PPNG Strains Research Articles

Whole-genome sequence analysis of high-level penicillin-resistant strains and antimicrobial susceptibility of Neisseria gonorrhoeae clinical isolates from Thailand.

The increasing rate of antimicrobial-resistant Neisseria gonorrhoeae poses a considerable public health threat due to the difficulty in treating gonococcal infections. This study examined antimicrobial resistance (AMR) to drugs recommended for gonorrhea treatment between 2015 and 2017, and the AMR determinants and genetic compositions of plasmids in 3 gonococcal strains with high-level penicillin resistance. We collected 117 N. gonorrhoeae isolates from patients with gonococcal infections who attended Siriraj Hospital, Bangkok, Thailand, between 2015 and 2017. Minimum inhibitory concentrations (MICs) of penicillin, tetracycline, ciprofloxacin, azithromycin, spectinomycin, cefixime, and ceftriaxone were determined by the agar dilution method. PCR amplification and sequencing of 23S rRNA and mtrR (a negative regulator of MtrCDE efflux pump) were performed. Whole genomes of 3 PPNG strains with high-level penicillin resistance (MIC ≥ 128 μg/ml) were sequenced using Illumina and Nanopore sequencing platforms. The proportions of N. gonorrhoeae isolates with resistance were 84.6% for penicillin, 91.5% for tetracycline, and 96.6% for ciprofloxacin. All isolates were susceptible to spectinomycin, azithromycin, cefixime, and ceftriaxone. An adenine deletion within a 13 bp inverted repeat sequence in the mtrR promoter and an H105Y mutation in the mtrR coding region were found in the N. gonorrhoeae isolate with the highest azithromycin MIC value (1 μg/ml). Three high-level penicillin-resistant isolates contained nonmosaic type II penA and had mutations in penB and the mtrR coding region. All isolates with high-level penicillin resistance carried the conjugative plasmids with or without the Dutch type tetM determinant, the beta-lactamase plasmid (Rio/Toronto), and the cryptic plasmid. The gonococcal population in Thailand showed high susceptibility to ceftriaxone and azithromycin, current dual therapy recommended for gonorrhea treatment. As elevated MIC of azithromycin has been observed in 1 strain of N. gonorrhoeae, expanded and enhanced surveillance of antimicrobial susceptibility and study of genetic resistance determinants are essential to improve treatment guidelines.

Gonorrhoea surveillance system in France: 1986-2000.

The objectives of this study were to monitor epidemiologic trends in Neisseria gonorrhoeae (NG) infections and to assess antimicrobial resistance patterns of NG. RENAGO, a voluntary-based laboratory surveillance system, including private and public laboratories, was set up in France in 1986. Every NG strain isolated by the participating laboratories was sent to the National Reference Center, Institut Alfred Fournier, Paris, where susceptibility to 6 antibiotics was tested. These laboratories reported monthly numbers of positive NG isolates and associated epidemiologic data. Because the number of laboratories varied every year, the average number of NG isolates per laboratory per year was computed to monitor annual trends in gonorrhea incidence. The average number of NG isolated per laboratory per year decreased steadily from 10.6 in 1986 to 0.6 in 1997 but then yearly increased and reached 1.9 in 2000. Increasing gonorrhea was observed mostly in men and in the Paris area. The proportion of rectal strains increased significantly from 0.9% in 1986 to 9.2% in 2000. From 1998 to 2000, 5.3% of the isolates had reduced susceptibility or were resistant to ciprofloxacin, 7.3% were PPNG strains and 27.4% were resistant to tetracycline, 18.5% had a reduced susceptibility to thiamphenicol, and 1 strain was resistant to the latter. Neither strain was resistant to ceftriaxone or to spectinomycin. From 1998 to 2000, gonorrhea markedly increased in France and seemed to affect mainly gay men in Paris, which suggests relapses to risky sexual behaviors and highlights the need for strengthening prevention. During the same period, NG ciprofloxacin resistance has sharply increased and should be carefully monitored because of the wide use of ciprofloxacin single-dose treatment.

