Activation of coagulation, anti-coagulation, fibrinolysis and the complement system in patients with urticaria.

BACKGROUND Recently released studies indicate that activation of blood coagulation may be involved in causing urticaria. OBJECTIVE To evaluate whether or not anticoagulation, fibrinolysis and the complement system are also involved in the pathogenesis of urticaria. METHODS Coagulant factors, anticoagulant factors, fibrinolytic markers and complement components were analysed in patients with acute urticaria (AU) and chronic urticaria (CU). Conclusion: The activation of coagulation, anti-coagulation, fibrinolysis and the complement system may be involved in the pathogenesis of urticaria. It also indicates that coagulation conditions in CU patients can recover after antihistamine treatment, but do not immediately return to normal levels directly after administration. RESULTS Plasma levels of activated factor VII (FVIIa) were higher in AU patients (P <0.01) but not significantly different in CU patients (P >0.05), while levels of the thrombin-antithrombin complex (TAT) and prothrombin fragment 1+2 (F1+2) were significantly higher in CU patients (P <0.01). Levels of factor IX (FIX) and tissue factor (TF) were lower in CU patients (P <0.01). Plasma levels of tissue factor pathway inhibitor/activated factor X (TFPI/Xa) were higher in CU patients (P <0.01) but not significantly different in AU patients (P >0.05), whereas levels of thrombomodulin (TM) were lower in CU patients (P <0.01). Plasma levels of D-dimer in AU and CU patients and levels of high molecular weight kininogen (HMWK) in CU patients were increased significantly (P <0.01), while levels of tissue-type plasminogen activator (t-PA) were decreased (P <0.01). Plasma concentrations of C5a in CU patients were superior to those in healthy controls (P <0.01). Serum levels of C4 also increased (P <0.01). CONCLUSION The activation of coagulation, anti-coagulation, fibrinolysis and the complement urticaria. It also indicates that coagulation conditions in CU patients can recover after antihistamine treatment, but do not immediately return to normal levels directly after administration.