High prevalence of high-level ciprofloxacin resistance in Neisseria gonorrhoeae in Tel Aviv, Israel: correlation with response to therapy

Dynamics of the sensitivity of N. gonorrhoeae strains found in the territory of the Russian Federation in 2010-2013 to antimicrobial drugs used for the treatment of gonococcal infection

Goal of the study. To study the sensitivity of N. gonorrhoeae strains found in the territory of the Russian Federation in 2010- 2013 to antimicrobial drugs. Materials and methods. During the monitoring of antibiotic resistance of N. gonorrhoeae in 2010-2013, phenotypic properties of N. gonorrhoeae strains to antimicrobial drugs (penicillin, tetracycline, ciprofloxacin, spectinomycin, azithromycin and ceftriaxone) were examined by the agar serial dilution technique. As many as 1,305 viable N. gonorrhoeae strains from different regions of the russian Federation were examined. The results were evaluated according to the criteria such as CLSI (Clinical and Laboratory Standards Institution) and EUCAST (European Committee for Antimicrobial Susceptibility Testing). The results were processed by using the WHONET software, version 5.4. Results. According to the results of a study of N. gonorrhoeae antibiotic resistance, N. gonorrhoeae is highly resistant to penicillin (in 2010 - 72.4%, in 2011 - 50.6%, in 2012 - 51.2%, in 2013 - 49.3%), to tetracycline (in 2010 - 68.5%, in 2011 - 55%, in 2012 - 61.9%, in 2013 - 49.3%) and ciprofloxacin (in 2010 - 56.2%, in 2011 - 37.1%, in 2012 - 35%, in 2013 - 24.6%) for the entire observation period without any substantial trend towards its reduction. During studies of the resistance of the gonococcal infection pathogen to spectinomycin, the share of non-sensitive strains to the antibiotic reduced from 16.7% in 2010 to 0.7% in 2013. A slight reduction in the share of non-sensitive N. gonorrhoeae strains to azithromycin was also observed (in 2010 - 15.3%, in 2011 - 25.3%, in 2012 - 17.5%, in 2013 - 9.9%) yet these data substantially exceed the level recommended by the WHO for prescribing an antimicrobial therapy. A high level of N. gonorrhoeae sensitivity to ceftriaxone (100%) was revealed in 2010-2013. Conclusions. According to the analysis of resistance of N. gonorrhoeae strains to antimicrobial drugs found in the territory of the russian Federation in 2010-2013, there is a trend towards the reduction in the number of non-sensitive N. gonorrhoeae strains to penicillin, tetracycline, ciprofloxacin, spectinomycin and azithromycin, which can confirm the efficacy of the Neisseria gonorrhoeae antibiotic resistance monitoring measures taken by State research Center of Dermatovenereology and Cosmetology since 2002.

Gonorrhoea

INTRODUCTION

In 2012, the diagnosis rates for gonorrhoea among adults aged 20 to 24 years in the UK were 249 per 100,000 for men and 140 per 100,000 for women. Resistance to one or more antimicrobial agent is reported in more than one quarter of isolates. Co-infection with Chlamydia trachomatis is reported in 10% to 40% of people with gonorrhoea in the US and UK.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for uncomplicated infections in men and non-pregnant women, and in pregnant women? What are the effects of treatments for disseminated gonococcal infection? What are the effects of dual treatment for gonorrhoea and chlamydia infection? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2013 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 7 studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotic regimens (dual treatment, multiple dose, single dose).

Gonorrhoea

INTRODUCTION

In the UK, diagnosis rates for gonorrhoea in 2008 were 152/100,000 for men aged 20 to 24 years and 135/100,000 for women aged 16 to 19 years. Resistance to one or more antimicrobial agent is reported in more than one quarter of isolates. Co-infection with Chlamydia trachomatis is reported in 10% to 40% of people with gonorrhoea in the US and UK.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for uncomplicated infections in men and non-pregnant women; and in pregnant women? What are the effects of treatments for disseminated gonococcal infection? What are the effects of dual treatment for gonorrhoea and chlamydia infection? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 24 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotic regimens (dual treatment, multiple dose, single dose).

