ArticleAnnals of tropical medicine and parasitology2011
Characterisation of the genes encoding resistance to metronidazole (rdxA and frxA) and clarithromycin (the 23S-rRNA genes) in South African isolates of Helicobacter pylori.
Article in Annals of tropical medicine and parasitology, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers, 3 of them syntheses that pooled it.
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Who cites it
17 citing papers in PubMed, 3 syntheses or guidelines pooled it, 23 citations in OpenAlex.
- Clarithromycin-resistant Helicobacter pylori in Africa: a systematic review and meta-analysis.Antimicrobial resistance and infection control · 2025Pooled it
- The prevalence of clarithromycin-resistantPeerJ · 2023Pooled it
- The magnitude of antibiotic resistance to Helicobacter pylori in Africa and identified mutations which confer resistance to antibiotics: systematic review and meta-analysis.BMC infectious diseases · 2018Pooled it
- Multiplex fluorescent PCR-based detection of Helicobacter pylori nucleic acid and antibiotic resistance genes in clinical stool samples: a performance evaluation from Gansu Province, China.BMC infectious diseases · 2026Article
- Antibiotic resistance in Helicobacter pylori: a genetic and physiological perspective.Gut pathogens · 2025Review
- Detection ofCurrent issues in molecular biology · 2025Article
- Analysis of antibiotic susceptibility and genomic characteristics of Helicobacter pylori by whole-genome resequencing in Northern China.Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology] · 2025Article
- Prevalence of Clarithromycin-Resistant Helicobacter pylori Strains in Zambia: A Sub-Saharan African Country.Digestive diseases (Basel, Switzerland) · 2024Article
- Helicobacter pylori Infection, Its Laboratory Diagnosis, and Antimicrobial Resistance: a Perspective of Clinical Relevance.Clinical microbiology reviews · 2022Review
- Phenotypic and Genotypic Analysis of ResistantDiagnostics (Basel, Switzerland) · 2020Article
- Helicobacter pylori Infections in the Bronx, New York: Surveying Antibiotic Susceptibility and Strain Lineage by Whole-Genome Sequencing.Journal of clinical microbiology · 2020Article
- Mutations in the Antibiotic Target Genes Related to Clarithromycin, Metronidazole and Levofloxacin Resistance inInfection and drug resistance · 2020Article
- Current understanding and management ofF1000Research · 2018Review
- Systematic review in South Africa reveals antibiotic resistance genes shared between clinical and environmental settings.Infection and drug resistance · 2018Review
- Oxidative and nitrosative stress defences of Helicobacter and Campylobacter species that counteract mammalian immunity.FEMS microbiology reviews · 2016Article
- Article
- Phenotypic and transcriptional profiling in Entamoeba histolytica reveal costs to fitness and adaptive responses associated with metronidazole resistance.Frontiers in microbiology · 2015Article
Corrections and comments
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Authors and funding
3 authors at 1 institution in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Helicobacter pylori has been incriminated in human diseases, such as peptic ulcer, gastritis and gastric malignancy. Although modern triple-drug regimens are usually highly effective in the treatment of H. pylori infection, the emergence of resistance to two of the most used antibiotics, metronidazole (Mtz) and clarithromycin (Cla), is a serious and increasing problem. Truncations in the rdxA and frxA genes of H. pylori are thought to be associated with Mtz resistance whereas mutations in the pathogen's 23S-ribosomal-RNA (23S-rRNA) genes are associated with Cla resistance. In a recent study, PCR and sequence analysis of the rdxA, frxA and 23S-rRNA genes were used to explore the genetic basis of resistance to Mtz and Cla in H. pylori. When 200 isolates of H. pylori from the Eastern Cape province of South Africa were tested for antibiotic susceptibility, almost all (95·5%) were found resistant to Mtz and 20·0% were found resistant to Cla. Only the Mtz-resistant isolates showed rdxA and frxA truncation. Two point mutations were detected in the 23S-rRNA genes of the Cla-resistant isolates. Many significant changes (resulting in 13 amino-acid substitutions in nine loci and truncated proteins in 14 loci) were observed in the rdxA genes of the Mtz-resistant isolates, and it appears that, compared with the rarer changes detected in frxA, such mutations may contribute more significantly to the high prevalence of Mtz resistance. To guide empiric treatment, the genotypes and antibiotic susceptibility of H. pylori in the Eastern Cape province of South Africa need to be monitored regularly.
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