GP and endoscopist Dr Raghu Raghunath offers hints on testing and eradication
1. Test for Helicobacter pylori in anyone consulting with significant dyspepsia.
In patients who are younger than 55 and presenting with dyspepsia without serious or sinister symptoms, the test and treat strategy is more cost-effective than referral for endoscopy.
2. Stool antigen screening for H. pylori is the most sensitive and specific test for initial detection.
Until recently C13-urea breath test (UBT) was considered to be the gold standard non-invasive test for H. pylori. This is now being replaced by the monoclonal stool antigen test, whose sensitivity and specificity has been reported to be 97% and 96%. It is also cheaper, more accurate and easier than UBT. Check with your local lab about its availability.
3. Routine re-testing for H. pylori to confirm eradication is unnecessary.
Neither the NICE nor the SIGN guidelines advocate routine retesting for H. pylori to confirm eradication.1 But in patients with persistent symptoms after eradication therapy, re-testing and/or referral to a specialist may be appropriate, especially where there is a family history of ulcer disease or gastric cancer.
4. Either UBT or stool antigen test can be used to confirm eradication when the test is needed
UBT is probably preferable to stool antigen test but the difference in their accuracy is minimal. Wait for at least four weeks after eradication therapy before doing the test.
5. Serology testing for H.pylori now has little or no place in primary care.
The specificity quoted in most literature is only 80-85% – much lower than stool antigen testing – meaning some patients will be falsely diagnosed as having an infection and given antibiotics inappropriately.
6. Ensure patients are not on proton pump inhibitors (PPIs) before UBT or stool antigen testing.
H.pylori thrives in the acid environment of the stomach. Acid suppression therefore falsely reduces detection rates. Patients should not have taken PPIs for at least two weeks before either test.
7. PAC (PPI, amoxicillin, clarithromycin) probably has the edge over PCM (PPI, clarithromycin, metronidazole) as an eradication regime.
Evidence for successful eradication is about 80% with either of the above two regimes used for seven days, twice daily. PCM is cheaper than PAC because the dose of clarithromycin used in PCM is 250mg in contrast to 500mg for PAC. But the risk of dual resistance developing to clarithromycin and metronidazole means it is probably better to use PAC as first-line therapy.
8. A course of 14 days increases the eradication rate by another 10% but may not be cost-effective.
In undiagnosed or uninvestigated dyspepsia, the absolute benefit of 14-day therapy as first-line treatment is relatively modest and unlikely to be cost-effective. Despite this, European guidelines still recommend 14-day courses of treatment.2
9. Eradication can be useful in GORD.
The prevalence of H. pylori in patients with GORD is lower than those without GORD, but eradication does not cause or exacerbate symptoms. In patients on long-term PPIs, it is suggested that testing and eradicating those who are positive for H. pylori will have a beneficial effect on the gastric mucosa and may lead to regression of gastric atrophy.
10. Chronic NSAID users might also benefit.
H. pylori eradication is of value in chronic NSAID users but does not completely prevent NSAID-related ulcers. Routine testing for H. pylori is not currently recommended for patients on long-term aspirin.
Dr Raghu Raghunath is a GP and hospital endoscopist in Hull and clinical senior lecturer at Hull York Medical School
Competing interests None declared
Urea breath test for H.pylori Urea breath test for H.pylori