1691G>A polymorphism may be associated with both the risk and prognosis of LDVT, potentially being a useful index for monitoring LDVT prognosis and risk.

Hyperhomocysteinemia Relates to the Subtype of Antiphospholipid Antibodies in Non-SLE Patients

Abnormal increases of antiphospholipid antibody and plasma homocysteine levels are recently emerging as nonlipidic risk factors for cerebral atherogenesis and thrombosis. Both antiphospholipid antibody and homocysteine share many similar bioeffects in hemostasis, but their interaction is still inconsistent. In this study, we examined the relation between the plasma homocysteine level and lupus anticoagulant, anticardiolipin antibody, and anti-β2-glycoprotein I antibody in patients with noncardiac cerebral ischemia. Systemic lupus erythrematosus patients were excluded. The results showed a higher frequency of moderate hyperhomocysteinemia in patients with an abnormal increase of lupus anticoagulant only. Neither the serum folate and cobalamin levels nor methylenetetrahydrofolate reductase allele mutation contributes to this result. Accordingly, homocysteine interacts with lupus anticoagulant to promote cerebral atherosclerosis and ischemia. The role of vasculopathic or prothrombotic autoantibody generation in response to specific pathological change such as hyperhomocysteinemia warrants further investigation.