Abstract: Objective To evaluate the relationship of clinical symptom to plasmic levels of D-dimer, activated factorⅦ （FⅦa） and tissue factor pathway inhibitor （TFPI）/Ⅹa in patients with urticaria. Methods A total of 27 patients with chronic urticaria （CU）, 27 patients with acute urticaria （AU） and 26 normal human controls were included in this study. Symptom score was determined and disease course was surveyed in these patients. ELISA was used to detect the plasma levels of D-dimer, FⅦa and （TFPI）/Ⅹa in patients and controls. The relation of clinical symptom and disease course to plasma levels of these parameters was assessed. Results In patients with AU and normal controls, the plasma level of D-dimer was 450.57 ± 242.13 ng/mL and 266.81 ± 40.68 ng/mL, respectively, the level of FⅦa, 2.23 ± 0.74 ng/mL and 5.23 ± 1.35 ng/mL, respectively, and the level of TFPI/Ⅹa 0.87 ± 0.13 nmol/L and 0.88 ± 0.12 nmol/L, respectively. There was a significant difference in the level of both D-dimer and FⅦa （both P < 0.01）, whereas no difference was observed in that of TFPI/Ⅹa （P > 0.05） between patients with AU and normal controls. In addition, increased level of D-dimer and decreased level of FⅦa were noticed in patients with CU compared with those in normal controls （593.80 ± 294.04 ng/mL vs 266.81 ± 40.68 ng/mL, 3.98 ± 0.35 ng/mL vs 5.23 ± 1.35 ng/mL, both P < 0.01）, but there was no significant difference in the plasma level of TFPI/Ⅹa（0.87 ± 0.16 nmol/L vs 0.88 ± 0.12 nmol/L, P > 0.05）. Significant difference was observed in the plasma level of D-dimer and FⅦa between patients with AU and CU（450.57 ± 242.13 ng/mL vs 593.80 ± 294.04 ng/mL, P < 0.05; 2.23 ± 0.74 ng/mL vs 3.98 ± 0.35 ng/mL, P < 0.01）. The plasma level of D-dimer positively correlated to the symptom score of patients with CU and those with AU （r = 0.68, P < 0.01; r = 0.82, P < 0.01), but was independent of disease course （P > 0.05）. Neither the level of FⅦa nor that of TFPI/Ⅹa correlated to symptom score or disease course of patients （all P > 0.05）. Conclusions There is an overactivation of coagulation cascade, consumption of blood coagulation factors and secondary fibrinolysis in patients with urticaria, suggesting that plasma D-dimer and FⅦa may be associated with the clinical symptoms of urticaria.

Key words: Urticaria, D-dimer, Activated factor VII, TFPI /Xa