Plasmid-mediated resistance of Neisseria gonorrhoeae strains isolated from female sex workers in North Sumatra, Indonesia, 1996.

Sentinel surveillance of the antimicrobial resistance of strains isolated from female sex workers in North Sumatra, Indonesia, has been carried out since 1975. In 1996 a high prevalence of strains with plasmid-mediated resistance to tetracycline and penicillin was observed. The goal was to further characterize strains isolated from a core group of patients in Indonesia with sexually transmitted infections in 1996. The strains were characterized by antimicrobial susceptibility testing, plasmid analysis, subtype of the determinant, and analysis of genomic DNA by pulsed-field gel electrophoresis (PFGE). A total 161 strains obtained from 592 female sex workers in 10 different places in North Sumatra, Indonesia, in 1996 were investigated. All strains exhibited plasmid-mediated resistance to penicillin (PPNG: penicillinase-producing ) and/or tetracycline (TRNG: tetracycline-resistant ); 115 strains were PPNG/TRNG (71%), 45 were TRNG (28%), and 1 was PPNG. All strains were susceptible to ceftriaxone, ciprofloxacin, kanamycin, and spectinomycin. All PPNG strains tested carried the 7.2-kb (Asian type) plasmid except one, which carried the 4.9-kb (Toronto type) plasmid. All TRNG strains except one contained the Dutch-type gene. PFGE analysis of 156 strains documented that a diversity of strains existed and that certain genotypes had spread in a defined area or between different areas in North Sumatra. Our results underline the importance of continuous surveillance of the changing patterns of antimicrobial resistance of in high-risk populations.

Laparoscopic and microbiological features of acute salpingitis in developing countries

Summary One hundred and twenty-four out of 198 consecutive women who underwent diagnostic lasparoscopy for clinical symptoms and signs of acute salpingitis at the University College Hospital, Ibadan, Nigeria had acute salpingitis. These were slightly younger than those without acute salpingitis, otherwise there were no differences in the sociodemographic characteristics of the two groups. Urinary and gastrointestinal symptoms, abnormal vaginal discharge, fever ( 38 C) and sexually transmitted organisms were significantly more in women with acute salpingitis. Ninetyfive per cent of the Neisseria gonorrhoea cultured were of the PPNG strain. Pelvic adhesions were present in 69.4% of the women with acute salpingitis. Forty-one per cent of the women had tubal occlusion. It was concluded that laparoscopy rather than clinical findings alone would determine the severity of acute salpingitis. This should be performed along with culture of genital discharges and peritoneal fluid for optimum management. The use of a single dose broad spectrum antibiotics active against both PPNG and non-PPNG strains, and chlamydial infections is advocated for treatment in developing countries.

Increasing prevalence of penicillinase‐producing Neisseria gonorrhoeae and the emergence of high‐level, plasmid‐mediated tetracycline resistance among gonococcal isolates in The Gambia

One hundred and three strains of Neisseria gonorrhoeae isolated from a periurban STD clinic in The Gambia were studied for antimicrobial susceptibility, plasmid profile, and serogroup using standard procedures. Seventy-nine (77%) were penicillinase producers (PPNG) and fully resistant to penicillin (MIC > or = 8 mg/l). One isolate showed chromosomally induced resistance to penicillin (MIC 2 mg/l). None of the isolates was sensitive to tetracycline; 16 (16%) showed intermediate resistance (MICs 1-8 mg/l) and 87 (84%) showed high-level plasmid-mediated resistance (TRNG) (MICs > 10 mg/l). This is the first report of TRNG in The Gambia. Only 6 (6%) strains were fully sensitive to trimethoprim-sulphamethoxazole (MIC < 8 mg/l); 78 (76%) showed intermediate level resistance (MICs 8-16 mg/l) and 19 (18%) were fully resistant (MIC > 32 mg/l). Indications of an increase in MIC to ciprofloxacin and ceftriaxone were found in 6 (6%) and 1 (1%) strains, respectively, although all remained fully sensitive (MICs 0.004-0.03 mg/l and 0.001-0.015 mg/l). All PPNG and TRNG strains carried the 3.2 MDa and 25.2 MDa plasmids, respectively. All isolates carried the 2.6 MDa cryptic plasmid and 9 (3 PPNG and 6 non-PPNG) carried the 24.5 MDa conjugative plasmid. Forty-four (43%) strains were typed group W1, 58 (56%) W11/111 and 1 had cross-reacting antigens. Because PPNG are frequently encountered and high-level TRNG is now prevalent, the newer cephalosporins and quinolones must now be considered as first-line drugs for the treatment of gonorrhoea in The Gambia.

