Tetracycline-resistant Neisseria Gonorrhoeae Research Articles

Investigating the cause of increased tetracycline-resistant Neisseria gonorrhoeae in England, 2016-20.

Antimicrobial resistance in Neisseria gonorrhoeae is a global public health concern. Tetracycline resistance (TetR) increased from 39.4% to 75.2% between 2016 and 2021 in N. gonorrhoeae isolates collected through national surveillance in England, despite the absence of use of tetracyclines for the treatment of gonorrhoea. We investigated whether there was correlation between bacterial sexually transmitted infection (STI) tests performed and treatment with antimicrobials, with increased TetR in N. gonorrhoeae. We examined correlations between bacterial STI tests, antimicrobial treatment and TetR in N. gonorrhoeae, using national surveillance data from three large sexual health services (SHS) in London during 2016-20. Doxycycline prescribing data and antibiograms of a non-STI pathogen from distinct patient groups (sexual health, obstetric and paediatric), at a large London hospital, were analysed to identify if doxycycline use in SHS was associated with resistance in a non-STI organism. A substantial increase in TetR was observed, particularly in isolates from gay, bisexual and other MSM (GBMSM). Strong positive correlations were observed exclusively in GBMSM between N. gonorrhoeae TetR and both bacterial STI tests (r = 0.97, P = 0.01) and antimicrobial treatment (r = 0.87, P = 0.05). Doxycycline prescribing increased dramatically during the study period in SHS. Prevalence of TetR in Staphylococcus aureus was higher in isolates sourced from SHS attendees than those from other settings. Frequent screening of GBMSM at higher risk of STIs, such as those on pre-exposure prophylaxis (PrEP) leading to/and increased use of doxycycline for the treatment of diagnosed infections, may account for the increase in TetR in N. gonorrhoeae.

Predominance of High-Level Tetracycline-Resistant Neisseria gonorrhoeae in Kenya: Implications for Global Implementation of Doxycycline Postexposure Prophylaxis for Prevention of Sexually Transmitted Infections.

Using archived Neisseria gonorrhoeae samples from 2008 to 2012, the prevalence of tet (M) genemediating high-level tetracycline resistance in N. gonorrhoeae was 96% among 50 Kenyan women. Determining the local and national prevalence of gonococcal tetracycline resistance and surveillance of gonococcal antimicrobial resistance can inform the implementation of doxycycline postexposure prophylaxis for STI prevention.

Investigation of Streptomyces sp. Strain EMB24 Secondary Metabolite Profile Has Unraveled Its Extraordinary Antibacterial Potency Against Drug-Resistant Bacteria.

With the overuse and misuse of antibiotics amid COVID-19 pandemic, the antimicrobial resistance, which is already a global challenge, has accelerated its pace significantly. Finding novel and potential antibiotics seems one of the probable solutions. In this work, a novel Streptomyces sp. strain EMB24 was isolated and found to be an excellent source of antimicrobials as confirmed by agar-plug assay. It showed antibacterial activity against infection-causing bacteria, namely Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. In addition, Streptomyces sp. strain EMB24 inhibited the growth methicillin-resistant Staphylococcus aureus (MRSA), tetracycline-resistant Neisseria gonorrhoeae, and ampicillin-resistant Neisseria gonorrhoeae. Furthermore, to get deep insights about the genome and biosynthetic gene clusters producing antibiotics, whole genome sequencing was done. The strain EMB24 is closely related to the Streptomyces longispororuber as revealed by phylogenetic analysis which is a potential source of antibiotics and pigments as undecylprodigiosin and metacycloprodigiosin belonging to the class prodigiosin. Naphthyridinomycin, alkylresorcinols, desferrioxamine B and E, venezuelin, aborycin, MS-271, and siamycin are potent therapeutics that shared 100% similarity with the reference strain as revealed by the online antiSMASH tool.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10126-022-10168-2.

