RESUMEN
The study was aimed to investigate the factor V coagulation activity (FV:C), and to evaluate FVgene polymorphisms and activated protein C resistance (APCR) in the patients with venous thromboembolism (VTE). 95 patients with VTE and 95 normal controls were investigated for FV gene polymorphisms. FV Leiden, FVCambridge, and FVHong Kong were detected by PCR, MnlI and BstNI digestion respectively. FVAsp79His and FVI359T were detected by MassARRAY. FV:C and APCR in 65 patients with VTE and 60 normal controls were determined by a one-stage clotting method and the APTT-based assays respectively. The results showed that the mean levels of plasma FV:C were significantly higher in VTE group than that in controls (108.03% +/- 28.29% vs 95.17% +/- 29.75%) (P = 0.008), the incidence of APCR were 20.0% (13 of 65 cases) in patients with VTE and 5.0% (3 of 60 cases) in normal controls (P = 0.012). FV Leiden, FVCambridge, FVHong Kong, FVAsp79His and FVI359T mutations were not found in two groups. It is concluded that the increased plasma level of FV:C is a risk factor for VTE. There is APCR in both groups, APCR is also a risk factor to VTE. APCR may not be associated with mutations of FV Leiden, FVCambridge, FVHong Kong, FVAsp79His and FV I359T polymorphisms, other factors need to study further in APCR.