title: Evaluation of three fully automated immunoassay systems for detection of IgA anti-beta 2-glycoprotein I antibodies.
abstract: BACKGROUND
  In recent years, we have been witnessing increased clinical interest in the determination of IgA anti-beta 2-glycoprotein I (aB2GPI) antibodies as well as increased demand for this test. Some ELISA-based diagnostic systems for IgA aB2GPI antibodies detection are suboptimal to detect it. The aim of our study was to determine whether the diagnostic yield of modern detection systems based on automatic platforms to measure IgA aB2GPI is equivalent to that of the well-optimized ELISA-based assays.
  
  
  METHODS
  In total, 130 patients were analyzed for IgA aB2GPI by three fully automated immunoassays using an ELISA-based assay as reference. The three systems were also analyzed for IgG aB2GPI with 58 patients.
  
  
  RESULTS
  System 1 was able to detect IgA aB2GPI with good sensitivity and kappa index (99% and 0.72, respectively). The other two systems had also poor sensitivity (20% and 15%) and kappa index (0.10 and 0.07), respectively. On the other hand, kappa index for IgG aB2GPI was >0.89 in the three systems.
  
  
  CONCLUSIONS
  Some analytical methods to detect IgA aB2GPI are suboptimal as well as some ELISA-based diagnostic systems. It is important that the scientific community work to standardize analytical methods to determine IgA aB2GPI antibodies.
authors.affiliation: Department of Immunology, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain. lolaperezmendez@gmail.com.
authors.forename: D
authors.initials: D
authors.lastname: Pérez
authors.affiliation: Department of Immunology, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Martínez-Flores
authors.affiliation: Department of Immunology, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Serrano
authors.affiliation: Epidemiology Section, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Lora
authors.affiliation: Department of Immunology, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain.|Immunology Section, Universidad San Pablo-CEU, Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Paz-Artal
authors.affiliation: Department of Immunology, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Morales
authors.affiliation: Department of Immunology, Instituto de Investigación Hospital Universitario 12 de Octubre, Madrid, Spain.|Immunology Section, Universidad San Pablo-CEU, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Serrano
mesh_terms: D001323:Autoantibodies / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D008297:Male; D053482:beta 2-Glycoprotein I
chemical_list: D001323:Autoantibodies; D007070:Immunoglobulin A; D053482:beta 2-Glycoprotein I
keywords: Antiphospholipid antibodies; IgA; autoantibodies; fully automated immunoassay systems; seronegative antiphospholipid syndrome