Mutations in the genes for the subunits GyrA and ParC of the target enzymes DNA gyrase and topoisomerase IV are important mechanisms of resistance in quinolone-resistant bacteria, including Neisseria gonorrhoeae. The target enzymes also consist of the subunits GyrB and ParE, respectively, though their role in quinolone-resistance has not been fully investigated. We sequenced the quinolone-resistance-determining regions (QRDR) of gyrA, gyrB, parC, and parE in 25 ciprofloxacin-resistant strains from Bangladesh (MIC 4-->32 mg/l) and 5 susceptible strains of N. gonorrhoeae. All the resistant strains had three or four mutations. Two of these were at positions 91 and 95 of gyrA. Fourteen strains had an additional mutation in parC at position 91, and 17 strains had an additional mutation in parE in position 439. No alterations were found in gyrB. The five susceptible strains had identical DNA sequences. Data indicate that the mutations detected in the QRDR of gyrA and parC may be important in the development of quinolone resistance. According to transformation experiments we assume that the alteration in parE is not related to a high degree of quinolone resistance. There was no correlation between ciprofloxacin MICs and pattern or number of mutations in the target genes.

A highly discriminative and objective genetic characterization of N. gonorrhoeae, which increases our knowledge of strain populations in different geographic areas, is crucial for the development of improved control measures. In the present study, conventional phenotypic characterization and genetic characterization by means of pulsed-field gel electrophoresis (PFGE), sequencing of the entire porB gene, N. gonorrhoeae multiantigen sequence typing (NG-MAST), and pyrosequencing of a quinolone resistance determining region (QRDR) of the gyrA gene of Swedish ciprofloxacinresistant N. gonorrhoeae serovar IB-10 isolates (n=45) were performed. The genetic characterization identified one widely spread ciprofloxacin-resistant N. gonorrhoeae ST147 strain. In addition, isolates with slightly different genetic characteristics, which presumably reflect the ongoing evolution only, were also identified. All the isolates contained single nucleotide polymorphisms in QRDR of the gyrA gene that are highly correlated with ciprofloxacin resistance. Consequently, comprehensive characterization identified the first confirmed large domestic transmission, mainly among young heterosexuals, of one ciprofloxacin-resistant N. gonorrhoeae strain in Swedish society during [2002][2003]. In conclusion, a precise, i.e. genetic, characterization for identification of individual strains is a very valuable support to the crucial active surveillance of the epidemiological characteristics and the antibiotic susceptibility of N. gonorrhoeae in the effective treatment of gonorrhoea. KeywordsNeisseria gonorrhoeae; ciprofloxacin resistance; molecular epidemiology; porB gene; NG-MAST Gonorrhoea remains a major sexually transmitted infection (STI) in many countries (1,2). The mainstay in its prevention is based on the availability of effective diagnostics and antibiotic treatment, as well as regional, national, and international surveillance of the epidemiological characteristics and the antibiotic susceptibility of the etiological agent, i.e. Neisseria gonorrhoeae. Nowadays, a high level of decreased susceptibility or resistance to most traditional antibiotics used for treatment of gonorrhoea has been identified in most countries [2][3][4][5]). In addition, the characteristics of circulating N. gonorrhoeae strains fluctuate over time and a highly discriminative and objective characterization, i.e. genetic typing, of the bacteria, is crucial. This genetic typing may identify the transmission of more virulent and/or antibiotic-resistant strains, information that is important for the development of improved control measures. Conventional phenotypic characterization of N. gonorrhoeae strains has several limitations (6-10) and many genetic methods have been developed to overcome these shortcomings (11).Since 1997 the incidence of gonorrhoea in Sweden has increased almost annually (Gonorrhoea/ year and month statistics per county http://gis.smittskyddsinstitutet.se/mapapp/build/intro_eng.html (3,8)). According to previous studies (8,10,12), the transmi...

Four chromogenic urine culture media were compared to culture on blood agar, MacConkey agar, and CLED (cysteine-, lactose-, and electrolyte-deficient) agar for detection of uropathogens in 1,200 urine specimens. After 2 nights of incubation, 96% of all isolates were recovered on blood agar, 96% were recovered on CLED agar, 92% were recovered on CPS ID2, 96% were recovered on CHROMagar Orientation from BBL, 95% were recovered on CHROMagar Orientation from The CHROMagar Company, and 95% were recovered on Chromogenic UTI Medium.Chromogenic media have been compared to traditional urine culture media, e.g., blood agar and MacConkey agar, and been found to be at least as good as traditional media for the isolation of uropathogens (7,9,12,13). In one study, no significant differences between the isolation rates of different chromogenic media were found (2).Three articles reported the effect of incubation time on results of urine culture on traditional media (3,8,11). All agree that common uropathogens can be detected after overnight incubation and that a longer incubation time is required for the detection of yeasts.In this study, we evaluated four different chromogenic agars Blood agar, CLED (cysteine-, lactose-, and electrolyte-deficient) agar, and MacConkey agar were used as the reference media. We also compared overnight incubation to 2 nights of incubation; to our knowledge, this has not been done previously.The media evaluated are listed in Table 1. Blood agar, CLED agar, MacConkey agar, CHROMagar Orientation from The CHROMagar Company, and Chromogenic UTI Medium were prepared at the respective laboratories in accordance with the manufacturers' recommendations.CPS ID2 and CHROMagar Orientation from BBL were received as ready-made agar plates. Media prepared at the laboratories were tested for contamination by incubation of one plate from each batch at room temperature and one plate in ambient atmosphere at 36°C for 2 days.Each batch was also tested for typical colony appearance and growth with Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 13883, and Proteus mirabilis ATCC 29245.The media were compared by using quantitative culture with test strains. In this comparison, 10-l volumes of serial dilutions (starting from approximately 10 8 CFU/ml) of each test strain (E. coli ATCC 25922, E. faecalis ATCC 29212, and S. saprophyticus ATCC 15305) were inoculated onto each medium with a calibrated pipette (Finnpipette; Labsystems). Colonies were counted after 1 and 2 days of incubation in ambient atmosphere at 36°C.The media were also evaluated by using urine specimens sent in for routine culture. The first 50 urine specimens that arrived every day at each laboratory were included in the study. A total of 1,200 urine specimens were inoculated on all of the media tested. The laboratories serve both tertiary care hospitals and primary care centers. Most of the specimens included in the study were from inpatients, as the specimens collected at the ...