title: Primary resistance of Helicobacter pylori is still low in Southern Austria.
abstract: OBJECTIVE
  We determined primary and secondary resistance rates of H. pylori in different regions of Austria and potential bacterial and host factors associated with resistance.
  
  
  METHODS
  In a prospective multicentre study H. pylori was cultivated from biopsies and susceptibility testing was performed according to EUCAST. Resistance to clarithromycin and levofloxacin was determined by sequencing of the resistance-determining regions of 23S rRNA and gyrA genes. cagA, vacA and babA2 genotypes were determined.
  
  
  RESULTS
  A total of 1266 patients were included. 178 isolates were cultured: 128 from patients without prior eradication therapy, 50 from patients after failed eradication. Primary resistance to clarithromycin, levofloxacin and metronidazole were 17.2%, 9.4% and 10.2%, respectively. Secondary resistance to clarithromycin, levofloxacin and metronidazole were 64%, 18% and 44%, respectively. Prior eradication was associated with a higher risk of clarithromycin as well as metronidazole resistance (OR=8.1; 95% CI 3.8-17.1 and OR 5.7; 95% CI 2.5-13, respectively).
  
  
  CONCLUSIONS
  Primary resistance to both clarithromycin and levofloxacin was markedly lower in Southern Austria than recently reported.
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Medical University of Graz, Austria. Electronic address: ines.schwetz@medunigraz.at.
authors.forename: Ines
authors.initials: I
authors.lastname: Zollner-Schwetz
authors.affiliation: Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Leitner
authors.affiliation: Department of Internal Medicine, Barmherzige Brüder Krankenhaus St. Veit/Glan, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Plieschnegger
authors.affiliation: MedCenter Judenburg, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Semlitsch
authors.affiliation: Department of Internal Medicine, Krankenhaus der Elisabethinen, Graz, Austria.
authors.forename: Vinzenz
authors.initials: V
authors.lastname: Stepan
authors.affiliation: Department of Internal Medicine, Brothers of St. John of God Hospital, Graz, Austria.
authors.forename: Lukas
authors.initials: L
authors.lastname: Reiter
authors.affiliation: Department of Internal Medicine, Brothers of St. John of God Hospital, Graz, Austria.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Reicht
authors.affiliation: Lassnitzhöhe, Austria.
authors.forename: Eduard
authors.initials: E
authors.lastname: Mörth
authors.affiliation: Weiz, Austria.
authors.forename: Jörg
authors.initials: J
authors.lastname: Pavek
authors.affiliation: Kapfenberg, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Parsché
authors.affiliation: Department of Internal Medicine, Landeskrankenhaus Rottenmann, Rottenmann, Austria.
authors.forename: Christina
authors.initials: C
authors.lastname: Betterklieber
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Medical University of Graz, Austria.
authors.forename: Denise
authors.initials: D
authors.lastname: Atzmüller
authors.affiliation: Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Medical University of Graz, Austria.
authors.forename: Robert
authors.initials: R
authors.lastname: Krause
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine, Medical University of Graz, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Högenauer
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001317:Austria / Q000453:epidemiology; D017291:Clarithromycin / Q000494:pharmacology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D005260:Female; D005838:Genotype; D016481:Helicobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D064704:Levofloxacin / Q000494:pharmacology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D017422:Sequence Analysis, DNA; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012338:RNA, Ribosomal, 23S; D037521:Virulence Factors; D064704:Levofloxacin; D017291:Clarithromycin
keywords: Clarithromycin resistance; Helicobacter pylori; Mutations 23S rRNA; Primary resistance; Virulence factors