title: [The epidemiology of clarithromycin resistance of Helicobacter pylori infection in Hungary].
abstract: BACKGROUND
  Antibiotic susceptibility is a major determinant of the eradication treatment outcome and its local determination is recommended in all regions.
  
  
  OBJECTIVE
  The purpose of the study is the assessment of the current prevalence of clarithromycin resistance in our district and an overview of the Hungarian data.
  
  
  METHODS
  A) Biopsy samples were randomly selected from 238 cases examined at the Department of Gastroenterology. The resistance to clarithromycin was determined by fluorescence in situ hybridization. B) Hungarian congress abstracts dealing with resistance to clarithromycin, published between 1995 and 2006, were reviewed and the prevalence and change over time of the resistance was studied. The use of clarithromycin since its introduction in 1993 was analysed.
  
  
  RESULTS
  A) The prevalence of primary clarithromycin resistance was 17.3%. and it was complete in 47.4% and partial in 52.6%. The rate of secondary resistance was of 55.5%. There was a weak positive correlation between age ( r = 0.15), female gender ( r = 0,10) and smoking ( r = 0,16) and prevalence of resistance. B) Clarithromycin resistance was addressed in 8 papers, including 775 cases. The prevalence of resistance determined by phenotypic methods was 3,9%, while fluorescence in situ hybridization detected the resistance in 17.0% of the cases. Regional differences were encountered. Secondary resistance was met in 55.5% using phenotypic and in 49.0% with genotypic methods. C) The use of clarithromycin increased fivefold between 1993-2005.
  
  
  CONCLUSIONS
  The prevalence of clarithromycin resistance determined by genotypic method is increased as compared to the results of earlier phenotypic methods, which could be due to the more extensive use of macrolides.
authors.affiliation: Ferencvárosi Egészségügyi Szolgálat, Gasztroenterológia, Budapest. drgybuzas@hotmail.com
authors.forename: György Miklós
authors.initials: GM
authors.lastname: Buzás
authors.forename: Gábor
authors.initials: G
authors.lastname: Lotz
authors.forename: András
authors.initials: A
authors.lastname: Kiss
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017291:Clarithromycin / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005260:Female; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000453:epidemiology*; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D006814:Hungary / Q000453:epidemiology; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors
chemical_list: D000900:Anti-Bacterial Agents; D017291:Clarithromycin