Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 176
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Clin Microbiol ; 62(1): e0103923, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38084950

RESUMO

Supplementary nucleic acid amplification testing for Neisseria gonorrhoeae (NG) is widely used to circumvent specificity problems associated with extragenital sites. Here, we compared different supplementary approaches for confirming NG-positive samples from the cobas 4800 CT/NG (c4800) and cobas 6800 CT/NG (c6800) assays using the ResistancePlusGC (RP-GC) assay, which in addition to detecting NG, also predicts ciprofloxacin susceptibility via NG gyrA characterization. Two different nucleic acid extraction techniques were investigated for RP-GC detection; extracts from c4800 (c4800-RP-GC) and MagNA Pure 96 (MP96-RP-GC). NG-positive (n = 300) and -negative (n = 150) samples in cobas PCR media from routine c4800 testing were retrospectively retested with c4800, c6800, c4800-RP-GC, and MP96-RP-GC. Selected samples were also tested with Xpert CT/NG (Xpert) for discrepant analysis. The gyrA status was compared to ETEST ciprofloxacin susceptibility or non-susceptibility for recovered isolates (n = 63). Extragenital confirmatory rates were higher for MP96-RP-GC (131/140; 93.6%) compared to c4800-RP-GC (126/146; 86.3%), albeit not significantly (P = 0.6677). Of 9 samples testing positive by c6800 and negative by MP96-RP-GC, 7/9 (77.8%) were also negative by Xpert. By contrast, the number of samples returning a valid gyrA status was significantly (P = 0.0003) higher for MP96-RP-GC (270/293; 92.2%) compared to c4800-RP-GC (245/298; 82.2%). The overall MP96-RP-GC gyrA status correlated 98.4% (61/62) with the reported ciprofloxacin sensitive (35/36; 97.2%) or non-susceptible (26/26; 100%) phenotype. Improved RP-GC confirmatory rates and reported gyrA status were observed using MP96 nucleic acids compared to c4800 extracts. The data further highlight the ongoing need for NG supplemental testing for oropharyngeal samples.


Assuntos
Gonorreia , Ácidos Nucleicos , Humanos , Neisseria gonorrhoeae/genética , Ciprofloxacina/farmacologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Gonorreia/diagnóstico
2.
Epidemiol Infect ; 152: e8, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185832

RESUMO

Compared to cervical cancer, little is known about human papillomavirus (HPV)-driven oropharyngeal cancer and their cofactors. Here, we investigated potential associations between Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) with oral HPV and HPV persistence, which are known cofactors in cervical carcinogenesis, and also play a role in HPV-driven oropharyngeal cancer. Saliva samples (n = 547) from 312 people were tested for CT and NG and whom had previously been tested for oral HPV infection in a longitudinal study. Eight participants were positive for CT (2.6%) and one for NG (0.3%). Six of these nine participants were also positive for oral HPV in at least one of their samples. We found no significant associations between HPV, CT, or NG infection in the saliva samples analyzed. These preliminary data suggest CT and NG have little influence on oral HPV-positivity and persistence in a general population. However, larger studies focusing on 'at risk' population cohorts are necessary to assess potential associations between oral sexually transmissible infections and oral HPV infections, and their outcomes.


Assuntos
Coinfecção , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Neisseria gonorrhoeae , Chlamydia trachomatis , Coinfecção/epidemiologia , Estudos Longitudinais , Papillomavirus Humano
3.
Clin Infect Dis ; 76(12): 2187-2195, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722416