The virgin population of Neisseria gonorrhoeae in Stockholm has decreased and antimicrobial resistance is increasing.

To investigate the evolution of chromosomal and plasmid mediated resistance for ampicillin and tetracycline of N gonorrhoeae strains in Stockholm during 1982-1993. A total of 404 gonococcal strains isolated in 1982, 1987, 1990, 1992, 1993 were analysed for minimal inhibitory concentrations (MIC) of ampicillin and tetracycline and for plasmid content. MIC values were determined by the agar dilution method and plasmid preparations were performed using alkaline lysis. To detect additional gonococcal strains with tet(M) plasmids all strains isolated in 1988-1989 and 1991, in all 234 isolates, were analysed retrospectively for MIC values of tetracycline. If an MIC value of > or = 4.0 mg/l was recorded plasmid analysis was performed. Increased proportions of chromosomally mediated resistance to tetracycline (p < 0.001) as well as plasmid mediated resistance to both ampicillin (p < 0.02) and tetracycline were found in the later part of the study. In 1991 the first gonococcus with tet(M) plasmid was isolated in Sweden. The proportion of strains with chromosomally mediated resistance for ampicillin did not change during the study period. The proportion of gonococcal strains with the 39 kb conjugative plasmid was increased in the later part of the study. The increased proportion of N gonorrhoeae strains with resistance to ampicillin and tetracycline is most likely due to importation of strains from areas with high prevalence of antibiotic resistant gonococci. The proportion of N gonorrhoeae strains with tet(M) plasmids is low in Sweden, but might increase in the same way as the proportion of PPNG strains has increased during 1982-1993.

Rapid decline in penicillinase-producing Neisseria gonorrhoeae in Hong Kong associated with emerging 4-fluoroquinolone resistance.

OBJECTIVE--To study the changes in penicillinase-producing (PPNG) and high-level tetracycline resistant (TRNG) Neisseria gonorrhoeae isolated in Hong Kong associated with emerging quinolone resistance (QRNG) over a two year period from November 1992 to October 1994. MATERIALS AND METHODS--Four thousand and eighty-six strains of Neisseria gonorrhoeae isolated, of which 432 were PPNG, were examined for susceptibilities to penicillin and tetracycline by an agar dilution method using the breakpoint minimum inhibitory concentrations (MICs) of 1 and 10 mg/1 respectively. Ofloxacin susceptibility was done using 0.1 and 1 mg/l. Penicillinase production was detected by performing the chromogenic cephalosporin nitrocefin test on all penicillin resistant (MIC > 1 mg/l) strains. RESULTS--Three thousand and eighty (75.4%) and 79 (1.9%) strains were found to be penicillin resistant and TRNG (MIC > 10 mg/l) respectively. Sixty-nine strains (1.7%) were resistant to both, of which 54 (1.3%) were PPNG. Three strains were multiply-resistant to penicillin, tetracycline and ofloxacin; however, none was PPNG. While the percentage of penicillin resistant strains remained stable (mean 75.5%, SD 7.0), TRNG decreased from 4.5% to 2.1%. The most dramatic change was the sharp decline of PPNG from 25.5% in January 1993 to 4.3% in October 1994, concurrent with a linear increase in strains with ofloxacin MIC > 0.1 mg/l. Significant clinical failure was seen in strains having ofloxacin MIC > 1 mg/l (QRNG), which increased drastically from 0.5% to 10.4% during the study period. Selection against PPNG and TRNG strains appeared to occur only when fully quinolone-susceptible strains first become less susceptible (MIC > 0.1 mg/l), but not when these less susceptible strains become fully resistant (MIC > 1 mg/l). CONCLUSION--PPNG is now no longer hyperendemic in Hong Kong. Emergence of QRNG is associated with rapid decline of both PPNG and TRNG. This is the first report of plasmid-curing effect of the 4-fluoroquinolones occurring on an ecological scale.

