title: Primary antibiotic resistance of Helicobacter pylori strains isolated from patients with dyspeptic symptoms in Beijing: a prospective serial study.
abstract: OBJECTIVE
  To determine the resistance patterns of Helicobacter pylori (H. pylori) strains isolated from patients in Beijing and monitor the change of antibiotic resistance over time.
  
  
  METHODS
  In this prospective, serial and cross-sectional study, H. pylori cultures were successfully obtained from 371 and 950 patients (never receiving eradication) during 2009-2010 and 2013-2014, respectively. Resistance to amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and rifampicin was determined by Epsilometer test.
  
  
  RESULTS
  The resistance rates of isolates obtained during 2009-2010 were 66.8%, 39.9%, 34.5%, 15.4%, 6.7%, and 4.9% to metronidazole, clarithromycin, levofloxacin, rifampicin, amoxicillin and tetracycline, respectively; and the corresponding rates for isolates during 2013-2014 were 63.4%, 52.6%, 54.8%, 18.2%, 4.4% and 7.3%, respectively. The resistance rates to clarithromycin and levofloxacin were significantly increased after four years. In 2009-2010, 14.6% of H. pylori isolates were susceptible to all tested antibiotics, with mono (33.7%), double (28.3%), triple (16.7%), quadruple (6.2%), quintuple (0.3%) and sextuple resistance (0.3%) also being detected. In 2013-2014, 9.4% were susceptible to all tested antibiotics, and mono (27.6%), double (28.4%), triple (24.9%), quadruple (7.3%), quintuple (2.3%) and sextuple resistance (0.1%) was also observed. More multiple resistant H. pylori isolates were found during 2013-2014. Gender (to levofloxacin and metronidazole), age (to levofloxacin) and endoscopic findings (to clarithromycin) were independent factors influencing antibiotic resistance.
  
  
  CONCLUSIONS
  H. pylori resistance to commonly used antibiotics in Beijing is high with increased multiple antibiotic resistance.
authors.affiliation: Yue-Xi Zhang, Department of Gastroenterology, Beijing Sixth Hospital, Beijing 100007, China.
authors.forename: Yue-Xi
authors.initials: YX
authors.lastname: Zhang
authors.affiliation: Yue-Xi Zhang, Department of Gastroenterology, Beijing Sixth Hospital, Beijing 100007, China.
authors.forename: Li-Ya
authors.initials: LY
authors.lastname: Zhou
authors.affiliation: Yue-Xi Zhang, Department of Gastroenterology, Beijing Sixth Hospital, Beijing 100007, China.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Song
authors.affiliation: Yue-Xi Zhang, Department of Gastroenterology, Beijing Sixth Hospital, Beijing 100007, China.
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Zhang
authors.affiliation: Yue-Xi Zhang, Department of Gastroenterology, Beijing Sixth Hospital, Beijing 100007, China.
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: He
authors.affiliation: Yue-Xi Zhang, Department of Gastroenterology, Beijing Sixth Hospital, Beijing 100007, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ding
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001706:Biopsy; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D024881:Drug Resistance, Bacterial; D004415:Dyspepsia / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology*; D005753:Gastric Mucosa / Q000382:microbiology*; D016481:Helicobacter Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents
keywords: Antibiotic resistance; Beijing; Dyspeptic symptoms; Helicobacter pylori