Molecular analysis of antimicrobial resistance mechanisms in Neisseria gonorrhoeae isolates from Ontario, Canada

Surveillance of gonococcal antimicrobial resistance and the molecular characterization of the mechanisms underlying these resistance phenotypes are essential in order to establish correct empirical therapies, as well as to describe the emergence of new mechanisms in local bacterial populations. To address these goals, 149 isolates were collected over a 1-month period (October-November 2008) at the Ontario Public Health Laboratory, Toronto, Canada, and susceptibility profiles (8 antibiotics) were examined. Mutations in previously identified targets or the presence of some enzymes related to resistance (r), nonsusceptibility (ns) (resistant plus intermediate categories), or reduced susceptibility (rs) to the antibiotics tested were also studied. A significant proportion of nonsusceptibility to penicillin (PEN) (89.2%), tetracycline (TET) (72.3%), ciprofloxacin (CIP) (29%), and macrolides (erythromycin [ERY] and azithromycin; 22.3%) was found in these strains. Multidrug resistance was observed in 18.8% of the collection. Although all the strains were susceptible to spectinomycin and extended-spectrum cephalosporins (ESC) (ceftriaxone and cefixime), 9.4% of them displayed reduced susceptibility to extended-spectrum cephalosporins. PBP 2 mosaic structures were found in all of these ESC(rs) isolates. Alterations in the mtrR promoter, MtrR repressor (TET(r), PEN(ns), ESC(rs), and ERY(ns)), porin PIB (TET(r) and PEN(ns)), and ribosomal protein S10 (TET(r)) and double mutations in gyrA and parC quinolone resistance-determining regions (QRDRs) (CIP(r)) were associated with and presumably responsible for the resistance phenotypes observed. This is the first description of ESC(rs) in Canada. The detection of this phenotype indicates a change in the epidemiology of this resistance and highlights the importance of continued surveillance to preserve the last antimicrobial options available.

Selection of drugs for treatment of gonococcal infection based on the results ofthe monitoring of N. gonorrhoeae antibiotic resistance

The article presents recommendations for selecting drugs for treatment of gonococcal infection based on the results of the monitoring of N. gonorrhoeae antibiotic resistance in 2009 and 2005-2009. It was shown that it is not recommended to use penicillin, tetracycline and ciprofloxacin in the territory of the Russian Federation because of the high level of N. gonorrhoeae resistance to these drugs. The drug of choice for gonorrhea treatment in the Russian Federation is Ceftriaxon because of the high level of N. gonorrhoeae sensitivity (100%). It is recommended to use spectinomycin for gonorrhea treatment only in the Ural and Far Eastern Districts; azithromycin - only in the Ural and Central Districts characterized by the high level of N. gonorrhoeae sensitivity to these antimicrobial drugs, and it is necessary to use spectinomycin and azithromycin in other federal districts of Russia only under control of determination of N. gonorrhoeae sensitivity.

Trends in antimicrobial susceptibility of Neisseria gonorrhoeae in Israel, 2002 to 2007, with special reference to fluoroquinolone resistance

MICs for penicillin, tetracycline, ceftriaxone, ciprofloxacin, spectinomycin, and azithromycin were determined by the Etest method for 406 gonococcal strains obtained in 2002-2007 from an STI clinic and a general microbiology laboratory in Central Israel. A total of 27.1% were resistant to ciprofloxacin, with increasing resistance over the years All isolates remain susceptible to ceftriaxone and spectinomycin.

Sexually transmitted infections among brothel-based sex workers in Tel-Aviv area, Israel: high prevalence of pharyngeal gonorrhoea

Sex workers play a major role in spreading sexually transmitted infections (STIs). We studied the prevalence rates and risk factors for STIs among 300 brothel-based sex workers in Tel-Aviv. Throat swabs were cultured for Neisseria gonorrhoeae, urine samples were tested by polymerase chain reaction (PCR) for Chlamydia trachomatis and N. gonorrhoeae, and sera were tested for syphilis, human immunodeficiency virus (HIV) and type 2 herpes simplex virus (HSV) antibodies. N. gonorrhoeae was cultured from throat samples of 9.0% of participants; PCR testing of urine was positive for C. trachomatis in 6.3% and for N. gonorrhoeae in 5.0%. Syphilis serology was positive (Venereal Disease Research Laboratory [VDRL] titres >1:8) in 1.3% of women, HSV-2-specific immunoglobulin G was detected in 60% and HIV serology was positive in a single case (0.3%). Having STI was significantly associated with age, number of years in Israel, number of clients a week and condom use for vaginal sex. In a multivariate analysis, having STI was significantly associated with number of clients per week and condom use for vaginal sex. The high prevalence of pharyngeal gonorrhoea reflects most probably the expanding demand of clients for oral sex and the insufficient condom use in this form of sex.

Distinguishing importation from diversification of quinolone-resistant Neisseria gonorrhoeae by molecular evolutionary analysis

Background

Distinguishing the recent introduction of quinolone resistant gonococci into a population from diversification of resistant strains already in the population is important for planning effective infection control strategies. We applied molecular evolutionary analyses to DNA sequences from 9 housekeeping genes and gyrA, parC and porB of 24 quinolone resistant N. gonorrhoeae (QRNG) and 24 quinolone sensitive isolates collected in Israel during 2000–2001.