Temporal changes in the gonococcal serovar patterns in Stockholm during two years with special reference to PPNG strains.

To analyse temporal changes in gonococcal serovar patterns in Stockholm during a two year study period (1987-1989) to elucidate the dynamics of gonorrhoea epidemiology. The study population comprised 857 patients with culture proven gonorrhoea and with serotyped gonococcal isolates. The probable geographical origin of the infection was determined in 690 of the patients. A total of 108 Ph/GS-serovars were identified. Most (73%) of the serovars were recognised only during one or two quarters of the study period and comprised 16% of the isolates. Seven serovars were encountered during all eight quarters. Three of these serovars i.e. Arost/Aedgkih (IA-1, IA-2), Bropt/Bajk (IB-3, IB-6), Brpyust/Bacejk (IB-1, IB-2) were the most prevalent in the overall study, accounting for 60% of the isolates during the first quarter of the study and 36% of the isolates during the last quarter. Fifty-seven percent of the patients were infected in Stockholm (endemic infection). The proportion of endemic isolates among the three most common serovars declined throughout the study period (77% during the first quarter; 47% during the last quarter). A total of 32 Ph/GS-serovars were recognised among 80 PPNG strains. Only four of these 32 serovars were encountered during more than two quarters. Of 57 patients with PPNG strains and with geographical origin of the infection known, only seven (12%), all infected in Sweden, might have transmitted their infection further into the society. The decline in the total number of gonorrhoea cases seen in Stockholm during the study period, was due mainly to a decline of endemic isolates of the three most prevalent serovars. Results from contact tracing and serotyping indicated that PPNG infections acquired abroad seldom become established in the community. Serovar determination seems valuable mainly as a tool for surveillance whereby the introduction and circulation of gonococcal strains in the community can be pursued.

Surveillance of sexually transmitted diseases in France: recent trends and incidence.

To present recent trends in sexually transmitted diseases (STDs) in France and to estimate the gonorrhoea incidence in 1990. Trends were analysed from data of three surveillance systems: (1) STD clinics: number of diagnoses, (2) a sentinel voluntary General Practitioner (GP) network: mean number of acute male urethritis/week/GP, characteristics of the notified urethritis (age, presence of discharge, sexual orientation), (3) a sentinel voluntary laboratory network: mean number of gonorrhoea isolates/month/laboratory, characteristics of patients with positive isolates (sex, age, site of sampling) and of strains (PPNG and TRNG rates). To estimate the gonorrhoea incidence in France in 1990, results of a study held among a national sample of laboratories were used, combined with data from surveillance systems and specific studies. Decreasing trends in gonorrhoea in STD clinics and in the laboratory network as well as in acute male urethritis in the GP network have been observed since implementation of the networks in 1985. The rate of PPNG strains has regularly increased in the laboratory network to reach 14% in 1991. Data suggest that the incidence in some acute non recurrent STDs could have increased among homo/bisexual men since 1988. Chlamydia trachomatis is now the most frequent diagnosis in STD clinics. Estimation of male gonorrhoea incidence rate in France in 1990 of 74/100,000 inhabitants (15-59 years) is consistent with figures observed in England and Wales, where the age distribution is very similar. On the other hand, the estimated female gonorrhoea incidence rate of 14/100,000, which concerns only microbiologically ascertained cases, is one third in France than that observed in England and Wales. The consistency of the decreasing trends in gonorrhoea and acute male urethritis observed from the different networks reduces the possibility of a bias due to any change in notification or in prescription. Trends in Chlamydia trachomatis will be better appraised in the near future with the recent implementation of new systems. The French STD surveillance appears quite satisfactory for male infections and has been able to show a marked decrease in the incidence of some STDs in the last years. Surveillance of female STDs is to be improved, in terms of monitored diagnoses and selected health care facilities. Differences between the female gonorrhoea incidence rate observed in England and Wales and the one computed for France could be attributed to differences in contact tracing policies between the two countries or to differences in sexual lifestyles.

