Helicobacter Pylori: The Organism, the Disease, the Clinical Picture, the Current Research
In infected patients, 30%-35% have no symptoms.
One theory proposes the role of H. pylori as the etiological agent of a modern disease: peptic ulcer disease and as a major risk factor for the development of distal gastric cancer. A series of studies suggested that peptic ulcer disease and gastric cancer are diseases related to modern times. The prevalence and incidence of these diseases rose at the end of the 18th century and peaked by the 19th century. There is a potential explanation that may account for both conflicting points of view of H. pylori’s etiological role in peptic ulcer disease and as the major risk factor for the development of gastric cancer. Peptic ulcer disease and gastric cancer are indeed very ancient diseases, but because the number of cases related to these diseases was insignificant until the second half of the 18th century they have been suggested to be modern diseases. However, increased life expectancy in new industrialized countries, specifically the UK and US, may explain the escalation of peptic ulcer disease and gastric cancer cases. Several studies indicated major changes in life expectancy, from less than 45 years in the 18th century to more than 60 years by the 19th century in the same countries.
How long humans carried H. pylori is still a debatable issue. However, it is accepted that this organism has colonized humans possibly for many thousands of years, and the successful persistence of H. pylori in human stomach for such a long period may be a case to conceive that this organism is advantageous to its host (Chow WH, Blaser MJ, 1998).
de Martel C, Llosa AE, Farr SM, Friedman GD, Vogelman JH, Orentreich N, Corley DA, Parsonnet J. Helicobacter pylori infection and the risk of development of esophageal adenocarcinoma. J Infect Dis. 2005
Chow WH, Blaser MJ, Blot WJ, Gammon MD, Vaughan TL, Risch HA, Perez-Perez GI, Schoenberg JB, Stanford JL, Rotterdam H, West AB, Fraumeni JF., Jr An Inverse relation between cagA+ strains of Helicobacter pylori infection and risk of esophageal and gastric cardia adenocarcinoma. Cancer Res. 1998
Graham DY. Helicobacter pylori, GERD, NSAIDs, and cancer: where we really stand. Am J Gastroenterol. 1999
Warburton-Timms VJ, Charlett A, Valori RM, Uff JS, Shepherd NA, Barr H, McNulty CA. The significance of cagA (+) Helicobacter pylori in reflux oesophagitis. Gut. 2001