Biologically synthesized silver nanoparticles by Streptomyces sp. EMB24 extracts used against the drug-resistant bacteria

Drug resistance to common antibiotics has resurfaced, prompting the development of novel therapeutics such as nanoparticles (NPs). In this work, the silver nanoparticles (AgNPs) were synthesized by the cell-free extract produced by the Streptomyces strain and characterized using standard analytical techniques. The size of NPs was found to be in the range of 10-30 nm. The biologically synthesized AgNPs exhibit potent antibacterial activity against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli. In addition, AgNPs inhibited the growth of clinically isolated pathogenic strains, including Methicillin-resistant Staphylococcus aureus (MRSA) and tetracycline-resistant Neisseria gonorrhoeae. Furthermore, these AgNPs have reduced the development of Pseudomonas aeruginosa biofilm by 80%, one of the key contributors to the increased resistance among bacteria. The inhibition was confirmed using crystal violet assay and confocal microscopic images indicating the future application of AgNPs as a coating material on medical devices used in treating patients to inhibit biofilm formation.

Tetracycline-resistant Neisseria gonorrhoeae strains isolated in a Grade III hospital in eastern China: molecular characteristics and genetic diversity

Objective To analyze the genotypes of Neisseria gonorrhoeae (N.gonorrhoeae) epidemic strains in Wenzhou, eastern China, and to study the mechanism of tetracycline resistance in these strains. Methods A total of 77 N. gonorrhoeae strains were isolated from patients with gonorrhea. Antimicrobial susceptibility of these strains to penicillin, tetracycline, ciprofloxacin, spectinomycin, ceftriaxone and azithromycin was analyzed using E-test. PCR and DNA sequencing were used to detect the genes associated with tetracycline resistance, such as Tet-M, mtrR promoter region and mtrR coding region. N. gonorrhoeae multi-antigen sequence typing (NG-MAST) and multilocus sequence typing (MLST) were used to determine the molecular characteristics of all clinical isolates and tetracycline-resistant isolates, respectively. Results Among the 77 N. gonorrhoeae isolates, 74 (96.10%), 27 (35.06%) , 70 (90.91%) and 15 (19.48%) were resistant to penicillin, tetracycline, ciprofloxacin and azithromycin, respectively. All tested isolates were susceptible to spectinomycin and ceftriaxone. Nineteen isolates were resistant to tetracycline and all of them carried Tet-M gene. Among them, 17 had one deletion mutation of base A in mtrR promoter region and three had G45D mutation in mtrR coding region. NG-MAST classified the 19 tetracycline-resistant isolates into 11 different sequence types (ST). ST14781, ST1766 and ST1866 each accounted for 15.79% (three strains). Two ST (10.52%, 2/19) found in the present study had not been reported previously in the NG-MAST database. MLST showed the 19 tetracycline-resistant isolates belonged to 12 different STs, in which ST10899 accounted for 26.32% (five strains) and ST1600 accounted for 15.79% (three strains). Conclusions Mutations in mtrR promoter region and carrying Tet-M gene were associated with tetracycline resistance in N. gonorrhoeae. Clinical strains isolated in Wenzhou showed considerable molecular diversity. Measures should be implemented to monitor the spread of NG-MAST ST1766 and MLST ST1600 N. gonorrhoeae clones with high resistance to tetracycline in Wenzhou. Key words: Neisseria gonorrhoeae; Resistance rate; Tetracycline; NG-MAST; MLST

Plasmid-mediated resistance to tetracyclines among Neisseria gonorrhoeae strains isolated in Poland between 2012 and 2013.