Single-Dose Therapy of Anogenital and Pharyngeal Gonorrhoea with Ciprofloxacin

A single dose of ciprofloxacin, 250 mg by mouth, was used in an open study to treat pharyngeal or rectal gonorrhoea or both in 64 patients (32 men and 32 women). The study also included 151 men with urethral gonorrhoea and 53 women with cervical or urethral gonorrhoea. Ciprofloxacin cured 63 (98%) patients with pharyngeal or rectal gonorrhoea (including 5 patients with penicillinase-producing Neisseria gonorrhoeae; PPNG), 147 (97%) men with urethral gonorrhoea (including 8 with PPNG) and 52 (98%) women with cervical or urethral gonorrhoea. All the isolates of N. gonorrhoeae were sensitive to 0.03 mg/l of ciprofloxacin. Five of the 6 patients with treatment failure were subsequently cured by a single oral dose of ciprofloxacin 250 mg. None of the patients reported an adverse reaction. Ciprofloxacin 250 mg as a single oral dose is effective and safe in treating patients with pharyngeal or rectal gonorrhoea, including those with PPNG strains.

Characterisation of PPNG and non-PPNG Neisseria gonorrhoeae isolates from Singapore.

To characterise Neisseria gonorrhoeae isolates from Singapore. Characterisation of Neisseria gonorrhoeae isolates by auxotyping, serological analysis and plasmid profile analysis. Sixty randomly collected isolates from 41 symptomatic, untreated males and 19 female prostitutes were studied. Auxotyping of 25 PPNG and 35 non-PPNG strains showed that the Pro-auxotype was prevalent among both PPNG (56%) and non-PPNG (42.5%) strains. Prototrophic strains comprised 28% of PPNG and 32.5% of non-PPNG strains respectively. Serovar analysis showed that with the exception of seven serogroup WI strains, the majority belonged to serogroup WII/III. Serovar Aedih was predominant among both serogroup WI PPNG (80%) and non-PPNG (100%) strains. Serogroup WII/III PPNG strains were represented by nine serovars with the predominant serovars being Bacjk (28%) and Bcgjk (16%). Eleven serovars were identified in the WII/III non-PPNG strains and the major serovars were Bajk (20%), Bacjk (17%), Back (11.4%) and Beghjk (11.4%). Analysis of the 25 PPNG strains showed that 16 of them carried the 4.4 MDa (Asian type) resistance plasmid and nine strains harboured the 4.4 MDa plasmid in conjunction with the 24.5 MDa transfer plasmid. The cryptic plasmid of 2.6 MDa was present in 27 of the 35 non-PPNG strains. Five of the non-PPNG strains harbouring the cryptic plasmid also contained the 24.5 MDa transfer plasmid. The plasmid combination of 2.6 + 7.8 + 24.5 MDa was detected in three non-PPNG strains. The combination of epidemiological methods used in this study indicated the heterogeneity of N gonorrhoeae strains in Singapore. A total of 16 different combinations of auxotype, plasmid profile and serovar were seen in the 25 PPNG strains compared with 24 such combinations in the 35 non-PPNG strains. Such sensitive differentiation would otherwise not be possible using either auxotype-serovar (A/S) or auxotype-plasmid analysis.