Results

Phylogenetic and eBURST analyses and estimates of divergence time indicated QRNG were introduced on 3 separate occasions and underwent limited diversification by mutation, deletion and horizontal gene transfer. Reconstruction of N. gonorrhoeae demography showed a slowly declining effective strain population size from 1976 to 1993, rapid decline between 1994 and 1999, and an increase from 1999 to 2001. This is partially attributable to declining gonorrhea case rates from 1973 to 1994. Additional contributing factors are selective sweeps of antibiotic resistant gonococci and increased transmission from sex workers. The abrupt decline in the mid-1990s heralded an increased incidence of gonorrhea from 1997 to the present. The subsequent increase in effective strain population size since 1999 reflects the increased gonococcal census population and introduction of quinolone resistance strains.

Conclusion

Our study demonstrates the effective use of population genetic approaches to assess recent and historical population dynamics of N. gonorrhoeae.

Update on the management of gonorrhea in adults in the United States

Gonorrhea, the second most commonly reported notifiable disease, is an important cause of cervicitis, urethritis, and pelvic inflammatory disease. The selection of appropriate therapy for gonorrhea (i.e., safe, highly effective, single dose, and affordable) is complicated by the ability of Neisseria gonorrhoeae to develop resistance to antimicrobial therapies. This article reviews the key questions and data that informed the 2006 gonorrhea treatment recommendations of the Centers for Disease Control and Prevention. Key areas addressed include the criteria used to select effective treatment for gonorrhea, the level of antimicrobial resistance at which changing treatment regimens is recommended, the epidemiology of resistance, and the use of quinolones, cephalosporins, and other classes of antimicrobials for the treatment of uncomplicated gonorrhea.

Gonorrhoea

INTRODUCTION

In the UK, diagnoses rates for gonorrhoea in 2005 were 196/100,000 for 20-24 year old men, and 133/100,000 for 16-19 year old women. Co-infection with Chlamydia trachomatis is reported in 10-40% of people with gonorrhoea in the USA and UK.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for uncomplicated infections in men and non-pregnant women; and in pregnant women? What are the effects of treatments for disseminated gonococcal infection? What are the effects of dual treatment for gonorrhoea and chlamydia infection? We searched: Medline, Embase, The Cochrane Library and other important databases up to July 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 21 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotic regimens (dual treatment, multiple dose, single dose).

Real-time PCR assay for detection of quinolone-resistant Neisseria gonorrhoeae in urine samples

A need exists for the development of applicable surveillance tools to detect fluoroquinolone-resistant Neisseria gonorrhoeae (QRNG) in urine samples. We describe here a real-time PCR assay for detecting mutations in the Ser91 codon of the gyrA gene of N. gonorrhoeae in urine specimens. We tested 96 urine samples collected along with Gonorrhea Isolate Surveillance Project (GISP) urethral swab samples and compared the results with matched MICs of ciprofloxacin, as reported by the regional GISP laboratory. We then tested 100 urine specimens, known to be gonorrhea positive by nucleic acid amplification testing, provided by females to challenge the real-time PCR assay with urine specimens containing potentially less target DNA content than specimens from symptomatic males. With an MIC threshold of 0.125 mug of ciprofloxacin/ml, our assay correctly identified resistance in 41 of 44 (93.2%; 95% confidence interval [CI] = 81.3 to 98.6%) corresponding resistant culture specimens and correctly identified 51 of 51 (100%; 95% CI = 93.0 to 100%) susceptible specimens. One specimen did not amplify. The assay successfully amplified the gyrA amplicon and determined a susceptibility genotype in 72 of 100 (72%) urine specimens collected from female patients. We developed an assay for detecting QRNG in urine specimens that correlated well with MIC results of cultured specimens and had moderate sensitivity with urine specimens. This methodology might fulfill the need for a QRNG detection system for urine specimens, a useful characteristic in the age of nucleic acid amplification testing for gonococcal infection.

Pharyngeal Gonorrhea in Female Sex Workers: Response to a Single 2-g Dose of Azithromycin

OBJECTIVES

A sharp increase in the incidence of gonorrhea has been observed in Tel Aviv, Israel, since 1999. Almost one half of interviewed patients admitted contracting the infection from a sex worker. In two thirds of the cases, oral sex (fellatio) was the most probable route of acquiring the disease. In the current study, we assessed the prevalence of pharyngeal gonorrhea among sex workers in Tel Aviv and evaluated the efficacy of a single 2-g dose of azithromycin in eradicating the infection.

METHODS

Throat specimens were obtained for gonococcal culture from 301 female sex workers practicing in brothels. A questionnaire covering demographic and sexual behavior information was administered to all participants, and a single 2-g dose was administered orally under supervision. Women with positive cultures were reexamined a week later for eradication of Neisseria gonorrhoeae.