IntroductionOne of two main mechanisms of resistance in tetracycline-resistant Neisseria gonorrhoeae (TRNG) is associated with the presence of TetM protein responsible for actively blocking of the tetracycline target site in the 30S ribosomal subunit. This mechanism is encoded by conjugative plasmids. The second mechanism is chromosomal in nature and due to mutations in specific genes.AimTo determine the incidence and type of tetM determinants in TRNG strains isolated from patients presenting with gonorrhea infection to the Dermatology and Venereology Clinic in Warsaw in 2012–2013.Material and methodsTetracycline and doxycycline susceptibility was determined by E-Tests. The presence and type of the tetM gene were determined by polymerase chain reaction.ResultsTetracycline resistance was detected in 50.8% of the evaluated strains. The TRNG strains containing the tetM plasmid constituted 13.8% of all the evaluated strains. Dutch type tetM constituted 12.3% and American type tetM 1.5% of all the evaluated strains. In the remaining TRNG strains, resistance to tetracyclines was presumably chromosome-encoded. The minimal inhibitory concentration (MIC) of tetracycline ranged from 0.25 to 32.0 mg/l, MIC50 = 2.0 mg/l, MIC90 = 32.0 mg/l. The MIC of doxycycline ranged from 0.25 to 32.0 mg/l, MIC50 = 4.0 mg/l, MIC90 = 16.0 mg/l.ConclusionsUnlike most of European countries, in 2012–2013 in Poland, the Dutch type tetM was found to be much more common than the American type. Minimal inhibitory concentration values of tetracycline and doxycycline were similar, with doxycycline exhibiting a somewhat lower effectiveness in vitro than tetracycline towards chromosome-mediated tetracycline resistant strains of N. gonorrhoeae.

Increasing Incidence of High-Level Tetracycline-Resistant Neisseria gonorrhoeae due to Clonal Spread and Foreign Import.

PurposeThe detection of high-level tetracycline-resistant strains of Neisseria gonorrhoeae (TRNG) can make important epidemiological contributions that are relevant to controlling infections from this pathogen. In this study, we aimed to determine the incidence of TRNG isolates over time and also to investigate the characteristics and genetic epidemiology of these TRNG isolates in Korea.Materials and MethodsThe antimicrobial susceptibilities of 601 isolates of N. gonorrhoeae from 2004 to 2011 were tested by standard Clinical and Laboratory Standards Institute methods. To determine the molecular epidemiological relatedness, N. gonorrhoeae multi-antigen sequence typing was performed.ResultsThe incidence of TRNG increased from 2% in 2004 to 21% in 2011. The minimum inhibitory concentration distributions of ceftriaxone and susceptibility of ciprofloxacin in TRNG were different from non-TRNG and varied according to the year of isolation. Most of the TRNG isolates collected from 2004 to 2007 exhibited genetic relatedness, with sequence type (ST) 1798 being the most common. From 2008 to 2011, the STs of the isolates became more variable and introduction of genetically unrelated TRNG were noted.ConclusionThe increased incidence of TRNG strains until 2007 appears to be due, at least in part, to clonal spread. However, we propose that the emergence of various STs since 2008 could be associated with foreign import.

Infection with neisseria gonorrhoeae and association between rising ceftriaxone minumum inhibitory concentration and men who have sex with men

Objectives The aim of this study was to review patients presenting with Neisseria gonorrhoeae over a 5 year period. Methods We performed a retrospective cohort study, using a prospective database and retrospective review of medical records, of patients with gonorrhoea infection presenting between January 2008 and November 2013. Results 215 patients screened positive by NAAT and treatment failure occurred in 2 patients after both initially received treatment with ciprofloxacin. of the 106 culture positive Neisseria gonorrhoeae isolates, 37 had ceftriaxone MIC >0.008. In addition, there were 4 penicillinase producing Neisseria gonorrhoeae (PPNG) isolates, 30 quinolone resistant Neisseria gonorrhoeae (QRNG) isolates, 9 tetracycline resistant Neisseria gonorrhoeae (TRNG) isolates and 4 isolates resistant to azithromycin. On a multivariate model, an association was seen between ceftriaxone MIC >0.008 and a history of men who have sex with men (MSM, OR 11.81, 95% CI 2.51–55.59, p = 0.02). Univariate analysis was statistically significant for infection involving either rectal or pharyngeal sites (OR 3.02, 95 CI 1.24–7.34, p = 0.02). Conclusion Screening for Neisseria gonorrhoea in rectal and pharyngeal sites is important amongst patients presenting with a history of MSM. Rising ceftriaxone MIC is associated with MSM and infection in rectal or pharyngeal sites.

Surveillance of antimicrobial susceptibilities of Neisseria gonorrhoeae in Nanning, China, 2000 to 2012.