Comparison of Single-Dose Ceftizoxime or Ceftriaxone in the Treatment of Uncomplicated Urethral Gonorrhea

Penicillinase-producing strains of Neisseria gonorrhoeae account for an increasing percentage of cases of gonorrhea in the United States. Although many strains of N. gonorrhoeae are still sensitive to penicillin, the CDC currently recommends one dose of ceftriaxone 250 mg IM for treatment of uncomplicated urethral gonorrhea. Ceftizoxime like ceftriaxone is a third generation cephalosporin that demonstrates excellent MICs against beta-lactamase positive and negative strains of N. gonorrhoeae. The clinical efficacy of a single-dose of ceftizoxime 250 mg IM was compared with ceftriaxone 250 mg IM in patients with uncomplicated urethral gonorrhea. In addition, the cost of each regimen was evaluated to determine the most cost-effective agent. A total of 106 and 98 patients were treated with ceftizoxime and ceftriaxone, respectively, with all cases cured. PPNG strains were observed in 25.5% of patients. No adverse events were observed or reported. The cost of ceftizoxime was approximately one-third that of ceftriaxone ($2.37 to $2.56 and $7.15 to $8.70 per dose, respectively). The data from this study suggest that ceftizoxime 250 mg IM is a safe, cost-effective alternative to the use of ceftriaxone 250 mg IM in the treatment of patients with PPNG-positive and -negative gonorrhea.

The epidemiology of Neisseria gonorrhoeae isolates in Dakar, Senegal 1982-1986: antimicrobial resistance, auxotypes and plasmid profiles.

A total of 460 Neisseria gonorrhoeae isolates from patients seen at three clinics in Dakar, Sénégal, 1982-1986, have been investigated. In this period a significant change in antimicrobial susceptibility was observed: the percentage of strains susceptible to penicillin (MIC less than or equal to 0.08 micrograms/ml) fell from 61 to 18 (p less than 0.0001) and the percentage of resistant strains (MIC greater than or equal to 1.2 micrograms/ml) increased from 18 to 46. Among penicillin-resistant strains the proportion of penicillinase-producing strains (PPNG) was fairly constant (range 35-55%). The determination of susceptibility to anti-microbial agents performed locally allowed detection of approximately all PPNG strains whereas the increase in the occurrence of strains with chromosomally determined resistance was not revealed. The study comprised 70 PPNG strains of which 19% (13/70) carried the 7.4 kb Asian plasmid and 81% (57/70) the 5.3 kb African plasmid. None of these strains possessed the 38 kb conjugative plasmid, whereas it was found in 4.5% of the 376 non-PPNG strains available for plasmid analysis; 92% (410/446) of all strains had the small 4.2 kb plasmid and 5.4% (24/446) did not contain any plasmid. Overall, auxotype zero and proline-requiring strains were predominant, accounting for 53% (244/460) and 28% (131/460), respectively. In general, PPNG strains carrying the 5.3 kb plasmid were auxotype zero (49/57 = 86%) and those carrying the 7.4 kb plasmid were proline-requiring (9/13 = 69%).

Trends in Resistance of Neisseria gonorrhoeae to Antimicrobial Agents in the United States

Resistance of Neisseria gonorrhoeae to antimicrobial agents is increasing in the United States. The number of cases of gonorrhea caused by beta-lactamase-producing strains of N. gonorrhoeae (PPNG) increased for the second consecutive year, and 16,608 were reported in 1986; these accounted for greater than 1.6% of all cases of gonorrhea. PPNG is endemic in Florida, New York City, and Los Angeles, and these areas may serve as foci for spread of PPNG strains in the United States. In 1985 N. gonorrhoeae strains that exhibited high-level resistance to tetracycline (TRNG; MIC, greater than or equal to 16.0 micrograms/ml) were reported. Tetracycline resistance was due to the tetM determinant in a 25.2-MDa tetM-conjugative plasmid. The prevalence of TRNG infections was greater than 4% in at least two communities. Strains with chromosomally-mediated resistance to several antimicrobial agents have been isolated more often; 399 cases were reported during the first half of 1986. Spectinomycin-resistant strains have been isolated in several cities, and strains with decreased susceptibility to ceftriaxone have been isolated. Phenotypic characterizations of strains of N. gonorrhoeae by auxotype and serovar, plasmid content, and antibiograms have permitted more detailed study of the heterogeneity and dynamics of strain populations. Characterization of outbreaks caused by resistant strains and surveillance of regional and temporal changes in antimicrobial resistance in gonococcal strain populations may be used in design of innovative strategies for gonorrhea control and for making anticipatory changes in recommended therapies for gonorrhea.

