Campylobacter pylori in health and disease: An ecological perspective

Abstract

The successful isolation by Marshall in 1984 of a spiral-shaped bacterium, at present called Campylobacter pylori, has sparked a resurgence of interest in the role of bacteria in stomach disease. C. pylori has been shown to be the causative agent of active chronic gastritis in humans. There is also accumulating evidence that this organism plays a significant role in the initiation of duodenal ulcers. The association of this organism with the human stomach is reviewed with an ecological bias. It is suggested that C. pylori is a member of a group of highly adapted mucus colonising bacteria that inhabit the gastrointestinal surfaces of all animals studied. The natural niche of C. pylori is the human stomach; over the period of evolution the organism has become well suited to the environment of gastric mucus and gastric epithelium. However C. pylori is only ‘almost’ normal flora as is always associated with a pathology albeit mild and most often asymptomatic. Understanding the factors that allow colonisation of the gastric mucosa, e.g. possibly morphology, special motility, microaerophilism, urease activity etc., provides a rational basis for the selection of appropriate methods of treatment and prophylaxis. There is a need to identify the ‘triggers’ to C. pylori associated symptomatology. An ecological approach to the microbiology, histopathology, symptomatology, and epidemiology of C. pylori infection in humans could resolve some of the controversy over the role of this organism in peptic and duodenal disease.