title: Helicobacter pylori antibiotic-resistance patterns and risk factors in adult dyspeptic patients from ethnically diverse populations in central and south London during 2000.
abstract: Surveillance of Helicobacter pylori antibiotic susceptibility from patients in London, the largest metropolitan area in the UK, is limited, despite resistance being a key factor in treatment failure. A two-centre survey was performed over 12 months (1999-2000) to determine antibiotic-resistance rates of isolates from dyspeptic patients attending endoscopy clinics serving two ethnically diverse central and south London communities. The in vitro antibiotic susceptibilities were determined from disc diffusion and epsilometer (E) tests on 101 H. pylori isolates. Overall resistance rates were 59% for metronidazole and 11% for clarithromycin, with 8 % resistance to both antibiotics. Corresponding primary resistance rates were 50% and 7%, respectively. High-level-resistance was a feature of 82% of the metronidazole (MIC > or = 256 mg l(-1)) -resistant and 55% of the clarithromycin (MIC > or = 32 mg l(-1)) -resistant strains. All isolates were susceptible to amoxycillin and tetracycline. No associations between resistance and either the gender or the age of the patients were detected. The main risk for resistance to metronidazole was non-UK birth as comparative rates were 68% for non-UK vs. 40% for UK-born individuals. Resistant isolates were genotypically diverse with respect to cagA/vacA type. Four 23S rDNA nucleotide polymorphisms were associated with clarithromycin resistance, mostly (9/11) at A2143G. In conclusion, the high overall metronidazole-resistance rate of 59% for H. pylori from inner London was twice the rate found in other UK-based studies and was attributed to the higher risk of resistant strains infecting individuals born outside the UK. The need for continued resistance surveillance is indicated to monitor the effects of the 'test and treat' strategy for H. pylori eradication, particularly of isolates from at-risk individuals.
authors.affiliation: Laboratory of Enteric Pathogens, Health Protection Agency, Specialist and Reference Microbiology Division, 61 Colindale Avenue, London NW9 5HT, UK 2Food Microbiology Collaborating Unit, Health Protection Agency South West, School of Clinical Veterinary Science, University of Bristol, Churchill Building, Langford, North Somerset BS40 5DU, UK 3HPA Collaborating Centre, Department of Medical Microbiology, St George's Hospital, London SW17 0QT, UK 4HPA Collaborating Centre, Department of Clinical Microbiology, University College London Hospitals, London WC1T 4JF, UK.
authors.forename: Nicola C
authors.initials: NC
authors.lastname: Elviss
authors.affiliation: Laboratory of Enteric Pathogens, Health Protection Agency, Specialist and Reference Microbiology Division, 61 Colindale Avenue, London NW9 5HT, UK 2Food Microbiology Collaborating Unit, Health Protection Agency South West, School of Clinical Veterinary Science, University of Bristol, Churchill Building, Langford, North Somerset BS40 5DU, UK 3HPA Collaborating Centre, Department of Medical Microbiology, St George's Hospital, London SW17 0QT, UK 4HPA Collaborating Centre, Department of Clinical Microbiology, University College London Hospitals, London WC1T 4JF, UK.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Owen
authors.affiliation: Laboratory of Enteric Pathogens, Health Protection Agency, Specialist and Reference Microbiology Division, 61 Colindale Avenue, London NW9 5HT, UK 2Food Microbiology Collaborating Unit, Health Protection Agency South West, School of Clinical Veterinary Science, University of Bristol, Churchill Building, Langford, North Somerset BS40 5DU, UK 3HPA Collaborating Centre, Department of Medical Microbiology, St George's Hospital, London SW17 0QT, UK 4HPA Collaborating Centre, Department of Clinical Microbiology, University College London Hospitals, London WC1T 4JF, UK.
authors.forename: Aodhan
authors.initials: A
authors.lastname: Breathnach
authors.affiliation: Laboratory of Enteric Pathogens, Health Protection Agency, Specialist and Reference Microbiology Division, 61 Colindale Avenue, London NW9 5HT, UK 2Food Microbiology Collaborating Unit, Health Protection Agency South West, School of Clinical Veterinary Science, University of Bristol, Churchill Building, Langford, North Somerset BS40 5DU, UK 3HPA Collaborating Centre, Department of Medical Microbiology, St George's Hospital, London SW17 0QT, UK 4HPA Collaborating Centre, Department of Clinical Microbiology, University College London Hospitals, London WC1T 4JF, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Palmer
authors.affiliation: Laboratory of Enteric Pathogens, Health Protection Agency, Specialist and Reference Microbiology Division, 61 Colindale Avenue, London NW9 5HT, UK 2Food Microbiology Collaborating Unit, Health Protection Agency South West, School of Clinical Veterinary Science, University of Bristol, Churchill Building, Langford, North Somerset BS40 5DU, UK 3HPA Collaborating Centre, Department of Medical Microbiology, St George's Hospital, London SW17 0QT, UK 4HPA Collaborating Centre, Department of Clinical Microbiology, University College London Hospitals, London WC1T 4JF, UK.
authors.forename: Nandini
authors.initials: N
authors.lastname: Shetty
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D017291:Clarithromycin / Q000494:pharmacology*; D004351:Drug Resistance / Q000235:genetics*; D004415:Dyspepsia / Q000453:epidemiology / Q000208:ethnology / Q000382:microbiology*; D004641:Emigration and Immigration; D005260:Female; D016481:Helicobacter Infections / Q000453:epidemiology / Q000208:ethnology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D006761:Hospitals; D006801:Humans; D008131:London / Q000453:epidemiology; D008297:Male; D008795:Metronidazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012329:RNA, Bacterial / Q000235:genetics; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D012307:Risk Factors
chemical_list: D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012338:RNA, Ribosomal, 23S; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori; D008795:Metronidazole; D017291:Clarithromycin