title: Activation of coagulation in chronic urticaria in relation to disease severity and activity.
abstract: BACKGROUND
  The pathogenesis of chronic urticaria is incompletely understood. There is growing interest in the role of the coagulation cascade in chronic urticaria. We aimed to assess the possible activation of the coagulation cascade in chronic spontaneous urticaria (CSU) in relation to disease severity and activity.
  
  
  METHODS
  This study was conducted on 30 patients with active CSU and 30 apparently healthy individuals as controls. Patients with acute urticaria, physical urticaria, or any form of urticaria other than spontaneous urticaria were excluded. Plasma levels of D-dimer and activated factor VII (FVIIa) were measured by ELISA at baseline for all recruited patients and controls. In addition, they were measured for CSU patients after complete disease remission.
  
  
  RESULTS
  Plasma levels of D-dimer and FVIIa were significantly higher among patients with active CSU than among healthy controls. D-dimer levels were lowest among patients with grade 1 severity and highest among those with grade 4 severity. Factor VIIa levels did not differ significantly according to disease severity grades. After complete disease remission, there was a significant dramatic drop in levels of D-dimer and FVIIa among patients.
  
  
  CONCLUSIONS
  We conclude that activation of the coagulation cascade occurs in CSU, and we demonstrate the novel finding that activated factor VII levels are significantly reduced after medical therapy, confirming the implication of the extrinsic pathway activation in CSU. Future controlled studies may investigate the role of anticoagulant therapy in refractory chronic urticaria.
authors.affiliation: Department of Allergy and Clinical Immunology, Faculty of Medicine, Ain Shams University, Cairo, Egypt. Electronic address: mnfarris@yahoo.co.uk.
authors.forename: M N
authors.initials: MN
authors.lastname: Farres
authors.affiliation: Department of Allergy and Clinical Immunology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: M
authors.initials: M
authors.lastname: Refaat
authors.affiliation: Department of Allergy and Clinical Immunology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: N A
authors.initials: NA
authors.lastname: Melek
authors.affiliation: Department of Allergy and Clinical Immunology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: E E
authors.initials: EE
authors.lastname: Ahmed
authors.affiliation: Egyptian Ministry of Health and Population, Cairo, Egypt.
authors.forename: M G
authors.initials: MG
authors.lastname: Shamseldine
authors.affiliation: Department of Community, Environmental and Occupational Medicine, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
authors.forename: N A
authors.initials: NA
authors.lastname: Arafa
mesh_terms: D000328:Adult; D001777:Blood Coagulation; D016022:Case-Control Studies; D002908:Chronic Disease; D018450:Disease Progression; D015942:Factor VIIa / Q000378:metabolism*; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism*; D005500:Follow-Up Studies; D006634:Histamine H1 Antagonists / Q000627:therapeutic use; D006801:Humans; D008297:Male; D012720:Severity of Illness Index; D014581:Urticaria / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy; D055815:Young Adult
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; D006634:Histamine H1 Antagonists; C036309:fibrin fragment D; D015942:Factor VIIa
keywords: Chronic urticaria; Coagulation; D-dimer; Extrinsic pathway; Factor VII; Fibrinolysis