To monitor the frequency of antibiotic resistance of Neisseria gonorrhoeae (NG) in Nanning, China, between 2000 and 2012. The production of β-lactamase by NG isolates was determined using the paper acidometric testing method. Antimicrobial susceptibility testing was performed for tetracycline, ciprofloxacin, spectinomycin, and ceftriaxone using the agar dilution method. The χ(2) test, t test, and univariate and multivariate analyses were used to analyze the statistical difference of the results. A total of 923 NG isolates were collected in Nanning between 2000 and 2012. Among these, 131 (14.2%) were penicillinase-producing NG, 520 (56.3%) isolates were tetracycline-resistant NG, and 857 (92.9%) isolates were ciprofloxacin-resistant strains. One spectinomycin-resistant strain was identified in 2000. There were 304 (32.9%) isolates with decreased susceptibility to ceftriaxone; the proportion of such isolates increased from 22.8% in 2000 to 2002 to 48.9% in 2006 to 2008 (P < 0.001), followed by a fall to 32.2% in 2009 to 2012 (P = 0.001). Patients' age of 16 to 25 years and isolate collection period of 2008 to 2012 (except 2011) were demonstrated to be risk factors for infection with isolates with decreased susceptibility to ceftriaxone. Antimicrobial susceptibility of NG isolates obtained from patients in Nanning from 2000 to 2012 was characterized by high occurrence of penicillinase-producing NG, tetracycline-resistant NG, and ciprofloxacin-resistant strains. Spectinomycin and ceftriaxone can be considered drugs of choice for empirical treatment of NG infection in Nanning. Moreover, we recommend a combination of 500 mg or higher dose of intramuscular ceftriaxone and 1 g oral azithromycin be used for the treatment of NG infection in Nanning and possibly in China.

Trend analysis of antibiotic resistance in Neisseria gonorrhoeae in Xi'an region, 2002-2009

Objective To monitor the antibiotic resistance in Neisseria gonorrhoeae, determine the prevalence of penicillinase-producing Neisseria gonorrhoeae (PPNG) and plasmid-mediated tetracycline-resistant Neisseria gonorrhoeae (TRNG) in Xi'an region, and to analyse the trends in antibiotic resistance in Neisseria gonorrhoeae. Methods In total, 647 strains of Neisseria gonorrhoeae were isolated from patients with gonorrhea in sexually transmitted disease (STD) clinic settings from 2002 to 2009. Agar dilution method was used to detect TRNG and determine the minimal inhibitory concentration (MIC) of antibiotics, and paper acidometric method to detect PPNG. Results Of these 647 strains, 216 (33.4%) were TRNG, 290 (44.8%)were PPNG. The prevalence of TRNG strains remained between 28.3% and 49.2% in 2002-2009, except for 17.3% in 2005; the prevalence of PPNG strains increased from 37.1% in 2002 to 64% in 2005, but declined from 2006 to 2009 (32.3%). The prevalence of resistance to spectinomycin maintained at a low level (0 to 2.8%) over these years, while that to ciprofloxacin remained higher than 80% from 2002 to 2009, and accounted for 100% in 2005, with the exception of 51% in 2006. Ceftriaxone resistance was observed in none of these strains except 4 isolates in 2003, but the susceptibility to ceftriaxone decreased yearly. Conclusions Neisseria gonorrhoeae is highly sensitive to spectinomycin, which should serve as the first treatment choice for gonorrhea.Full dose is necessary for the application of ceftriaxone in the treatment of gonorrhea. Ciprofloxacin should not be used to treat gonorrhea.

Detection of a novel Tet M determinant in tetracycline-resistant Neisseria gonorrhoeae from Uruguay, 1996-1999.

