TY - JOUR T1 - Helicobacter pylori infection as a cause of gastritis, duodenal ulcer, gastric cancer and nonulcer dyspepsia: a systematic overview JF - Canadian Medical Association Journal JO - CMAJ SP - 177 LP - 185 VL - 150 IS - 2 AU - S. J. Veldhuyzen van Zanten AU - P. M. Sherman Y1 - 1994/01/15 UR - http://www.cmaj.ca/content/150/2/177.abstract N2 - OBJECTIVE: To evaluate current evidence for a causal relation between Helicobacter pylori infection and gastritis, duodenal ulcer, gastric cancer and nonulcer dyspepsia. DATA SOURCES: A MEDLINE search for articles published in English between January 1983 and December 1992 with the use of MeSH terms Helicobacter pylori, gastritis, duodenal ulcer, gastric cancer, dyspepsia and clinical trial; abstracts were excluded. Six journals and Current Contents were searched manually for pertinent articles published in that time frame. STUDY SELECTION: Original studies with at least 25 patients, case reports and reviews that examined the relation between H. pylori and the four gastrointestinal disorders; 350 articles were on gastritis, 122 on duodenal ulcer, 44 on gastric cancer and 96 on nonulcer dyspepsia. DATA EXTRACTION: The quality of the studies was rated independently on a four-point scale. The strength of the evidence was assessed using a six-point scale for each of the eight established guidelines for determining a causal relation. DATA SYNTHESIS: There was conclusive evidence of a causal relation between H. pylori infection and histologic gastritis. Koch's postulates for the identification of a microorganism as the causative agent of a disease were fulfilled for H. pylori as a causative agent of gastritis. There was strong evidence that H. pylori is the main cause of duodenal ulcers not induced by nonsteroidal anti-inflammatory drugs, but all of Koch's postulates were not fulfilled. There was moderate epidemiologic evidence of an association between chronic H. pylori infection and gastric cancer. There was a lack of convincing evidence of a causal association between H. pylori and nonulcer dyspepsia. CONCLUSIONS: The evidence supports a strong causal relation between H. pylori infection and gastritis and duodenal ulcer and a moderate relation between such infection and gastric cancer. Further studies are needed to clarify the role of H. pylori in these disorders. Thus far, there is no evidence of a causal relation between H. pylori and nonulcer dyspepsia. ER -