Helicobacter pylori: A Bacterium Influencing and Causing Most of the Diseases in the Upper Gastrointestinal Tract – An Overview with Respect to Pathogenesis and Treatment Based on Basic Physiology

Abstract

The discovery that Helicobacter pylori was the dominating cause of gastritis is among the most important findings in the last century. It gave rise to the understanding and treatment of serious and common diseases, such as peptic ulcer disease and gastric cancer. The gastric hormone gastrin is involved in the pathogenesis of both duodenal ulcer and gastric cancer, whereas reduction in the defense mechanism (mucus and bicarbonate) by the inflammation itself predisposes to gastric ulcer. The search for carcinogenic H. pylori factors has been unsuccessful and based upon the fact that H. pylori predispose to gastric cancer only after having induced oxyntic atrophy is an important argument in favor of a central role of gastrin increase secondary to reduced acidity. The only cell with an undisputed gastrin receptor is the enterochromaffin-like cell where gastrin has a trophic effect leading to hyperplasia, neuroendocrine tumor (NET), and long-term carcinoma of diffuse type. H. pylori may be eradicated by a combination of antibiotics with a potent inhibitor of acid secretion. H. pylori is dependent on acid surrounding to thrive, and therefore anacidity due to complete oxyntic atrophy or profound inhibition of acid secretion by drugs will promote its disappearance.