Determination of the diversity within the tet(M) sequence from N gonorrhoeae is a useful epidemiologic tool for monitoring the movement or importation of strains within a geographic region. Only two distinct tet(M) genes in clinical gonococcal isolates have been described up to now: the Dutch and the American types. The study involved surveillance of the tet(M) gene types in high-level-tetracycline-resistant gonococcal isolates from Uruguay during the period 1996 to 1999. Among 181 gonococcal isolates, those showing MICs >/=16 microg/ml to tetracycline were analyzed for detection and characterization of the tet(M) gene by a polymerase chain reaction (PCR) and further HpaII restriction fragment polymorphism methods, respectively. The plasmid content and antibiogram were determined. Twenty-two of 181 isolates (12%) exhibited high levels of resistance to tetracycline (MICs >/=16 microg/ml) and harbored a putative 25.2-Mda plasmid that contained the tet(M) gene. A high percentage of isolates (95%; 21/22) presented the Dutch type tet(M) gene. One isolate from 1999 revealed a new restriction pattern. Such a pattern had been previously noted in 1991. This new restriction pattern has not been described previously as occurring in isolates of N gonorrhoeae. The tet(M) amplimer sequence showed 100% identity with a previously described tet(M)-carrying plasmid from N meningitidis. A new HpaII restriction pattern of the tet(M) gene is present in low frequency. The tet(M) sequence was different from the gonococcal tet(M) sequences already known and not typable with the use of a differential PCR assay. Accordingly, with the genetic diversity already present within the tet(M) sequence of N gonorrhoeae isolates, we should be aware of the sensitivity of the PCR assays in use for tetracycline-resistant N gonorrhoeae detection.

Prevalence and tetM subtype of tetracycline-resistant Neisseria gonorrhoeae in Ohio, 1994.

Prevalence and tetM subtype of tetracycline-resistant Neisseria gonorrhoeae in Ohio, 1994.

Subtyping of high-level plasmid-mediated tetracycline resistant Neisseria gonorrhoeae isolated in Scotland between 1992 and 1998.

Tetracycline resistant Neisseria gonorrhoeae (TRNG) contain a 25.2 MDa TetM plasmid encoding a 68 KDa cytoplasmic protein which confers high-level tetracycline resistance. The aim of this study was to subtype all TRNG isolated in Scotland between 1992 and 1998. Subtyping was performed by a polymerase chain reaction (PCR) assay which characterizes the TetM plasmid as either the Dutch variant (443 base pair product) or the American variant (777 base pair product). Of the 78 TRNG isolates, 35 were the American variant and 43 were the Dutch variant. TRNG were distributed amongst 30 serovar/auxotype classes, the most common being 1A6/NR (11.5%), 1A6/P (14.1%) and 1B4/NR (14.1%). The country where infection was acquired was known for 36 of the 46 TRNG strains isolated between 1996 and 1998. All infections acquired in Asia and South America were the Dutch variant whereas all infections acquired in Africa were the American variant. A penicillinase plasmid was present in 66% (23/35) of the American variant TRNG compared with 51% (22/43) of the Dutch variant: the 3.2 MDa penicillinase plasmid was found in 87% of the American variant TRNG whereas the 4.4 MDa penicillinase plasmid was found in 68% of the Dutch variant TRNG. We conclude that subtyping of TRNG by PCR is a useful tool in studying the epidemiology of gonococcal infection due to plasmid-mediated resistant isolates.

High-level tetracycline-resistant Neisseria gonorrhoeae in Ontario, Canada--investigation of a cluster of isolates, showing chromosomally mediated resistance to penicillin combined with plasmid-mediated resistance to tetracycline.

Between 1991 and 1994, plasmid-mediated, tetracycline-resistant Neisseria gonorrhoeae (TRNG) increased from 61.8% to 85.96% of all resistant isolates in Ontario, Canada. Ninety-nine isolates with tetracycline MICs >32 mg/L were characterized by auxotype/serovar (A/S) class, plasmid profile, hybridization with eight tetracycline-resistant probes, and pulsed-field gel electrophoresis (PFGE) of genomic DNA after digestion with NheI and SpeI restriction endonucleases. A cluster of 82 isolates with penicillin MICs of 2-4 mg/L and tetracycline MICs of 128 mg/L (chromosomally mediated resistance) belonged to A/S class NR/IB-1 and had identical or closely related PFGE profiles. Seventeen isolates, TRNG (10) and penicillinase-producing TRNG (7), with tetracycline MICs of 64-256 mg/L, belonged to eight A/S classes and displayed 12 different PFGE profiles. The 99 isolates hybridized only with the TetM probe. Phenotypic and molecular characterization indicated a diverse population throughout the Province of Ontario.

