title: ["Idiopathic" white atrophy].
abstract: BACKGROUND
  Livedoid vasculitis is a clinico-pathological entity which may be idiopathic or secondary to various disorders. The aim of this study was to search for a thrombogenic biological abnormality in patients with apparently idiopathic livedoid vasculitis.
  
  
  METHODS
  All the patients with histologically confirmed and apparently idiopathic livedoid vasculitis were evaluated. Blood study included search for anticardiolipin, anti-anionic phospholipids and anti-beta 2 glycoprotein 1 antibodies, platelet aggregation and fibrinolytic system tests, cryofibrinogen and homocysteine serum level and factor V Q506 mutation and prothrombin 20210 G/A variant investigation. Clinical data and effects of treatments were reviewed retrospectively.
  
  
  RESULTS
  Eleven of the 21 patients with livedoid vasculitis had an apparently idiopathic form. Seven of them (64 p. 100) had a thrombophilic state: antiphospholipid antibodies (n = 3), increased platelet aggregation (n = 1), cryofibrinogen (n = 1), decreased antithrombin III activity (n = 1) and factor V mutation (n = 1). The necrotic lesions were always localized on the lower limbs with a sensitive neuropathy in 2 cases. Complete remission was sometimes obtained with antiaggregant or anticoagulant therapy, but was unrelated to the thrombophilic abnormalities.
  
  
  CONCLUSIONS
  Various thrombophilic abnormalities are frequently observed in livedoid vasculitis which seems to be the clinical expression of a thrombotic process of the microcirculation of the skin and sometimes of the peripheral nerves. The idiopathic feature of numerous cases gives evidence for the lack of our knowledge on thrombosis of the microcirculation.
authors.affiliation: Service de Médecine Interne, Groupe Hospitalier Pitié-Salpêtrière, Paris.
authors.forename: M D
authors.initials: MD
authors.lastname: Tran
authors.forename: P A
authors.initials: PA
authors.lastname: Bécherel
authors.forename: N
authors.initials: N
authors.lastname: Cordel
authors.forename: J C
authors.initials: JC
authors.lastname: Piette
authors.forename: C
authors.initials: C
authors.lastname: Francès
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017445:Skin Diseases, Vascular / Q000473:pathology*