Evaluation of a fluorescent monoclonal antibody reagent for identification of cultured Neisseria gonorrhoeae.

We evaluated a new fluorescent monoclonal antibody reagent for confirmation of identity of Neisseria gonorrhoeae. The reagent correctly identified all 161 fresh clinical isolates of N. gonorrhoeae, which included 11 penicillinase producing strains (PPNG). The reagent also correctly identified 21 stored PPNG strains. No cross reactions were seen with 58 fresh clinical isolates of N. meningitidis, 12 stored strains of N. lactamica, or with strains of Gardnerella vaginalis, lactobacilli, Candida spp., Staphylococcus epidermidis or Enterobacteriaceae. Some cross reaction was noted with strains of S. aureus, probably related to cell-wall protein. A. However, this reagent was highly sensitive and specific for use against oxidase positive, gram-negative cocci isolated in London.

Antibiotic resistance, plasmid content and auxotypes of Neisseria gonorrhoeae in Greece.

The antibiotic resistance pattern, the plasmid content and the auxotypes of 27 PPNG and 200 non-PPNG isolates obtained in 1984-1985 were examined. The well-known plasmid patterns, the most frequent was the combination of 4.5 and well-known plasmid patterns, the most frequent was the combination of 4.5 and 2.6 Mdal plasmids. The strains with the Asian-type (4.5 Mdal) plasmid belonged to the auxotypes Pro and Zero, whereas those with the African type (3.2 Mdal) plasmid were of auxotypes Zero, Arg and Pro, Arg. All PPNG strains exhibited reduced sensitivity at least to one of the other antibiotics tested (cefotaxime, spectinomycin, thiamphenicol, tetracycline). Among non-PPNG strains, 19% harboured the conjugative and the cryptic plasmid, 67.5% only the cryptic, 1% only the conjugative and 12% were plasmid-free. The most frequent auxotypes of non-PPNG strains were Zero (65.5%) and Pro (21%), while the uncommon auxotype Pro, Arg degree, Ura was found only in plasmid-free strains with reduced sensitivity to penicillin. Susceptibility testing revealed a large number of non-PPNG strains with decreased sensitivity to antibiotics, the Pro and Zero isolates being less sensitive than those of other auxotypes.

Auxotypes, plasmid contents, and serovars of gonococcal strains (PPNG and non-PPNG) from Jamaica.

The analysis of the auxotypes and plasmid profiles of 459 non-PPNG strains from Jamaica suggests that strains have been imported to the island. Unlike in many developing countries where strains are differentiated by only a few auxotypes, 13 different auxotypes were identified in the non-PPNG strains. In Jamaica over 10% of the strains were plasmid free and required proline, citrulline, and uracil (PCU-) for growth. These isolates predominate in Canada and are increasingly reported from areas of the United States of America and Europe. The serological analysis of 168 of the non-PPNG strains indicated that most (76%, 128) were from serogroup WII/III. Serogroup WII/III strains comprised 17 serovar combinations with GS and Ph reagents, whereas serogroup WI strains included only four serovars. Unusually, most WI Aedgkih non-PPNG strains were wild type or proline requiring. Strains of serovar Aedg were especially noted (in 93%, 13/14) for carriage of the transfer plasmid. The first 20 PPNG strains isolated in Jamaica proved to have multiple origins as they had eight variations of auxotype, serovar, and plasmid content. Most (60%, 12/20) of those isolated were typed as serogroup WI, and 10 of these isolates were serovar Aedgkih. Although most (70%, 14/20) PPNG strains harboured African type plasmids with or without transfer plasmids, six also carried Asian type plasmids (with the transfer plasmid).

