What it is and why it matters
Helicobacter pylori is a bacterium that colonises the stomach. Around half the world's population is thought to carry it, and most infected people notice nothing at all.
When it does cause trouble, it produces chronic gastritis and can lead to stomach or duodenal ulcers. It is also the most important preventable risk factor for stomach cancer, which is why it is treated whenever it is found.
When it should be looked for and treated
- Current or past stomach or duodenal ulcer
- Persistent discomfort in the upper abdomen
- First-degree relatives with stomach cancer
- Gastric MALT lymphoma
- Iron deficiency anaemia or vitamin B12 deficiency with no other explanation
- Before starting long-term anti-inflammatory or aspirin treatment
- Precursor lesions on a previous gastroscopy: atrophy or intestinal metaplasia
Why treatment fails
In Spain, resistance to some antibiotics, particularly clarithromycin and levofloxacin, is high. That explains a good share of failures, but not all of them.
- Resistance of the bacterium to the antibiotics used
- Courses that are too short or underdosed
- Treatment abandoned because of side effects, which are common
- Having taken those same antibiotics previously for other reasons
- A poorly performed test of cure, which makes it look as though treatment failed when it did not
Repeating the same course almost never works
If a course has failed to eradicate the bacterium, persisting with the same antibiotics has little chance of success. The second attempt must be chosen on the basis of what you have already taken.
How I approach it
- We review exactly what you have takenWhich antibiotics, at what dose and for how many days. This determines everything else, and patients often don't have the information because nobody has asked for it.
- We check how the result was confirmedThe breath test must be done at least four weeks after finishing antibiotics, with the proton pump inhibitor stopped two weeks beforehand. Otherwise the result is not reliable.
- We choose the right rescue therapyThere are several second- and third-line regimens. The choice depends on the antibiotics already used and on your allergies.
- In refractory cases, resistance testingWhen two or more courses have failed, I perform a gastroscopy with sampling for culture and sensitivity, or molecular resistance testing, and target treatment on that result.
- We confirm eradicationAlways. Treatment without a test of cure is only half a treatment.
My work in this area
I took part as an investigator in a project on the genetic and environmental factors associated with progression of precursor lesions of gastric cancer, with results published in the International Journal of Cancer. That is the perspective I bring when deciding whether atrophic gastritis or metaplasia needs surveillance, and how often.