RESUMO

BACKGROUND: Although single nucleotide polymorphisms (SNPs) in Mycoplasma genitalium parC contribute to fluoroquinolone treatment failure, data are limited for the homologous gene, gyrA. This study investigated the prevalence of gyrA SNPs and their contribution to fluoroquinolone failure. METHODS: Samples from 411 patients (male and female) undergoing treatment for M. genitalium infection (Melbourne Sexual Health Centre, March 2019-February 2020) were analyzed by Sanger sequencing (gyrA and parC). For patients treated with moxifloxacin (n = 194), the association between SNPs and microbiologic treatment outcome was analyzed. RESULTS: The most common parC SNP was G248T/S83I (21.1% of samples), followed by D87N (2.3%). The most common gyrA SNP was G285A/M95I (7.1%). Dual parC/gyrA SNPs were found in 8.6% of cases. One third of infections harboring parC G248T/S83I SNP had a concurrent SNP in gyrA conferring M95I. SNPs in gyrA cooccurred with parC S83I variations. Treatment failure was higher in patients with parC S83I/gyrA dual SNPs when compared with infections with single S83I SNP alone from analysis of (1) 194 cases in this study (81.2% vs 45.8%, P = .047), and (2) pooled analysis of a larger population of 535 cases (80.6% vs 43.2%; P = .0027), indicating a strong additive effect. CONCLUSIONS: Compared with parC S83I SNP alone, M. genitalium infections with dual mutations affecting parC/gyrA had twice the likelihood of failing moxifloxacin. Although antimicrobial resistance varies by region globally, these data indicate that gyrA should be considered as a target for future resistance assays in Australasia. We propose a strategy for the next generation of resistance-guided therapy incorporating parC and gyrA testing.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Humanos , Masculino , Feminino , Moxifloxacina/uso terapêutico , Moxifloxacina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Mycoplasma genitalium/genética , Farmacorresistência Bacteriana/genética , Infecções por Mycoplasma/microbiologia , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Mutação , Macrolídeos/farmacologia
4.
Epidemiol Infect ; 151: e67, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37045547

RESUMO

We investigated the potential effects of COVID-19 public health restrictions on the prevalence and distribution of Neisseria gonorrhoeae (NG) genotypes in our Queensland isolate population in the first half of the year 2020. A total of 763 NG isolates were genotyped to examine gonococcal strain distribution and prevalence for the first 6 months of 2020, with 1 January 2020 to 31 March 2020 classified as 'pre' COVID-19 restrictions (n = 463) and 1 April 2020 to 30 June 2020 classified as 'post' COVID-19 restrictions (n = 300). Genotypes most prevalent 'pre' restrictions remained proportionally high 'post' restrictions, with some significantly increasing 'post' restrictions. However, genotype diversity was significantly reduced 'post' restrictions. Overall, it seems public health restrictions (9-10 weeks) were not sufficient to affect rates of infection or reduce the prevalence of well-established genotypes in our population, potentially due to reduced access to services or health-seeking behaviours.


Assuntos
COVID-19 , Gonorreia , Neisseria gonorrhoeae , Genótipo , Gonorreia/epidemiologia , Queensland/epidemiologia , Prevalência
5.
J Infect Dis ; 225(6): 983-993, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34894134

RESUMO

BACKGROUND: A gonococcal vaccine is urgently needed due to increasing gonorrhea incidence and emerging multidrug-resistant gonococcal strains worldwide. Men who have sex with men (MSM) have among the highest incidences of gonorrhea and may be a key target population for vaccination when available. METHODS: An individual-based, anatomical site-specific mathematical model was used to simulate Neisseria gonorrhoeae transmission in a population of 10 000 MSM. The impact of vaccination on gonorrhea prevalence was assessed. RESULTS: With a gonococcal vaccine of 100% or 50% protective efficacy, gonorrhea prevalence could be reduced by 94% or 62%, respectively, within 2 years if 30% of MSM are vaccinated on presentation for sexually transmitted infection (STI) testing. Elimination of gonorrhea is possible within 8 years with vaccines of ≥ 50% efficacy lasting 2 years, providing a booster vaccination is available every 3 years on average. A vaccine's impact may be reduced if it is not effective at all anatomical sites. CONCLUSIONS: Our study indicates that with a vaccine of modest efficacy and an immunization strategy that targets MSM presenting for STI screening, the prevalence of gonorrhea in this population could be rapidly and substantially reduced.


