Open AccessSurveillance of Levofloxacin Resistance in Helicobacter pylori Isolates in Bogotá-Colombia (2009-2014)
Author(s) -
Alba Alicia Trespalacios-Rangel,
William Otero,
Azucena Arévalo-Galvis,
Raúl A. Poutou-Piñales,
Emiko Rimbara,
David Y. Graham
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0160007
Subject(s) - levofloxacin , helicobacter pylori , clarithromycin , microbiology and biotechnology , medicine , agar dilution , quinolone , antibiotic resistance , metronidazole , drug resistance , ofloxacin , ciprofloxacin , point mutation , antibiotics , biology , minimum inhibitory concentration , mutation , genetics , gene
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 gyr A 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 gyr A 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). gyr A 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 gyr A, with N87I being the most common QRDR mutation related to levofloxacin resistance.