A century ago the Italian pathologist Bizzozero described the relationships between spiral bacteria and the mammalian gastro intestinal tract. Since 1982, when Helicobacter pylori was discovered, gastroduodenal disease have been completely revised as a con sequence of the results of basic and clinical research in this field. Progress in understanding the pathogenesis of this bacterium has been made by studying H. pylori infection in animal models. More specific diagnostic tools have been developed using new molecular biology techniques. Future trends are directed towards preparing a specific H. pylori vaccine. A new classification for gastritis, the Sydney System, including H. pylori gastritis, was proposed in 1990. As concerns the clinical approach to peptic ulcer disease in the 1990's, the majority of authors agree on the importance of H. pylori eradication. Moreover, recent clinical studies suggest that H. pylori infection can be associated with other gastroduodenal diseases, such as non ulcer dyspepsia and gastric cancer. Multicenter trials to standardize serological methods and evaluate the efficacy of new antimicrobial therapy schedules are planned throughout different European countries. The fourth Workshop of the European Helicobacter Pylori Study Group was held in Bologna, Italy, in November 1991. Two years before Bologna University celebrated its ninth centennial, giving evidence of being the oldest University in the modern world. Thus the H. pylori story that has continued for more than a century has been discussed once again at the University with the oldest tradition in the world.

Helieobaeter pylori has recently been recognized as a new genus according to specific taxonomic criteria; the "popular" name Campylobaeter pylori has been corrected by scientific progress. Following the discovery of the spiral microorgan ism in gastric mucosa by Marshall and Warren in 1982, it took only a few years for H. pylori to become established as a factor in the pathogenesis of gastritis and peptic ulcer disease. Interest in different aspects of H. pylori has grown continuously and has attracted scientists from various medical and biological disciplines such as gastroenterology, microbiology, pathology, immunology, and pharmacology. Indeed H. pylori provides an excellent model for interdisciplinary interaction and cooperation. To promote this concept of interdisciplinary research and exchange of knowledge, a European Campylobacter (Helicobacter) Pylori Study Group was founded in 1987 in Copenhagen. The second meeting of this expanding group was held from October 12-14,1989 in Ulm, FRG. The fact that more than 500 participants attended the conference and that 187 original contributions from all five continents were presented clearly confirmed that H. pylori has "scientifically infected" the whole world. Our understanding of the microbiological and pathogenetic aspects of H. pylori is continuously being challenged as new results follow swifthy from different research areas. This book includes an update and progress report on the various aspects of H. pylori presented and discussed in special workshops held during the meeting in Ulm.

Helieobaeter pylori has recently been recognized as a new genus according to specific taxonomic criteria; the "popular" name Campylobaeter pylori has been corrected by scientific progress. Following the discovery of the spiral microorgan ism in gastric mucosa by Marshall and Warren in 1982, it took only a few years for H. pylori to become established as a factor in the pathogenesis of gastritis and peptic ulcer disease. Interest in different aspects of H. pylori has grown continuously and has attracted scientists from various medical and biological disciplines such as gastroenterology, microbiology, pathology, immunology, and pharmacology. Indeed H. pylori provides an excellent model for interdisciplinary interaction and cooperation. To promote this concept of interdisciplinary research and exchange of knowledge, a European Campylobacter (Helicobacter) Pylori Study Group was founded in 1987 in Copenhagen. The second meeting of this expanding group was held from October 12-14,1989 in Ulm, FRG. The fact that more than 500 participants attended the conference and that 187 original contributions from all five continents were presented clearly confirmed that H. pylori has "scientifically infected" the whole world. Our understanding of the microbiological and pathogenetic aspects of H. pylori is continuously being challenged as new results follow swifthy from different research areas. This book includes an update and progress report on the various aspects of H. pylori presented and discussed in special workshops held during the meeting in Ulm.