Alimentary TractGeographic distribution of vacA allelic types of Helicobacter pylori☆,☆☆
Section snippets
H. pylori cultures
A total of 735 H. pylori cultures were obtained from the following countries: Australia (n = 28), Brazil (n = 57), Canada (n = 13), Czech Republic (n = 13), China (n = 6), Colombia (n = 6), Costa Rica (n = 36), Egypt (n = 33), France (n = 58), Germany (n = 22), Hong Kong (n = 52), Hungary (n = 14), Italy (n = 32), Japan (n = 12), The Netherlands (n = 96), Peru (n = 6), Poland (n = 23), Portugal (n = 92), Romania (n = 23), Spain (n = 9), Sweden (n = 18), Thailand (n = 4), the United Kingdom (n =
Results
The geographic distribution of the vacA allelic types was investigated by analysis of 735 H. pylori cultures obtained from patients in 24 countries. In 124 (16.9%) of the 735 cultures, multiple vacA genotypes were detected in either the s-region (29.8%), the m-region (37.9%), or both (32.3%). The prevalence of cultures containing multiple strains varied between countries. In northern Europe, France, and Italy, only 34 (10.6%) of the 321 cultures contained multiple vacA types, whereas in
Discussion
H. pylori has a worldwide distribution, and the prevalence ranges from approximately 25% in developed countries to more than 80% in the developing world.38, 39 However, the incidence of H. pylori–associated diseases is not evenly distributed around the globe, even when correcting for H. pylori prevalence. This phenomenon may be due to heterogeneous host genetic factors, socioeconomic status, and environmental differences36, 40, 41, 42 or to the existence of distinct H. pylori genotypes.8, 9
Acknowledgements
The authors thank Drs. C. Pinho and J.M. Soares (Department of Gastroenterology, Hospital S. António, Porto, Portugal) and C.L.A.M. van Hoek (Delft Diagnostic Laboratory, Delft, the Netherlands).
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Address requests for reprints to: Leen-Jan van Doorn, Ph.D., Delft Diagnostic Laboratory, R. de Graafweg 7, 2625 AD, Delft, The Netherlands. e-mail: [email protected]; fax: (31) 15-2604550.
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Supported by Project 1/2.1/SAU/1356/95 from Portuguese Foundation for Science and Technology (PRAXIS XXI) (to C.F.); in part by R01 DK 53707 from the National Institutes of Health and the Medical Research Service of the Department of Veterans Affairs; and by Financiadora de Projectos and Consellio Nacional de Desenvolvimento Cientifico e Tecnologico-Brazil (to D.M.M.Q.).