Hyperhomocysteinemia and hypercoagulability in primary biliary cirrhosis.

To assess the hypercoagulability in PBC and its relationship with homocysteine (HCY) and various components of the haemostatic system.We investigated 51 PBC patients (43F/8M; mean age: 63+/-13.9 yr) and 102 healthy subjects (86 women/16 men; 63+/-13 yr), and evaluated the haemostatic process in whole blood by the Sonoclot analysis and the platelet function by PFA-100 device. We then measured HCY (fasting and after methionine loading), tissue factor (TF), thrombin-antithrombin complexes (TAT), D-dimer (D-D), thrombomodulin (TM), folic acid, vitamin B6 and B12 plasma levels. C677T 5,10-methylenetetrahydrofolate reductase (MTHFR) polymorphism was analyzed.Sonoclot RATE values of patients were significantly (P<0.001) higher than those of controls. Sonoclot time to peak values and PFA-100 closure times were comparable in patients and controls. TAT, TF and HCY levels, both in the fasting and post-methionine loading, were significantly (P<0.001) higher in patients than in controls. Vitamin deficiencies were detected in 45/51 patients (88.2\%). The prevalence of the homozygous TT677 MTHFR genotype was significantly higher in patients (31.4\%) than in controls (17.5\%) (P<0.05). Sonoclot RATE values correlated significantly with HCY levels and TF.In PBC, hyper-HCY is related to hypovitaminosis and genetic predisposing factors. Increased TF and HCY levels and signs of endothelial activation are associated with hypercoagulability and may have an important role in blood clotting activation.