Does Helicobacter pylori really cause duodenal ulcers? NoBMJ 2009; 339 doi: https://doi.org/10.1136/bmj.b2788 (Published 14 August 2009) Cite this as: BMJ 2009;339:b2788
- Michael Hobsley, emeritus professor of surgery1,
- Frank I Tovey, honorary senior research associate1,
- Karna Dev Bardhan, consultant physician and gastroenterologist 2,
- John Holton, reader in clinical microbiology3
- 1University College London Medical School, London N20 8AS
- 2Rotherham General Hospital, Rotherham
- 3Windeyer Institute for Medical Sciences, University College London
- Correspondence to: M Hobsley
Helicobacter pylori and duodenal ulcer are linked. However, association does not prove causation. An association between A and B may mean that A causes B, B causes A, or both B and A are caused by another factor.
Without detracting from the Nobel prize winning investigation that first drew attention to the role of H pylori, we think that H pylori infection does not cause duodenal ulcer but prevents healing of an ulcer produced by hypersecretion of gastric acid. Acid diminishing treatment reduces the principal barrier against gastric H pylori infection and so the patient becomes infected.
No link with prevalence
If H pylori were the primary cause, we would not see regional variation in the prevalence of duodenal ulcer within areas of high prevalence, particularly developing countries.1 2 3 4 5 This does not refer to Holcombe’s “African enigma,”6 the alleged finding that duodenal ulcer was uncommon in …