Concordance of fluoroquinolone results between GenoType HelicoDR and susceptibility testing for the H. pylori strains included in the phase 2 study

PhenotypeaGenoType HelicoDR result
nMutation allelebWild typec
Strains (n = 92)
    FQ resistant41347d
    FQ susceptible51051
Biopsy specimens (n = 105)
    FQ resistant26242e
    FQ susceptible792f77
Total (n = 197)
    FQ resistant67589
    FQ susceptible1302128
  • a Ciprofloxacin or levofloxacin susceptibility testing using breakpoint of 1 μg/ml. FQ, fluoroquinolone.

  • b One MUT band or no WT band at codon 87 or at codon 91.

  • c Presence of at least one WT band at codons 87 and 91 and no MUT band.

  • d MIC, 32 μg/ml for six strains and 8 μg/ml for one strain.

  • e MIC, 32 μg/ml for the two strains.

  • f MIC < 0.5 μg/ml; silent mutation at codon 88 for one biopsy specimen and absence of wild-type codon 91 for the second.