title: Surveillance of Levofloxacin Resistance in Helicobacter pylori Isolates in Bogotá-Colombia (2009-2014).
abstract: Increased resistance of Helicobacter pylori to clarithromycin and metronidazole has resulted in recommendation to substitute fluoroquinolones for eradication therapy. The aims of the study were to determine the prevalence and changes in primary levofloxacin resistance related to H. pylori gyrA sequences. The study utilized H. pylori strains isolated from patients undergoing gastroscopy in Bogotá, Colombia from 2009 to 2014. Levofloxacin susceptibility was assessed by agar dilution. Mutations in gyrA sequences affecting the quinolone resistance-determining region (QRDR) were evaluated by direct sequencing. Overall, the mean prevalence of primary levofloxacin resistance was 18.2% (80 of 439 samples). Resistance increased from 11.8% (12/102) in 2009 to 27.3% (21/77) in 2014 (p = 0.001). gyrA mutations in levofloxacin resistant strains were present in QRDR positions 87 and 91. The most common mutation was N87I (43.8%, 35/80) followed by D91N (28.8%, 23/80) and N87K (11.3%, 9/80). Levofloxacin resistance increased markedly in Colombia during the six-year study period. Primary levofloxacin resistance was most often mediated by point mutations in gyrA, with N87I being the most common QRDR mutation related to levofloxacin resistance.
authors.affiliation: Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Pontificia Universidad Javeriana, Bogotá, D.C, Colombia.
authors.forename: Alba A
authors.initials: AA
authors.lastname: Trespalacios-Rangél
authors.affiliation: Unidad de Gastroenterología, Universidad Nacional de Colombia, Bogotá, D.C, Colombia.
authors.forename: William
authors.initials: W
authors.lastname: Otero
authors.affiliation: Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Pontificia Universidad Javeriana, Bogotá, D.C, Colombia.
authors.forename: Azucena
authors.initials: A
authors.lastname: Arévalo-Galvis
authors.affiliation: Grupo de Biotecnología Ambiental e Industrial (GBAI). Departamento de Microbiología, Pontificia Universidad Javeriana, Bogotá, D.C, Colombia.
authors.forename: Raúl A
authors.initials: RA
authors.lastname: Poutou-Piñales
authors.affiliation: Department of Medicine, Michael E. DeBakey Veterans Affairs Medical Center, Houston TX, United States of America.|Baylor College of Medicine, Houston TX, United States of America.
authors.forename: Emiko
authors.initials: E
authors.lastname: Rimbara
authors.affiliation: Department of Medicine, Michael E. DeBakey Veterans Affairs Medical Center, Houston TX, United States of America.|Baylor College of Medicine, Houston TX, United States of America.
authors.forename: David Y
authors.initials: DY
authors.lastname: Graham
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003105:Colombia / Q000453:epidemiology; D027081:DNA Gyrase / Q000235:genetics; D024881:Drug Resistance, Bacterial; D005260:Female; D016481:Helicobacter Infections / Q000453:epidemiology* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D064704:Levofloxacin / Q000494:pharmacology*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009154:Mutation; D015995:Prevalence; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D064704:Levofloxacin; D027081:DNA Gyrase