Australians are fortunate that the standard triple therapy for treatment of H.pylori is still largely effective however multi-drug resistant strains are increasing and there is no treatment guideline for managing affected patients.
A research article in Microbiology Australia, co-authored by Professor Barry Marshall, said data from a WA cohort showed more than 20% of H. pylori isolates were triple drug resistant.
“It is believed that this is primarily due to a significant increase of migrants, especially from Asia. According to the 2011 census, 32.8% of Western Australia’s population was born overseas (compared to the National average of 26.1%).”
The article said doctors were relying on experience and “experimenting with different antibiotic combinations” in the face of standard treatment failure.
“This strategy may work for now, but we fear that it will only promote stronger antibiotic resistance in the future.”
Instead, antibiotic susceptibility testing was necessary but hampered by the fact that not every lab was capable of culturing such a fastidious microorganism. As well, endoscopy for collecting a culture specimen was difficult, costly and not available in remote regions.
The authors said alternative antibiotics used in rescue regimens include quinolones, rifampicin, tetracycline and furazolidone. However H. pylori could easily become resistant to quinolones and rifampicin.
“Luckily, resistance to tetracycline, furazolidone, and bismuth compound have not yet been reported.”
They noted that a 2020 study found the addition of bismuth to 14-day standard triple therapy eradicated H. pylori infection in more than 90% of patients.
They also said that resistance to amoxycillin was rare – a statement inconsistent with recent research from Victoria and previously reported in the limbic.
Dr Alfred Tay, Professor Michael Wise and Professor Marshall, from the University of Western Australia, said “around the clock” acid reduction plays a vital role in H. pylori treatment.
“Recently, the potassium competitive acid blocker group (P-CABs) has been used (vonoprazan), which might give a rapid and more complete acid blockade, with subsequent excellent cure rate for H. pylori,” they said.
“New combination therapies show promise and the dream of 100% cure of the infection with minimal side effects from treatment seems achievable. The next decade will see combination therapies with newer acid blockers in widespread use at reasonable cost.”
Dr Tay told the limbic that Japanese research had found the combination of vonoprazan and amoxicillin over seven days was able to achieve above an 80% cure rate
“This is important because amoxicillin is safe for children and pregnant women. So for a long time we are avoiding treatment for children because of the use of strong antibiotics. But it seems possible now with the use of just vonoprazan and amoxicillin,” he said.