title: Autoantibodies to human prothrombin and clinical manifestations in 207 patients with systemic lupus erythematosus.
abstract: OBJECTIVE
  Prothrombin (factor II) is one of the phospholipid binding proteins with a procoagulant property. Some publications have shown the presence of autoantibodies against prothrombin (aPT) in patients with antiphospholipid antibodies (aPL). We assessed the clinical significance of aPT in thrombotic events in patients with systemic lupus erythematosus (SLE).
  
  
  METHODS
  IgG and IgM aPT were tested by ELISA in 207 patients with SLE.
  
  
  RESULTS
  Fifty-eight patients (28%) had positive aPT (> mean + 3 SD of 100 controls). Twenty-eight (14%) had IgG alone, 21 (10%) IgM alone, and 9 (4%) had both IgG and IgM. Patients with aPT had a history of thrombosis more frequently than those without aPT [31/58 (53%) vs 47/149 (32%), chi-squared=7.6, p=0.006]. No correlation was found between the presence of aPT and clinical features of SLE.
  
  
  CONCLUSIONS
  aPT are frequently found in patients with SLE, and are a potential marker for thrombosis.
authors.affiliation: Lupus Research Unit, The Rayne Institute, St. Thomas' Hospital, London, UK.
authors.forename: M L
authors.initials: ML
authors.lastname: Bertolaccini
authors.forename: T
authors.initials: T
authors.lastname: Atsumi
authors.forename: M A
authors.initials: MA
authors.lastname: Khamashta
authors.forename: O
authors.initials: O
authors.lastname: Amengual
authors.forename: G R
authors.initials: GR
authors.lastname: Hughes
mesh_terms: D000022:Abortion, Spontaneous / Q000276:immunology; D000293:Adolescent; D000328:Adult; D000368:Aged; D017153:Antibodies, Anticardiolipin / Q000097:blood; D017152:Antibodies, Antiphospholipid / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis*; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D016682:Lupus Coagulation Inhibitor / Q000097:blood; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology* / Q000473:pathology; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D008875:Middle Aged; D011247:Pregnancy; D011516:Prothrombin / Q000276:immunology*; D012680:Sensitivity and Specificity; D013927:Thrombosis / Q000150:complications / Q000276:immunology*; D053482:beta 2-Glycoprotein I
chemical_list: D017153:Antibodies, Anticardiolipin; D017152:Antibodies, Antiphospholipid; D001323:Autoantibodies; D006023:Glycoproteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D016682:Lupus Coagulation Inhibitor; D008562:Membrane Glycoproteins; D053482:beta 2-Glycoprotein I; D011516:Prothrombin