Antimicrobial susceptibilities of strains of Neisseria gonorrhoeae in Bangkok, Thailand: 1994-1995.

Failure of uncomplicated gonococcal infections acquired in the Far East to respond to doses of ciprofloxacin and ofloxacin recommended by the Centers for Disease Control and Prevention have been identified in Australia, the United Kingdom, and the United States. In the Republic of the Philippines, 54.3% of strains exhibited decreased susceptibility to fluoroquinolones; 12% of strains were resistant to ciprofloxacin. This study was undertaken to compare the antimicrobial susceptibilities of gonococcal isolates in Bangkok, Thailand, with those in the Republic of the Philippines. To determine the frequency and diversity of antimicrobial resistance, particularly to fluoroquinolones, in gonococcal strains in Bangkok, Thailand. Strains of Neisseria gonorrhoeae isolated from 101 patients with uncomplicated gonorrhea in Bangkok, Thailand, in July, 1994 (46 strains) and November, 1994 to July, 1995 (55 strains), were characterized by auxotype/serovar class, antimicrobial susceptibilities, and plasmid profile. Susceptibilities were determined to penicillin G, tetracycline, ceftriaxone, cefixime, cefoxitin, ciprofloxacin, ofloxacin, norfloxacin, erythromycin, kanamycin, and thiamphenicol. Of 101 strains, 89.1% (90/101) were resistant to penicillin or tetracycline. Plasmid-mediated resistance to penicillin or tetracycline was identified in 33.7% (34/101) of the isolates: penicillinase-producing Neisseria gonorrhoeae (17.8%; 18/101), tetracycline-resistant Neisseria gonorrhoeae (7.9%; 8/101), and penicillinase-producing/tetracycline-resistant Neisseria gonorrhoeae (7.9%; 8/101). Most penicillinase-producing strains (96.2%; 25/26) possessed the 4.4-megadalton (Md) beta-lactamase plasmid; one strain possessed the 3.2-Md beta-lactamase plasmid. Chromosomally mediated resistance to penicillin and tetracycline was exhibited by 51.5% (52/101) of strains, and 4.0% (4/101) were tetracycline resistant. All strains were susceptible to spectinomycin. Of 21.8% (22/101) strains exhibiting decreased susceptibility to ciprofloxacin (minimal inhibitory concentration [MIC] > or = 0.125 microgram/ml), one strain (ciprofloxacin MIC, 0.5 microgram/ml; ciprofloxacin inhibition zone diameter of 23 mm) had MICs of 2.0 and 8.0 micrograms/ml for ofloxacin and norfloxacin, respectively, indicating resistance to these agents. Decreased susceptibility to ciprofloxacin was identified in strains with chromosomally mediated resistance to penicillin or tetracycline and in penicillinase-producing strains. In Bangkok, Thailand, gonococcal isolates exhibit resistance to penicillin, tetracycline, kanamycin, and thiamphenicol. Decreased susceptibility to fluoroquinolones is emerging in a variety of strains of N. gonorrhoeae. Thus, all gonococcal infections should be treated with antimicrobial therapies known to be active against all gonococcal strains to reduce the spread of strains exhibiting decreased susceptibilities to fluoroquinolones.

Auxotypes and serogroups of tetracycline-resistant Neisseria gonorrhoeae isolated in Malaysia.

