title: Ultimate eradication rate of Helicobacter pylori after first, second, or third-line therapy in Korea.
abstract: OBJECTIVE
  Resistance rates of Helicobacter pylori to clarithromycin, metronidazole, and quinolone are over 30% in South Korea. The aim of this prospective study was to evaluate the ultimate eradication rate of H. pylori after first, second, or third-line therapy in Korea.
  
  
  METHODS
  A cohort of 2202 patients with H. pylori was treated with proton pump inhibitor (PPI)-based triple therapy for seven days. In case of treatment failure or recurrence, moxifloxacin-based triple therapy (MA) or bismuth-based quadruple therapy (QUAD) was randomly given. When the second-line treatment failed or H. pylori recurred, the unused MA or QUAD was used as a third-line treatment.
  
  
  RESULTS
  Eighty-six patients had recurrence at least once during consecutive lines of treatments. Among 2116 patients (intention-to-treat [ITT]) without recurrence, 1644 (77.7%, per-protocol [PP]) completely followed our treatment flow. The ITT and PP rates of first-line treatment were 69.8% and 89.3%. After second line, they reached 78.4% (ITT) and 98.4% (PP). The "final" eradication rate up to third line treatment were 80.0% (1692/2116) and 99.8% (1641/1644), respectively. Resistance to clarithromycin showed significantly lower eradication rate (OR 0.358, P < 0.001) than those with susceptible strains in multivariate analysis. However in PP analysis, there was no significant difference in ultimate success rate regarding resistance pattern.
  
  
  CONCLUSIONS
  Final success rate of PP was high, 99.8% in Korea in spite of high antibiotic resistance rates. However, high rate of refusal of further treatment and follow-up loss made ITT eradication rate low. Proper strategy to improve the treatment adherence is needed.
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Kichul
authors.initials: K
authors.lastname: Yoon
authors.forename: Nayoung
authors.initials: N
authors.lastname: Kim
authors.forename: Ryoung H
authors.initials: RH
authors.lastname: Nam
authors.forename: Ji H
authors.initials: JH
authors.lastname: Suh
authors.forename: Seonmin
authors.initials: S
authors.lastname: Lee
authors.forename: Jung M
authors.initials: JM
authors.lastname: Kim
authors.forename: Ju Y
authors.initials: JY
authors.lastname: Lee
authors.forename: Yong H
authors.initials: YH
authors.lastname: Kwon
authors.forename: Yoon J
authors.initials: YJ
authors.lastname: Choi
authors.forename: Hyuk
authors.initials: H
authors.lastname: Yoon
authors.forename: Cheol M
authors.initials: CM
authors.lastname: Shin
authors.forename: Young S
authors.initials: YS
authors.lastname: Park
authors.forename: Dong H
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000658:Amoxicillin / Q000008:administration & dosage; D017291:Clarithromycin / Q000008:administration & dosage; D015331:Cohort Studies; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination; D005260:Female; D005756:Gastritis / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology*; D016481:Helicobacter Infections; D016480:Helicobacter pylori; D006801:Humans; D007723:Korea / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance / Q000706:statistics & numerical data; D054328:Proton Pump Inhibitors / Q000008:administration & dosage; D012008:Recurrence; D016896:Treatment Outcome
chemical_list: D054328:Proton Pump Inhibitors; D000658:Amoxicillin; D017291:Clarithromycin
keywords: Helicobacter pylori; antibiotic resistance; eradication