title: Dual-priming oligonucleotide-based multiplex PCR for the detection of Helicobacter pylori and determination of clarithromycin resistance with gastric biopsy specimens.
abstract: BACKGROUND
  Assessment of Helicobacter pylori (H. pylori) clarithromycin resistance has rarely been performed routinely despite an increasing resistance rate. Our aim was to develop and evaluate the use of dual-priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) to detect point mutations in the 23S rRNA gene responsible for clarithromycin resistance of H. pylori.
  
  
  METHODS
  Gastric biopsy specimens from 212 untreated patients with dyspepsia were examined by culture, histology, and DPO-based multiplex PCR. A disk diffusion test and E-test were used for performing phenotypic antibiotic susceptibility tests.
  
  
  RESULTS
  Among the biopsy specimens tested, 22.2% (47/212), 42.5% (90/212), and 41.5% (88/212) of the specimens were classified as H. pylori positive by culture, histology, and DPO-based multiplex PCR, respectively. Among 96 strains identified by either culture or DPO-based multiplex PCR, 80 strains were clarithromycin-susceptible and 16 strains (16.7%) were clarithromycin-resistant. There was 94.1% (32/34) concordance between phenotypic susceptibility tests and DPO-based multiplex PCR. In two patients with discrepant results, only DPO-based multiplex PCR detected clarithromycin-resistant strains. DPO-based multiplex PCR identified additional 49 clarithromycin-resistant or clarithromycin-susceptible H. pylori among 165 culture-negative specimens.
  
  
  CONCLUSIONS
  DPO-based multiplex PCR can be used as a practical method for the detection of H. pylori infection and the determination of clarithromycin susceptibility in addition to phenotypic antimicrobial susceptibility tests.
authors.affiliation: Department of Laboratory Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: Hee-Yeon
authors.initials: HY
authors.lastname: Woo
authors.forename: Dong Il
authors.initials: DI
authors.lastname: Park
authors.forename: Hyosoon
authors.initials: H
authors.lastname: Park
authors.forename: Min-Kyung
authors.initials: MK
authors.lastname: Kim
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Kim
authors.forename: In-Suk
authors.initials: IS
authors.lastname: Kim
authors.forename: Young Jae
authors.initials: YJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001706:Biopsy; D017291:Clarithromycin / Q000494:pharmacology*; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D024881:Drug Resistance, Bacterial; D005260:Female; D016481:Helicobacter Infections / Q000382:microbiology* / Q000473:pathology; D016480:Helicobacter pylori / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction / Q000379:methods*; D012338:RNA, Ribosomal, 23S / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D017931:DNA Primers; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012338:RNA, Ribosomal, 23S; D017291:Clarithromycin