title: The clinical significance of anti-prothrombin antibodies for risk assessment of thromboembolism in patients with lupus anticoagulant.
abstract: BACKGROUND
  Thromboembolism is a common manifestation of lupus anticoagulant (LA), however only a subgroup of LA-patients is affected by thrombosis. Study objective was to investigate whether anti-prothrombin antibodies can identify LA-patients at increased risk for thrombosis.
  
  
  METHODS
  In total 79 patients, 50 with (42 men/8 women) and 29 without thrombosis (21 men/8 women), were investigated for their presence of anti-prothrombin IgG and IgM antibodies using assays from two different manufacturers (Aeskulisa=assay I, CoaChrom=assay II).
  
  
  RESULTS
  The prevalence of elevated levels of anti-prothrombin IgG, IgM as well as IgG and/or IgM antibodies was 66% [assayI] (36% [assayII]), 38% (24%) and 72% (50%) in patients with thrombosis and 55% (24%), 28% (28%) and 66% (41%) in patients without thrombosis, respectively. Neither anti-prothrombin IgG or IgM nor IgG and/or IgM antibodies were found to indicate an increased risk for thrombosis. In the subgroup of patients with arterial or venous thrombosis there was also no association between anti-prothrombin antibodies and thrombosis. The comparison of median levels of IgG and IgM anti-prothrombin antibodies between patients with and without thrombosis yielded a borderline statistically significant difference only for anti-prothrombin IgG antibodies by using assay II (p=0.033), all other comparisons were not statistically significant.
  
  
  CONCLUSIONS
  In conclusion, presence of anti-prothrombin antibodies was not associated with thromboembolism in LA-patients.
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Sailer
authors.forename: Rainer
authors.initials: R
authors.lastname: Vormittag
authors.forename: Claudia
authors.initials: C
authors.lastname: Zoghlami
authors.forename: Silvia
authors.initials: S
authors.lastname: Koder
authors.forename: Peter
authors.initials: P
authors.lastname: Quehenberger
authors.forename: Christoph
authors.initials: C
authors.lastname: Male
authors.forename: Ingrid
authors.initials: I
authors.lastname: Pabinger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016682:Lupus Coagulation Inhibitor / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011516:Prothrombin / Q000276:immunology*; D012189:Retrospective Studies; D012307:Risk Factors; D013923:Thromboembolism / Q000097:blood / Q000209:etiology* / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D016682:Lupus Coagulation Inhibitor; D011516:Prothrombin