Clarithromycin-susceptible and -resistant Helicobacter pylori isolates with identical randomly amplified polymorphic DNA-PCR genotypes cultured from single gastric biopsy specimens prior to antibiotic therapy.
Of the Helicobacter pylori populations from 976 patients, six contained clarithromycin-resistant as well as -susceptible colonies. In each heterogeneous H. pylori population, resistant H. pylori colonies harbored identical 23S ribosomal DNA (rDNA) mutations associated with clarithromycin resistance, while the susceptible H. pylori colonies all had wild-type 23S rDNA. The resistant and susceptible colonies of each of the heterogeneous H. pylori populations had identical randomly amplified polymorphic DNA-PCR genotypes. In conclusion, evaluation of antimicrobial susceptibility can be misinterpreted if only a single colony from the primary H. pylori population is used to test for clarithromycin susceptibility.
van der Ende
A
A
Departments of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. a.vanderende@amc.uva.nl
van Doorn
L J
LJ
Rooijakkers
S
S
Feller
M
M
Tytgat
G N
GN
Dankert
J
J
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017291:Clarithromycin / Q000494:pharmacology*; D003470:Culture Media; D004275:DNA, Ribosomal / Q000032:analysis; D004352:Drug Resistance, Microbial; D016099:Endoscopy, Gastrointestinal; D005838:Genotype; D016481:Helicobacter Infections / Q000382:microbiology; D016480:Helicobacter pylori / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests; D009154:Mutation; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D019105:Random Amplified Polymorphic DNA Technique
D000900:Anti-Bacterial Agents; D003470:Culture Media; D004275:DNA, Ribosomal; D012338:RNA, Ribosomal, 23S; D017291:Clarithromycin