RESULTS

N gonorrhoeae was isolated from 27 women (9%). The median age of women with pharyngeal gonorrhea was 23 years (range, 18-32 years); 85% were born in former Soviet Union (mostly Russia, Ukraine, Moldavia). Regular condom use in vaginal sex was reported by 88% of the participants, whereas only 60% reported always using condoms in oral sex. All isolates were susceptible to azithromycin (MIC < or = 0.5 microg/ml). Gonococci were eradicated in 20/21 individuals (95%).

CONCLUSION

A high carriage rate of gonococci in the throat and a low rate of condom use in oral sex were documented among sex workers in Tel Aviv. A single 2 g dose of azithromycin was very effective in eradicating gonococci from the throat.

Fluoroquinolone-resistant Neisseria gonorrhoeae: the inevitable epidemic

The worldwide incidence of fluoroquinolone-resistant Neisseria gonorrhoeae has increased dramatically in the last few years. Single doses of fluoroquinolones can no longer be used to treat N gonorrhoeae infections acquired in the Far East, parts of the Middle East, the Pacific Islands, and parts of Western Europe and the United States. Although California and Hawaii account for most of the current United States cases, the increased incidence of FQR in some high-risk groups independent of geography heralds an imminent spread of drug-resistant strains throughout the rest of the population. The use of molecular tests has revolutionized the diagnostic field in STIs. The main limitation of their application in N gonorrhoeae testing has been the loss of culture specimens that allow antimicrobial sensitivity testing. New molecular methods have made it possible to detect antimicrobial resistance without the use of live organisms. These tests hold the promise of improving epidemiologic tracking of N gonorrhoeae drug resistance, leading to better patient management at the local level. The loss of fluoroquinolones limits available oral regimens to a single CDC-recommended antibiotic, cefixime. Oral, inexpensive, single-dose alternatives are needed to ensure continued therapeutic success.

Drug-resistant Neisseria gonorrhoeae in Michigan

The increasing prevalence of quinolone-resistant Neisseria gonorrhoeae (QRNG) in the United States is a cause for concern. Detecting resistance is complicated by the widespread use of molecular tests that do not provide isolates for susceptibility testing. The Michigan Department of Community Health developed a sentinel surveillance program to detect antimicrobial drug resistance in N. gonorrhoeae. Sentinel surveillance from 11 laboratories submitted 1,122 isolates for antimicrobial drug susceptibility testing and detected 2 clusters of QRNG from January 2003 to September 2004. These clusters were epidemiologically distinct: one involved young, heterosexual youth, and the other involved older men who have sex with men. This finding led to changes in local treatment recommendations that limited spread of resistant strains. Development of the sentinel program, collection of data, and epidemiologic analysis of the clusters are discussed.

Use of applied biosystems 7900HT sequence detection system and Taqman assay for detection of quinolone-resistant Neisseria gonorrhoeae

Mutations in quinolone resistance-determining regions (QRDRs) have been associated with quinolone-resistant Neisseria gonorrhoeae (QRNG). Since diagnostic nucleic acid amplification tests for gonococci are now in frequent use, molecular detection of QRNG could facilitate surveillance in the absence of culture. Here we describe a real-time molecular assay for detecting QRDR mutations in gonococci.

Antimicrobial activity of BMS 284756 (T-3811) against Neisseria gonorrhoeae tested by three methods

The potency of BMS 284756, a novel des-F(6)-quinolone, was tested against 137 clinical isolates of Neisseria gonorrhoeae including 50 strains observed to be resistant to ciprofloxacin and other newer quinolones. The gonococci were tested using NCCLS methods (agar dilution, disk diffusion) and Etest. BMS 284756 potency versus N. gonorrhoeae was generally two- to four-fold greater than ciprofloxacin. Penicillin resistance in the absence of ciprofloxacin resistance did not affect BMS 284756 activity. However, elevated ciprofloxacin MICs were associated with higher BMS 284756 MIC results as follows (BMS 284756 MIC(50)/MIC range in mg/l): ciprofloxacin-susceptible strains (0.016 or 0.03/0.004-0.06), ciprofloxacin-intermediate strains (0.06 or 0.12/0.008-0.25) and ciprofloxacin-resistant strains (0.12 or 0.5/0.12-1). Etest MICs were routinely lower than those produced by the reference agar dilution method, but the correlation coefficient remained acceptable (r = 0.87). Similarly acceptable correlation was achieved with 5 microg disk zone diameters (r = 0.78), where all zones were > or = 28 mm (MIC < or = 1 mg/l). In conclusion, BMS 284756 was very active against N. gonorrhoeae (MIC(50) 0.03 mg/l overall) including ciprofloxacin-resistant strains and could be considered as a single-dose therapeutic option for gonorrhoea.