How to treat Helicobacter pylori? Understanding how to choose the first-line scheme

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The Helicobacter pylori (H. pylori) is the most prevalent chronic bacterial infection in the world, affecting more than half of the population. It is associated with chronic gastritis, which can progress to serious complications such as peptic ulcer, adenocarcinoma, and MALT lymphoma.

Based on current evidence, its eradication has been more broadly recommended, even in the absence of symptoms in many situations. The main references that guide the conduct of H. pylori in Brazil are:

• IV Brazilian Consensus (2018)
• Maastricht VI / Florence Consensus (2022)

One of the most important causes of failure to eradicate H. pylori is the increase in resistance to clarithromycin and levofloxacin. Resistance to nitroimidazoles is also common. On the other hand, resistance to amoxicillin and tetracycline is low and stable. These concepts are important both when we think about first-line schemes and retreatment schemes.

The choice of the initial treatment scheme for H pylori considers two main aspects:

• Local rate of resistance to clarithromycin
• History of drug allergy

It would be interesting to perform a susceptibility test (molecular or culture) before prescribing antibiotics, but we know that these methods are still extremely scarce (or even almost non-existent) in our daily Brazilian practice.

In areas where there is low resistance to clarithromycin (< 15%), the first-line empirical treatment should be triple therapy with clarithromycin or quadruple therapy with bismuth. A few studies have evaluated the resistance profile of H. pylori in Brazil, identifying resistance of 2.5 to 16.9% to clarithromycin, 5 to 23% to fluoroquinolones, approximately 50% to metronidazole and double resistance to clarithromycin and metronidazole from 7.5 to 10%. Given this, the trend of the Brazilian Consensus is still to consider Brazil as a low resistance area to clarithromycin.

Since Maastricht V (2017) and the IV Brazilian Consensus (2018), an important change in treatment recommendations for H. pylori was the increase in duration from 7 to 14 days in an attempt to increase the eradication rate in the face of the growing increase in bacterial resistance.

The first-line schemes proposed in our country, therefore, are the following:

• Recommended scheme: OAC – Standard triple therapy with clarithromycin

• Alternative scheme: BOTM – Quadruple therapy with bismuth

• Another alternative scheme: OACM – Concomitant quadruple therapy without bismuth. It is an option in areas of higher proven resistance to clarithromycin when bismuth is not available.

Speaking of the availability of colloidal bismuth subcitrate, this medication has been very little available in our country. Currently, it can only be obtained through compounding (and even then with some difficulty). This reminds us of furazolidone, which has been widely used in schemes for the treatment of H. pylori, but which has not been marketed for years in our country.

Penicillin allergy

The eradication of H. pylori in patients with penicillin allergy (reported in up to 3 to 10% of people) is a challenge. Ideally, this allergy should really be proven to have the schemes with amoxicillin available.

According to the Brazilian Consensus, there are two main schemes:

• Triple therapy with levofloxacin in substitution for amoxicillin (OCL)
• Quadruple therapy with bismuth (BOTM), as previously mentioned

Adverse effects

Unfortunately, up to 50% of patients experience side effects with H. pylori treatment. In less than 10%, these effects are limiting and lead to therapy interruption. It is therefore always important to properly inform patients about the most common side effects to increase adherence:

• Amoxicillin: Diarrhea, skin rash
• Clarithromycin: Nausea, vomiting, abdominal pain, metallic taste, rarely QT prolongation

Do probiotics help?

Probiotics (such as Lactobacilli and Saccharomyces boulardii) reduce the side effects associated with eradication therapy and, with this, can increase adherence. There are studies on direct effects on H. pylori, but more data are still needed.

It is necessary to check curability? When?

Yes. It should be performed at least 4 weeks after treatment. Ideally, non-invasive methods should be preferred, reserving endoscopy only if indicated for another reason (e.g., gastric ulcer cure control).

Conclusion

The H. pylori is extremely common and its eradication can often be a challenge. The standard triple therapy (OAC) in Brazil provides cure rates above 80% and is still the most used. However, we must be aware of the growing levels of bacterial resistance to constantly update our recommendations.

How to cite this article

Lages RB. How to treat Helicobacter pylori? Understanding how to choose the first-line scheme. Gastropedia 2022. Available at https://gastropedia.pub/en/gastroenterology/how-to-treat-helicobacter-pylori-understanding-how-to-choose-the-first-line-scheme

References

[1] Malfertheiner P, Megraud F, Rokkas T, Gisbert JP, Liou JM, Schulz C, et al. Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report. Gut 2022;71:1724–62. doi:10.1136/gutjnl-2022-327745.
[2] Coelho LGV, Marinho JR, Genta R, Ribeiro LT, Passos M CF, Zaterka S, et al. IVth Brazilian Consensus Conference on Helicobacter pylori infection. Arq Gastroenterol 2018;55:97–121. doi:10.1590/s0004-2803.201800000-20.