title: Role of antiphospholipid score and anti-β2-glycoprotein I Domain I autoantibodies in the diagnosis of antiphospholipid syndrome.
abstract: BACKGROUND
  Antiphospholipid syndrome (APS) is characterized by the presence circulating antiphospholipid (aPL) antibodies in patients with thrombosis or pregnancy morbidity. Recently it has been shown that multiple positive results define a higher risk of clinical manifestation in APS patients. However, utilizing combined results generates challenges for a physician. Therefore, the antiphospholipid score. (aPL-S), a new variable that encompasses all aPL assays, has been described. We analyze clinical performance of different aPL-Ss based on ELISA or chemiluminescent immunoassays (CIAs).
  
  
  METHODS
  A total of 39 patients and 77 controls were included in this study. All patients were tested for lupus anticoagulant (LAC). In addition, IgM/IgG anticardiolipin (aCL) and anti-β2 glycoprotein 1 (aβ2GP1) autoantibodies were tested by ELISA and CIA. Anti-β2GP1 Domain 1 IgG (D1) autoantibodies were tested by CIA. Three aPL-Ss were calculated (ELISA, CIA and CIA with D1 instead of β2GP1 IgG) using the Otomo equation: aPL-S=5×exp([OR]-5)/4.
  
  
  RESULTS
  IgG assays showed a good correlation while IgM assays showed moderate correlation. The relative risk of having clinical manifestation of APS was calculated for each aPL test. All three aPL-Ss were higher in individuals with thrombosis or pregnancy morbidity than in those without APS manifestations (p<0.001) and the prevalence of APS manifestations increased with increasing aPL-Ss.
  
  
  CONCLUSIONS
  The CIAs are comparable with the ELISAs for the detection of aPL antibodies. aβ2GPI-D1 antibodies seem to represent a strong indicator for clinical manifestations of APS. Any of the aPL-Ss studied represents a useful quantitative index for APS diagnosis and could be helpful to physicians in managing APS.
authors: Virgen Macarena University Hospital, Seville, Spain.
authors: R
authors: R
authors: Mondejar
authors: Virgen Macarena University Hospital, Seville, Spain. Electronic address: concepcion.gonzalez.r.sspa@juntadeandalucia.es.
authors: C
authors: C
authors: González-Rodríguez
authors: Virgen Macarena University Hospital, Seville, Spain.
authors: F J
authors: FJ
authors: Toyos-Sáenz de Miera
authors: Virgen Macarena University Hospital, Seville, Spain.
authors: E
authors: E
authors: Melguizo-Madrid
authors: INOVA Diagnostics, Inc., San Diego, CA, USA.
authors: N
authors: N
authors: Zohoury
authors: INOVA Diagnostics, Inc., San Diego, CA, USA.
authors: M
authors: M
authors: Mahler
authors: Virgen Macarena University Hospital, Seville, Spain.
authors: I
authors: I
authors: Romero Losquiño
authors: Virgen Macarena University Hospital, Seville, Spain.
authors: F
authors: F
authors: Fabiani
mesh_terms: D000328:Adult; D017152:Antibodies, Antiphospholipid / Q000097:blood*; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D002308:Cardiolipins / Q000276:immunology; D005260:Female; D006801:Humans; D049449:Luminescence; D016682:Lupus Coagulation Inhibitor / Q000032:analysis; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D053482:beta 2-Glycoprotein I / Q000276:immunology*
chemical_list: D017152:Antibodies, Antiphospholipid; D002308:Cardiolipins; D016682:Lupus Coagulation Inhibitor; D053482:beta 2-Glycoprotein I
keywords: Antiphospholipid syndrome; Autoantibodies; Beta 2 glycoprotein I Domain 1; Thrombosis