Assuntos
Gonorreia , Minorias Sexuais e de Gênero , Vacinas Bacterianas , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , Homossexualidade Masculina , Humanos , Incidência , Masculino , Neisseria gonorrhoeae
6.
Antimicrob Agents Chemother ; 66(5): e0027822, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35475636

RESUMO

Prevalence, trends, and treatment outcome estimates were generated for parC variants in macrolide-resistant Mycoplasma genitalium. Among 539 cases, the most common amino acid change was S83I, which increased from 13% in 2012 to 2013, to 23% in 2019 to 2020 (Ptrend = 0.046). From 381 moxifloxacin treatments, failure occurred in 58.7% (95% confidence interval [CI], 46.7 to 69.9) of cases with S83I. Other changes affecting S83 or D87 were uncommon and minor contributors to failure. The absence of S83I was highly predictive of moxifloxacin cure (96.4%; 95% CI, 93.7 to 98.2), highlighting diagnostic potential.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/uso terapêutico , Humanos , Macrolídeos , Moxifloxacina/uso terapêutico , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium/genética
7.
J Clin Microbiol ; 60(11): e0101222, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36314799

RESUMO

The application of direct metagenomic sequencing from positive blood culture broth may solve the challenges of sequencing from low-bacterial-load blood samples in patients with sepsis. Forty prospectively collected blood culture broth samples growing Gram-negative bacteria were extracted using commercially available kits to achieve high-quality DNA. Species identification via metagenomic sequencing and susceptibility prediction via a machine-learning algorithm (AREScloud) were compared to conventional methods and other rapid diagnostic platforms (Accelerate Pheno and blood culture identification [BCID] panel). A two-kit method (using MolYsis Basic and Qiagen DNeasy UltraClean kits) resulted in optimal extractions. Taxonomic profiling by direct metagenomic sequencing matched conventional identification in 38/40 (95%) samples. In two polymicrobial samples, a second organism was missed by sequencing. Prediction models were able to accurately infer susceptibility profiles for 6 common pathogens against 17 antibiotics, with an overall categorical agreement (CA) of 95% (increasing to >95% for 5/6 of the most common pathogens, if Klebsiella oxytoca was excluded). The performance of whole-genome sequencing (WGS)-antimicrobial susceptibility testing (AST) was suboptimal for uncommon pathogens (e.g., Elizabethkingia) and some ß-lactamase inhibitor antibiotics (e.g., ticarcillin-clavulanate). The time to pathogen identification was the fastest with BCID (1 h from blood culture positivity). Accelerate Pheno provided a susceptibility result in approximately 8 h. Illumina-based direct sequencing methods provided results in time frames similar to those of conventional culture-based methods. Direct metagenomic sequencing from blood cultures for pathogen detection and susceptibility prediction is feasible. Additional work is required to optimize algorithms for uncommon species and complex resistance genotypes as well as to streamline methods to provide more rapid results.


Assuntos
Hemocultura , Ácidos Nucleicos , Hemocultura/métodos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Fenótipo
8.
J Antimicrob Chemother ; 77(6): 1592-1599, 2022 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-35352120

RESUMO

BACKGROUND: Mycoplasma genitalium infection is a sexually transmitted infection that has rapidly become resistant to mainstay treatments. While individualized treatment approaches have been recommended and adopted for macrolides, individualized therapy for fluoroquinolones has not yet been explored, due to a lack of commercial molecular assays and a lack of confidence in specific mutations associated with resistance. In another recent study, we defined a clear role and diagnostic utility in focusing on the absence of resistance mutations to inform microbial cure with fluoroquinolone antimicrobials. METHODS: We developed two proof-of-concept molecular tests that focus on detection of M. genitalium and characterization of WT parC sequences that are strongly linked to fluoroquinolone susceptibility. RESULTS: We screened a total of 227 M. genitalium-positive samples using novel molecular beacon and dual hybridization probe assays. These assays were able to detect M. genitalium and characterize fluoroquinolone susceptibility in 143/227 (63%) samples, based on clear differences in melting peak temperatures. The results of these molecular assays were in 100% agreement with 'gold standard' Sanger sequencing. Additionally, WT parC sequences were readily distinguished from M. genitalium samples harbouring parC mutations of known or suspected clinical significance. The ability of the assays to successfully characterize fluoroquinolone susceptibility and resistance was reduced in low M. genitalium load samples. CONCLUSIONS: These proof-of-concept assays have considerable potential to improve individualized treatment approaches and rationalize tests of cure for M. genitalium infection. The ability to initiate individualized treatment in up to two-thirds of cases will enhance antimicrobial stewardship for this challenging pathogen.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Humanos , Macrolídeos/uso terapêutico , Mutação , Infecções por Mycoplasma/tratamento farmacológico , Mycoplasma genitalium/genética , Prevalência , RNA Ribossômico 23S/genética
9.
J Antimicrob Chemother ; 77(11): 2933-2936, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-35880750