Chromosomal resistance of gonococci to antibiotics.

Three hundred and twenty nine strains of non-penicillinase-producing Neisseria gonorrhoeae (non-PPNG) isolated from men and women were tested for their susceptibility to a range of antibiotics, and were also auxotyped and serogrouped. Nearly 6% (18) of 312 strains tested were resistant to 1 mg/l or more penicillin (compared with 4.4% of PPNG strains isolated in 1981). Many (198, 64%) strains showed intermediate resistance to penicillin (0.12-0.5 mg/l). Nearly 5% (15) of 312 strains tested were resistant to 0.5 mg/l or more cefuroxime, and there was a high degree of cross resistance between these two antibiotics. High levels of resistance to erythromycin and tetracycline were also found, and there was also appreciable cross resistance between these antibiotics and the beta lactam drugs. Resistance to spectinomycin was rare, and there was no cross resistance between spectinomycin and other agents tested. Levels of resistance between strains isolated from different anatomical sites did not differ, except that resistance to erythromycin was greater in rectal isolates. Four main auxotypes were detected. Strains requiring arginine, hypoxanthine, and uracil (AHU-) were more prevalent from the cervix. We have shown that there is an association between auxotype, serogroup, and level of sensitivity to penicillin, cefuroxime, and tetracycline.

Antibiotic susceptibility in relation to serogroup and auxotype of Neisseria gonorrhoeae isolates from Gabon.

We tested 75 beta-lactamase-positive (penicillinase-producing Neisseria gonorrhoeae; PPNG) and 147 beta-lactamase negative (non-PPNG) strains of N. gonorrhoeae obtained during a two-year period in Franceville, a semirural community in southeastern Gabon, for susceptibility to antimicrobial agents, auxotype, and serotype. The most common auxotypes were the nonrequiring and proline-requiring strains. Of the non-PPNG strains tested, 37% belonged to serogroup WI, 48% to serogroup WII, and 15% could not be grouped with commercially available antisera. Except for four strains that belonged to serogroup WII, the PPNG strains were classified as serogroup WI or ungroupable. We determined the concentrations at which 90% of strains were inhibited (MIC90) for spectinomycin (32 mg/liter for both PPNG and non-PPNG), kanamycin (32 mg/liter for both PPNG and non-PPNG), tetracycline (2 mg/liter for non-PPNG, 1 mg/liter for PPNG), cefotaxime (0.03 mg/liter for non-PPNG, 0.008 mg/liter for PPNG), and penicillin (1 mg/liter for non-PPNG, greater than 32 mg/liter for PPNG). A MIC of greater than or equal to 2 mg of tetracycline/liter was noted for 17% of the strains. Strains belonging to serogroup WII were more resistant to tetracycline and cefotaxime than other strains. Proline-requiring strains were less susceptible to tetracycline, cefotaxime, and spectinomycin than the nonrequiring strains. The decreased sensitivity to penicillin (non-PPNG strains) and tetracycline was determined by proline-requiring strains belonging to serogroup WII.

Serovars, auxotypes, and plasmid contents of PPNG strains from outbreak in Amsterdam.

The first outbreak of penicillinase producing strains of Neisseria gonorrhoeae (PPNG) in Amsterdam in 1981-2 was caused mainly by African strains carrying the 24 megadalton transfer plasmid (Afr+) that were non-requiring (NR) and inhibited by phenylalanine (pheni), but African strains without the transfer plasmid (Afr-) that were NRpheni and Afr+ NR strains were also found. Serological classification, using two monoclonal antibody systems, showed that three main serovars (Ae/Av, Aedih/Arst, and Bacejk/Brpyust) could be distinguished in these PPNG strains, which indicated exchanges of plasmids in these serovars. The serovar Ae/Av predominated in the Afr+ and Bacejk/Brpyust in the Afr- strains.