title: Quinolone resistance-determining region mutations and por type of Neisseria gonorrhoeae isolates: resistance surveillance and typing by molecular methodologies.
abstract: Quinolone resistance is increasing rapidly in Neisseria gonorrhoeae and is a significant public health problem that requires ongoing surveillance. To examine the feasibility of molecular surveillance of quinolone resistance, and to further characterize an outbreak of resistant N. gonorrhoeae in Israel, the quinolone resistance-determining region (QRDR) sequences and the por types of 80 N. gonorrhoeae isolates were determined using molecular techniques. QRDRs of gyrA and parC were amplified by polymerase chain reaction and were sequenced directly. The por type was determined by checkerboard hybridizations performed using oligonucleotide probes to regions encoding 5 variable loops of the porin protein. All 42 ciprofloxacin-resistant (CipR) isolates had mutations in QRDRs of both gyrA and parC, and identical mutations were found in 93% of these isolates. One intermediately resistant isolate had 1 mutation in gyrA, and susceptible isolates showed no mutations. Forty isolates had 1 of 2 por types that differed only by an in-frame deletion in variable region 5; all but 1 of these isolates were CipR. QRDR sequencing and por type determination showed that the outbreak of CipR N. gonorrhoeae in Israel was clonal. QRDR mutations were consistent with those previously characterized; this indicates that DNA probes can be developed for rapid detection and surveillance of quinolone-resistant N. gonorrhoeae in settings in which nonculture diagnostic methods are used.
authors.affiliation: Division of Allergies and Infectious Disease, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA. jgiles4@jhmi.edu
authors.forename: Julie A
authors.initials: JA
authors.lastname: Giles
authors.forename: Jason
authors.initials: J
authors.lastname: Falconio
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Yuenger
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Zenilman
authors.forename: Michael
authors.initials: M
authors.lastname: Dan
authors.forename: Margaret C
authors.initials: MC
authors.lastname: Bash
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D001483:Base Sequence; D002939:Ciprofloxacin / Q000494:pharmacology*; D027081:DNA Gyrase / Q000737:chemistry / Q000235:genetics; D027101:DNA Topoisomerase IV / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005260:Female; D006069:Gonorrhea / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D009344:Neisseria gonorrhoeae / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D018272:Porins / Q000737:chemistry / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D018272:Porins; C057699:porin protein, Neisseria; D002939:Ciprofloxacin; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase