INTRODUCTION

Helicobacter pylori are gram-negative spiral shaped bacteria that infect more than 50% of humans globally. Helicobacter pylori infection is a serious chronic transmissible infectious disease that causes damage to gastric structure and function and is a major cause of morbidity and mortality worldwide. The prevalence of H. pylori is inversely related to the general health and well-being of a society. However, as with other chronic infectious diseases, the infection remains clinically latent in most with about 20% of infected individuals developing clinically recognizable diseases. The natural niche for the organism is the human stomach, where it causes destructive inflammation (eg, gastritis). Helicobacter pylori is now accepted as the major cause of gastric and duodenal ulcer disease, gastric cancer, and primary B-cell gastric lymphoma. It is also responsible for some cases of nonulcer dyspepsia.

DISCOVERY OF H. PYLORI

In the early 1980s, Robin Warren, a pathologist in Perth, Western Australia, who had observed small curved bacteria in gastric biopsy specimens, teamed up with a young trainee in internal medicine, Barry Marshall, to further investigate the role of these bacteria in human disease. By 1982, with a bit of luck, Marshall successfully isolated the organism from biopsy specimens. The organism was initially named Campylobacter pyloridis based on the insight from Warren that the organism looked like a Campylobacter. That organism is now known as H. pylori and is a microaerophilic, gram-negative, spiral rod approximately 0.6 × 3.5 μ with approximately 7 unipolar flagellae.