title: Evaluation of the effects of strain-specific antigen variation on the accuracy of serologic diagnosis of Helicobacter pylori infection.
abstract: It has been suggested that enzyme immunoassay (EIA) kits validated in one region may yield variable diagnostic performance results in different regions, possibly due to strain-specific differences in antibody responses in different populations. We tested (13)C-urea breath test-characterized serum samples from 109 U.S. patients and 288 Japanese patients using enzyme immunoassay with different preparations of high-molecular-weight cell-associated (HM-CAP) antigens that are conserved across Helicobacter pylori strains. Replicate antigens were prepared from five H. pylori clinical isolates. Eight antigen preparations were evaluated: two of U.S. origin and six of Japanese origin. The accuracies achieved with the eight antigen preparations ranged from 94.4 to 96.3% with the U.S. samples. With the Japanese samples the accuracies achieved ranged from 92.3 to 97.2%. Use of a pool of HM-CAP antigens prepared from isolates from Japan resulted in a higher median enzyme immunoassay value and slightly fewer samples with indeterminate results compared to the results obtained by use of the U.S. standard HM-CAP antigen for H. pylori-positive patients (accuracies, 97.2 and 92.3%, respectively), suggesting that variations in performance between both antigen source and patient population might be reduced by using antigens pooled from several strains.
authors.affiliation: Enteric Products, Inc., Stony Brook, New York, USA. pmarchildon@ezem.com
authors.forename: Patrice A
authors.initials: PA
authors.lastname: Marchildon
authors.forename: Toshiro
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fukuda
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Peacock
authors.forename: Masahiro
authors.initials: M
authors.lastname: Asaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimoyama
authors.forename: David Y
authors.initials: DY
authors.lastname: Graham
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fukada
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D000940:Antigenic Variation; D000942:Antigens, Bacterial / Q000276:immunology; D001944:Breath Tests; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology; D016480:Helicobacter pylori / Q000145:classification* / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D007564:Japan; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014481:United States
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial