title: Comparison of two commercial ELISA systems for evaluating anti-EBNA1 IgG titers.
abstract: High IgG titers against the Epstein-Barr virus nuclear antigen, EBNA-1, have been strongly correlated with the risk of developing multiple sclerosis. ELISAs are used frequently to measure EBNA-1 titers, however concerns remain regarding the accuracy of results. Ordering absolute results into rank quintiles for analysis may be preferable. Using 120 serum samples, two commercially available ELISAs (produced by DiaSorin and VirionSerion) were compared, both in terms of absolute results and rank quintiles. The positive predictive value of the VirionSerion ELISA was 99.1% when compared to the DiaSorin ELISA, however, the negative predictive value was 64.3%. Sensitivity and specificity were acceptable at 95.5% and 90.0%, respectively. There was poor correlation between absolute results, R(2)  = 0.49; and the kappa coefficient for rank quintiles was low at 0.23. Although sensitivity and specificity appear adequate, the poor negative predictive value and kappa coefficient are of major concern. Care must be taken when selecting assays for experimental use.
authors.affiliation: Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University, London, UK. ruth.dobson@qmul.ac.uk
authors.forename: Ruth
authors.initials: R
authors.lastname: Dobson
authors.forename: Joanne
authors.initials: J
authors.lastname: Topping
authors.forename: Gavin
authors.initials: G
authors.lastname: Giovannoni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood*; D019411:Clinical Laboratory Techniques / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D020031:Epstein-Barr Virus Infections / Q000175:diagnosis*; D019309:Epstein-Barr Virus Nuclear Antigens / Q000276:immunology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014773:Virology / Q000379:methods*; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D019309:Epstein-Barr Virus Nuclear Antigens; D007074:Immunoglobulin G; C417029:EBV-encoded nuclear antigen 1