ABSTRACT
A. Helicobacter pylori Spiral organisms were demonstrated in animal stomach by Rappin as long ago as 1881. In 1938, spiral organisms were also identified in human gastric tissue by Doenges but were considered to be commensal organisms, and therefore interest in them waned. Further confmnation that the human stomach was colonized by spiral-shaped organisms was made in 1975 by Steer who noted for the first time that there was an association with inflammation; a possible link with duodenal ulceration was suggested. It was not until the appropriate culture techniques were available, however, that these organisms were isolated from the human stomach in 1983 by Warren and Marshall (1). Warren again noted that the organisms were associated with gastritis and made the suggestion that they may be related to ulceration. This was met with some widespread skepticism because duodenal ulceration was believed to be caused by excess stomach acid: the "no acid-no ulcer" hypothesis. Gradually, however, with accumulating clinical and scientific evidence, a paradigm shift in medical opinion has occurred, and an increasing number of physicians (although some non-believers still remain) have become convinced that H. pylori is causally related to gastro-duodenal disease: the "no H. pylori-no ulcer" hypothesis. This paradigm shift has had enormous implications for treatment because ulcers can now be cured by a short eradicative course of antibiotics (instead of continuous acid-suppressive medication only). The 'campylobacter-like organism' (CLO) isolated by Warren has been called at various times, Campylobacter pylori or Campylobacter pyloridis; only receiving its current name of H. pylori in 1989 (2) when it was convincingly demonstrated that it was a novel genus and that it did not belong to the genus Campylobacter. The or-
ganism's complete genome sequence was fIrst published in the August issue of Nature (3) in 1997 thus testifying to its current perceived importance as a human pathogen.
