Journal of Research in Medical Sciences1735-19951012005012815ENDepartment of Microbiology, Isfahan University of Medical SciencesDepartment of Microbiology, Isfahan University of Medical SciencesDepartment of Microbiology, Isfahan University of Medical SciencesDepartment of Microbiology, Isfahan University of Medical Sciences2006081520060815Background: This study was conducted to compare the efficacy of enzyme-linked immunosorbent assay (ELISA) for detecting anti-Helicobacter pylori (H. pylori) specific IgG antibodies in specimens of oral fluid and serum with bacteriological tests. Methods: Antral biopsy specimens, as well as serum and oral fluid samples were collected from 97 patients who underwent upper gastrointestinal endoscopy. The presence or absence of current H. pylori infection was determined by culture, histology and urease detection. Anti-H. pylori specific IgG was detected in serum and oral fluid, using an established lab-made, and a commercial ELISA kit. The obtained data were compared with results of bacteriological tests. Results: In all, 62 (64%) of 97 patients were positive for H. pylori by one or more of the gold standard tests (culture, histology and urease detection). Lab-made enzyme-linked immunoassay of oral fluid had a sensitivity and specificity of 92% and 83% respectively. A sensitivity and specificity of 87% and 83%, respectively, was obtained with the commercial kit. Lab-made enzyme-linked immunoassay of serum samples had a sensitivity and specificity of 90% and 88%, respectively. A sensitivity of 86% and specificity of 86% was obtained with the commercial kit. Conclusion: Detection of anti-H. pylori specific IgG in oral fluid by ELISA is comparable in sensitivity and specificity with serum based methods. Oral fluid based ELISA could provide a reliable, non-invasive method for the diagnosis of H. pylori infection. Saliva testing may have a role in epidemiological studies. Keywords: Helicobacter pylori, ELISA, Oral fluidhttp://jrms.mui.ac.ir/index.php/jrms/article/view/342http://jrms.mui.ac.ir/index.php/jrms/article/download/342/128