Helicobacter Pylori: The Organism, the Disease, the Clinical Picture, the Current Research
In infected patients, 30%-35% have no symptoms.
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.
At that time when Warren and Marshall announced their findings, it was a long-standing belief in medical teaching and practice that stress and lifestyle factors were the major causes of peptic ulcer disease. Warren and Marshall rebutted that dogma, and it was soon clear that H. pylori, causes more than 90% of duodenal ulcers and up to 80% of gastric ulcers (Graham DY., 1999). The clinical community, however, met their findings, with skepticism and a lot of criticism and that's why it took quite a remarkable length of time for their discovery to become widely accepted. They had to just push it harder and harder with all experimental and clinical evidences. In 1985, for example, Marshall underwent gastric biopsy to put evidence that he didn't carry the bacterium, then deliberately infected himself to show that it in fact caused acute gastric illness. 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).
Bacterial culture from the gastric biopsy is the gold standard technique, and is recommended for antibiotic susceptibility test. Serology is used for initial screening and the stool antigen test is particularly used when the urea breath test is not available, while molecular methods have gained attention mostly for detecting antibiotic resistance.
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