Helicobacter Pylori

by Advanced GI WA

Helicobactor pylori is present in approximately 30% of adult Australians but is not uniformly distributed in the population. The prevalence of infection is higher in older people, migrants, those with lower socio-economic status and the institutionalised.

Most people with infections of H pylori are asymptomatic but infection conveys a lifetime risk of peptic ulcer disease of 15-20% and of gastric cancer of up to 2%. While everyone develops an active chronic gastritis, there is an inconsistent relationship between the presence of H pylori gastritis and symptoms. H pylori is directly implicated in causing both gastric and duodenal ulcers, eradication in these patients leads to long term remission of their symptoms. In contrast only a minority of people with H pylori gastritis without peptic ulcer disease and who have symptoms of non ulcer dyspepsia will get sustained relief of their symptoms after eradication therapy.

Indications to treat are:

• Peptic ulcer disease, past or present
• NSAID and aspirin users
• First degree relatives of patients with gastric cancer
• Low grade gastric MALT lymphoma
• Dyspepsia
• Atrophic gastritis and intestinal metaplasia
• Patients requiring long term acid suppression
• Patients with treated early gastric cancer

Eradication of H pylori

Therapy:

1. Esomeprazole 20 mgs BD x 7 days
   Plus
2. Amoxicillin 1 gm BD x 7 days
   Plus
3. Clarithromycin 500g BD. x 7 days

This regime did achieve success rates of 85-90% in clinical trials initially but there is an increasing incidence of clarithromycin resistance and now the success rate of eradication with this regime may be closer to 60-70%. If this regime fails then a repeat course has a less than 10% chance of being effective and should not be used. Side effects including taste disturbance, nausea and diarrhoea are common. Eradication rates are strongly related to compliance, i.e. if the patient misses tablets then eradication rates are reduced significantly.

Eradication therapy in penicillin hypersensitive

1. Standard dose PPI BD x 7 days
   Plus
2. Metronidazole 400mg BD x 7 days
   Plus
3. Clarithromycin 500 mgs BD x 7 days

Failure of eradication therapy

Clarithromycin resistance is very common and the incidence increases after failure of first line therapy. Repeat treatment with a clarithromycin containing combination has a very low rate of success and should be avoided.

There are a range of regimens available for second line or 'salvage' therapy. These are constantly changing and referral to a specialist with an interest in this area is preferable to repeated efforts with combinations that are unlikely to be effective. Sequential regimes and quadruple therapy regimes can be used in this situation.

Referral for endoscopy with biopsies taken for culture and testing for antibiotic sensitivity may be appropriate. It is important that prior to any testing no antibiotics should be taken for at least one month and PPIs should be suspended for one week at least and two weeks if possible to minimise the chance of false negative results. There is considerable variation in laboratories experience and ideally a laboratory with a track record of successfully culturing H pylori should be employed.