RESUMEN
Omeprazole may not eradicate helicobacter pylori from the stomach but rather displace it from the antrum to the stomach body. This fact could interfere with colonization studies in patients receiving the drug. The aim of this study was to assess the presence of helicobacter pylori, defined as a positive wrease test, culture or microscopical examination, in antral and gastric body biopsies in patients receiving treatment with omeprazole. Sixty four paired antral and gastric body biopsies obtained at the end of a 28 day course of omeprazole, 62 obtained 4 months later, 40 obtained 8 months later and 23 obtained 12 months later were analized. there was a 92 percent concordance between antral and gastric body biopsies for the presence of helicobacter pylori. However, 9 of the samples obtained at 28 days (14 percent) were negative for H. pylori in the antrum but positive in the gastric body. It is concluded that for early assessment of helicobacter pylori eradication after omeprazole treatment, paired biopsies of antral and gastric body are needed