Between 1992 and 1994, 253 tetracycline-resistant Neisseria gonorrhoeae (TRNG) strains were isolated and characterized by auxotype and serogroup (A/S) classes to study TRNG prevalence in different years. TRNG accounted for 28.1, 42.5, and 51.9% of the strains isolated in 1992, 1993, and 1994, respectively, showing a significant increase in each successive year (chi square = 26.7, P < 0.001). There was no significant increase in penicillinase-producing TRNG, which accounted for 53.1, 53.8, and 63.2% of the TRNG isolates. The 253 TRNG isolates belonged to 53 A/S classes. Eighteen A/S classes not observed in 1992 were detected in 1993, and 11 A/S classes not observed in 1992 and 1993 were isolated in 1994, indicating dissemination of the tetracycline resistance gene among the N. gonorrhoeae strains in Malaysia. Its emergence and subsequent rapid spread are alarming. The plasmid is capable of self-transfer (S.A. Morse, S.R. Johnson, J.W. Biddle, and M.C. Roberts, J. Infect. Dis. 155:819-822, 1987), allowing further dissemination of tetracycline resistance.

Gonococcal susceptibility to antimicrobials in Baltimore, 1988-1994. What was the impact of ciprofloxacin as first-line therapy for gonorrhea?

Single-dose, oral quinolones have been a recommended treatment option for gonorrhea since 1989 and have since been used as first-line therapy for gonorrhea in Baltimore. The impact of this strategy on antimicobial susceptibility patterns in Neisseria gonorrhoeae was assessed utilizing data collected as part of the National Gonococcal Isolate Surveillance system. This system evaluates a systematically collected sample. Minimum inhibitory concentrations to penicillin, tetracycline, ceftriaxone, and ciprofloxacin were determined by agar dilution. Between January 1988 and September 1994, 1,846 gonococcal isolates were evaluated. The proportion of isolates with plasmid-mediated resistance (penicillinase-producing Neisseria gonorrhoeae or tetracycline-resistant Neisseria gonorrhoeae) increased from 22% in 1988 to 46% in 1992 and then dropped to 20% in 1994. In contrast, the prevalence of chromosomally mediated resistant isolates ranged between 3% and 10%. Between 1988 and 1994, the geometric mean penicillin and tetracycline minimum inhibitory concentrations decreased slightly (penicillin: from 0.509 microgram/ml to 0.369 microgram/ml; tetracycline: from 1.01 micrograms/ml to 0.767 microgram/ml). The mean ceftriaxone MIC increased from 0.005 microgram/ml in 1988 to 0.021 microgram/ml in 1992, and then abruptly decreased. Ciprofloxacin minimum inhibitory concentrations did not change substantially during the study period. Concurrent studies performed in this community suggest that quinolones were infrequently used for infections other than sexually transmitted ones during this time period. Single-dose quinolone therapy does not appear to foster development of resistant gonococcal isolates. However, resistance may develop as a result of complex ecological interactions with the community, underscoring the need for continued surveillance.

Tetracycline-resistant Neisseria gonorrhoeae. Characteristics of patients and isolates at a London Genitourinary Medicine Clinic.

To compare auxotypes, serovars, and antibiograms of tetracycline-resistant Neisseria gonorrhoeae (TRNG) and non-TRNG isolated from patients attending an East London Genitourinary Medicine (GUM) Clinic. To obtain plasmid profiles for penicillinase-producing gonococci (PPNG) as well as presumptive TRNG. To identify differences in patient characteristics for the TRNG and non-TRNG patient groups. Gonococcal isolates were collected from 400 patients attending the GUM clinic at the Royal London Hospital GUM Clinic over a 1-year period. Isolates (378) were tested for susceptibility to various antibiotics, auxotyped, and serotyped. Plasmid profiles were obtained for PPNG and isolates exhibiting high-level tetracycline resistance (TRNG). The presence of the tet M determinant was confirmed using the polymerase chain reaction (PCR). The PCR product was digested with the restriction endonuclease (RE) Hpa II and electrophoresed on a 2.5% agarose gel to determine an "RE pattern." Patient data were collected by retrospective case-note review. TRNG (n = 42) accounted for 11% of the 378 isolates tested, and the remaining 336 (89%) isolates were non-TRNG. Non-requiring auxotrophy and P1B-2 serovar expression occurred more frequently among TRNG. PPNG accounted for 31% of TRNG and 5% of non-TRNG. Chromosomal resistance to penicillin (CMRNG) was absent among TRNG but accounted for 11% of non-TRNG. One TRNG isolate showed decreased susceptibility to ciprofloxacin (MIC 0.25 mg/l). All isolates were sensitive to cefotaxime, cefixime, spectinomycin, and azithromycin. All TRNG possessed the 25.2 MDa plasmid and produced a PCR product of appropriate size after tet M gene sequence amplification. RE digests of the PCR product gave a single pattern. None of the TRNG in contrast to 18% of the non-TRNG were acquired homosexually. Ethnic distribution differed between the patients with TRNG and patients without non-TRNG (Afro-Caribbean 81% versus 58%; white 19% versus 36%). Most TRNG were acquired in the United Kingdom. TRNG differ from the non-TRNG in their auxotype and serovar distribution. PPNG are more common among the TRNG isolates, whereas CMRNG appear absent. TRNG are isolated more commonly from Afro-Caribbean patients and were not represented among homosexually acquired isolates.

