title: Activation of the Intrinsic Coagulation Pathway in Patients With Chronic Urticaria.
abstract: OBJECTIVE
  Although coagulation activation has been reported in chronic urticaria, data pertaining to detailed changes in coagulation factors and global coagulation status are lacking. The current study evaluated global coagulation status in patients with chronic urticaria using thrombin generation assay (TGA) and the levels of individual coagulation factors.
  
  
  METHODS
  Patients with chronic urticaria (n=57) and 20 healthy controls were enrolled. TGA was performed under stimulation with 2 concentrations of tissue factor (TF). Coagulation factors and conventional coagulation assays were also analyzed.
  
  
  RESULTS
  Although patients with chronic urticaria showed prolonged activated partial thromboplastin time, prothrombin time did not differ significantly between patients and controls. In both 1 pM and 5 pM TF-stimulated TGA, peak thrombin and endogenous thrombin potential (ETP) levels were markedly decreased in patients with chronic urticaria. As expected, intrinsic coagulation factors (VIII, IX, and XII), as well as coagulation factors of the common pathway (II, V, and X), were consistently decreased. Additionally, D-dimer was significantly increased in patients as compared to controls. In multivariate regression analysis, the presence of chronic urticaria was the only significant independent contributor to the low ETP value.
  
  
  CONCLUSIONS
  Chronic urticaria is characterized by in vivo coagulation activation through the intrinsic coagulation pathway, which can be measured with sensitivity using TGA.
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jung Ah
authors.identifier: http://orcid.org/0000-0001-6934-1987
authors.initials: JA
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.; Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Sujeoung
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea.; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea.; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Ja Yoon
authors.initials: JY
authors.lastname: Gu
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea.; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Yoo
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. helenmed@snu.ac.kr.
authors.forename: Hye Ryun
authors.initials: HR
authors.lastname: Kang
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea.; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea. lukekhk@snu.ac.kr.
authors.forename: Hyun Kyung
authors.initials: HK
authors.lastname: Kim
keywords: Chronic urticaria; coagulation factors; contact pathway; intrinsic coagulation pathway; thrombin generation assay