title: Usefulness of antibody index assessment in cerebrospinal fluid from patients negative for total-IgG oligoclonal bands.
abstract: BACKGROUND
  Testing for cerebrospinal fluid (CSF)-restricted oligoclonal bands (OCB) by isoelectric focusing is used to detect intrathecally produced total IgG. By contrast, antibody indices (AI) are assessed to test for intrathecally produced antigen-specific IgG. A number of previous cases reports have suggested that AI testing might be more sensitive than OCB testing in detecting intrathecal IgG synthesis.
  
  
  RESULTS
  Here we report on 21 patients with positive AI for either herpes simplex virus, varicella zoster virus, cytomegalovirus, measles virus, rubella virus, or Borrelia burgdorferi in the absence of total-IgG OCB and, accordingly, in the presence of a normal total-IgG CSF/serum ratio.
  
  
  CONCLUSIONS
  Our findings indicate that AI testing should not generally be omitted in OCB-negative patients and provide a rationale for systematic and prospective studies on the comparative sensitivity and specificity of AI and total-IgG OCB testing in infectious and other diseases of the CNS.
authors: Division of Molecular Neuroimmunology, Department of Neurology, University of Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany. sven.jarius@med.uni-heidelberg.de.
authors: Sven
authors: S
authors: Jarius
authors: Peter
authors: P
authors: Eichhorn
authors: Brigitte
authors: B
authors: Wildemann
authors: Manfred
authors: M
authors: Wick