Plasmid-mediated antimicrobial resistance in Neisseria gonorrhoeae in Kingston, Jamaica: 1990-1991.

Gonococcal infections caused by antimicrobial-resistant strains of Neisseria gonorrhoeae have spread into many geographic areas and have increased in prevalence since the mid 1970s. Surveillance of antimicrobial-resistant gonococcal strains of Jamaica from 1981 to 1983 indicated that fewer than 3% of strains of produced beta-lactamase (penicillinase-producing Neisseria gonorrhoeae); approximately 4% of strains were resistant to penicillin, and 12% were resistant to tetracycline. To measure the frequency and nature of antimicrobial resistance in Neisseria gonorrhoeae isolates in Kingston, Jamaica, from 1990 to 1991 and to assess the effectiveness of prescribed treatment regimens. Urethral isolates of Neisseria gonorrhoeae from 116 heterosexual men with uncomplicated gonorrhea, representing 7.1% (116/1633) men attending the STD Comprehensive Health Centre from October 1990 through March 1991 who had positive Gram-stained smears, were characterized by auxotype, serovar, presence of the TetM determinant, and plasmid content. Antimicrobial susceptibilities to penicillin, cefoxitin, ceftriaxone, ciprofloxacin, tetracycline, and spectinomycin were determined by an agar dilution method. A total of 80.2% (93/116) of the isolates exhibited plasmid-mediated resistance to penicillin, tetracycline, or both: penicillinase-producing Neisseria gonorrhoeae (13/116; 11.2%), tetracycline-resistant Neisseria gonorrhoeae (25/116; 21.6%), and penicillinase-producing/tetracycline-resistant Neisseria gonorrhoeae, (55/116;47.4%). Isolates with chromosomally mediated resistance to penicillin, tetracycline, or both, accounted for 5.2% (6/116) of the isolates. Penicillinase-producing Neisseria gonorrhoeae, tetracycline-resistant Neisseria gonorrhoeae, and penicillinase-producing/tetracycline-resistant Neisseria gonorrhoeae belonging to multiple auxotype/serovar classes were isolated repeatedly through the study period. Infections caused by Neisseria gonorrhoeae exhibiting plasmid-mediated resistance to penicillin, tetracycline, or both, have become prevalent and endemic in Kingston, Jamaica. Therefore, all gonococcal infections should be treated with antimicrobial therapies known to be active against penicillin-resistant and tetracycline-resistant organisms to reduce gonorrhea transmission.

The distribution of variants of the Tet M determinant in tetracycline-resistant Neisseria gonorrhoeae.

Journal Article The distribution of variants of the Tet M determinant in tetracyclineresistant Neisseria gonorrhoeae Get access Deborah M. Gascoyne-Binzi Deborah M. Gascoyne-Binzi Department of Microbiology, The University of LeedsLeeds LS2 9JT, UK Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Antimicrobial Chemotherapy, Volume 33, Issue 5, May 1994, Pages 1011–1016, https://doi.org/10.1093/jac/33.5.1011 Published: 01 May 1994 Article history Received: 02 August 1993 Accepted: 21 December 1993 Published: 01 May 1994