title: [Antiphospholipid antibodies and the risk of thrombosis: a comparative survey between chronic immune thrombocytopenia and primary antiphospholipid syndrome].
abstract: OBJECTIVE
  The prevalence of antiphospholipid antibodies (APA) in patients with immune thrombocytopenic purpura (ITP) varies from 25 to 75% in the literature. The risk of thrombosis in this subgroup of patients is debated. In parallel, thrombocytopenia is present in 22 to 42% of patients with antiphospholipid syndrome (APS).
  
  
  METHODS
  The main study objective was to compare the profile at diagnosis of lupus anticoagulant (LA), anticardiolipin antibody (ACL) and anti-β(2)GP-I antibody between a cohort of 93 chronic ITP patients and a cohort of 27 primary APS patients. The secondary objectives were: to evaluate the risk of thrombosis in ITP patients depending on the presence of APA; to compare the profile of APA and to assess the occurrence of lupus in APS patients depending on the presence of thrombocytopenia.
  
  
  RESULTS
  In ITP patients, the prevalence of APA was 25%; association of several different APA was less frequent than in APS patients; mean titles of ACL and anti-β(2)GP-I antibodies were comparable between the two cohorts; two spontaneous venous thromboses occurred in ITP patients, with no particular profile of APA (median follow-up: 36 months). Thrombocytopenia was present in 26% of APS patients; it was always moderate and asymptomatic, and sometimes intermittent; no particular profile of APA was associated to thrombocytopenia; only one thrombocytopenic patient developed a systemic lupus and no particular profile of APA could be found associated (median follow-up: 48 months).
  
  
  CONCLUSIONS
  ITP patients with APA have less frequently an association of different APA than APS patients do; their risk of thrombosis appears low.
authors.affiliation: Service de médecine interne, Université de Toulouse, Toulouse cedex, France. gmoulis@hotmail.com
authors.forename: G
authors.initials: G
authors.lastname: Moulis
authors.forename: K
authors.initials: K
authors.lastname: Delavigne
authors.forename: F
authors.initials: F
authors.lastname: Huguet
authors.forename: F
authors.initials: F
authors.lastname: Fortenfant
authors.forename: O
authors.initials: O
authors.lastname: Beyne-Rauzy
authors.forename: D
authors.initials: D
authors.lastname: Adoue
mesh_terms: D000328:Adult; D017152:Antibodies, Antiphospholipid / Q000032:analysis / Q000097:blood*; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000150:complications* / Q000453:epidemiology / Q000276:immunology; D002908:Chronic Disease; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000150:complications* / Q000453:epidemiology / Q000276:immunology; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013927:Thrombosis / Q000097:blood / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology
chemical_list: D017152:Antibodies, Antiphospholipid