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Gastric Mucosa Quantitative Polymerase Chain Reaction Analysis for Detecting Helicobacter pylori and Antibiotic Resistance
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Antibiotic-resistant Helicobacter pylori strains in Portuguese children

Ana Isabel Lopes1, Mónica Oleastro, Ana Palha

  • 1Unit of Pediatric Gastroenterology and Nutrition, Department of Pediatrics, INSA, Lisbon, Portugal. rop85873@mail.telepac.pt

The Pediatric Infectious Disease Journal
|May 7, 2005
PubMed

Insights

High antibiotic resistance in pediatric Helicobacter pylori strains was observed. Susceptibility-based treatment showed a modest eradication rate, highlighting the need for further studies and surveillance.

Area of Science:

  • Pediatric infectious diseases
  • Microbiology
  • Clinical pharmacology

Background:

  • Limited data exists on the effectiveness of Helicobacter pylori (H. pylori) eradication regimens guided by antibiotic susceptibility testing in children.
  • Antibiotic resistance in H. pylori poses a significant challenge to effective treatment in pediatric populations.

Purpose of the Study:

  • To determine the prevalence of antibiotic resistance in H. pylori strains from Portuguese children (1999-2003).
  • To assess the eradication rate of H. pylori using treatments tailored by antibiotic susceptibility testing.
  • To identify factors linked to antibiotic resistance and treatment outcomes in children.

Main Methods:

  • Analysis of H. pylori strains from gastric biopsies of 109 children.
  • Antibiotic susceptibility testing (E test) to guide first-line treatment with amoxicillin, omeprazole, and either clarithromycin or metronidazole.
  • Eradication assessment using the [C]urea breath test.

Main Results:

  • High resistance rates were found: 39.4% to clarithromycin, 16.5% to metronidazole, and 4.5% to ciprofloxacin. Strains remained susceptible to amoxicillin and tetracycline.
  • Clarithromycin resistance was associated with European origin, prior H. pylori empiric therapy, and amoxicillin minimal inhibitory concentration.
  • The susceptibility-based treatment achieved a 74.7% eradication rate, with failure linked to resistance to one or more antibiotics.

Conclusions:

  • The study revealed a high prevalence of H. pylori antibiotic resistance in the pediatric cohort.
  • The moderate success of susceptibility-guided clarithromycin and metronidazole regimens suggests other factors influence treatment outcomes.
  • Emphasizes the necessity for susceptibility-based treatment studies in children and ongoing antimicrobial resistance surveillance for H. pylori.
Abstract

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