RESUMO

OBJECTIVES: To develop instrument-free point-of-care methods using recombinase polymerase amplification (RPA) technology coupled with a simple lateral flow detection system to detect Neisseria gonorrhoeae and susceptibility to ciprofloxacin. METHODS: For identification of gonococcal infection, an RPA-based method was developed targeting the gonococcal porA pseudogene (NG-porA-RPA). For ciprofloxacin susceptibility, predictive WT sequences at codons 91 and 95 of the gonococcal gyrA DNase gene were targeted. Given the known complexities of SNP detection using RPA (e.g. the ability to accommodate mismatches) we trialled several different assays incorporating various additional non-template mismatches in the oligonucleotide sequences to reduce affinity for the mutant (resistant) gyrA sequences. Assays were evaluated using a bank of N. gonorrhoeae (n = 10) and non-gonococcal (n = 5) isolates and a panel of N. gonorrhoeae nucleic acid amplification test (NAAT)-positive clinical sample extracts (n = 40). RESULTS: The NG-porA-RPA assay was specific to N. gonorrhoeae and provided a positive percentage agreement (PPA) of 87.5% (35/40) compared with a commercial N. gonorrhoeae NAAT when applied to the 40 clinical sample extracts. For gyrA, the non-template bases successfully reduced banding intensity for double-mutant strains (mutations at both 91 and 95), but not for rarer single-mutant (91 only) strains. The most promising gyrA assay, NG-gyrA-RPA08, correctly detected 83% (25/30) of infections from NAAT-positive clinical samples confirmed to have WT gyrA sequences based on Sanger sequencing. CONCLUSIONS: These proof-of-concept data show that RPA technology has considerable promise for detecting N. gonorrhoeae and associated antibiotic susceptibility and would offer a diagnostic-based stewardship strategy identified as urgently needed by the WHO.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Humanos , Neisseria gonorrhoeae/genética , Ciprofloxacina/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Gonorreia/diagnóstico
10.
PLoS Comput Biol ; 17(11): e1009385, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34735428

RESUMO

The ability to treat gonorrhoea with current first-line drugs is threatened by the global spread of extensively drug resistant (XDR) Neisseria gonorrhoeae (NG) strains. In Australia, urban transmission is high among men who have sex with men (MSM) and importation of an XDR NG strain in this population could result in an epidemic that would be difficult and costly to control. An individual-based, anatomical site-specific mathematical model of NG transmission among Australian MSM was developed and used to evaluate the potential for elimination of an imported NG strain under a range of case-based and population-based test-and-treat strategies. When initiated upon detection of the imported strain, these strategies enhance the probability of elimination and reduce the outbreak size compared with current practice (current testing levels and no contact tracing). The most effective strategies combine testing targeted at regular and casual partners with increased rates of population testing. However, even with the most effective strategies, outbreaks can persist for up to 2 years post-detection. Our simulations suggest that local elimination of imported NG strains can be achieved with high probability using combined case-based and population-based test-and-treat strategies. These strategies may be an effective means of preserving current treatments in the event of wider XDR NG emergence.


Assuntos
Surtos de Doenças/prevenção & controle , Gonorreia/prevenção & controle , Homossexualidade Masculina , Modelos Biológicos , Austrália/epidemiologia , Biologia Computacional , Simulação por Computador , Surtos de Doenças/estatística & dados numéricos , Farmacorresistência Bacteriana Múltipla , Modelos Epidemiológicos , Gonorreia/epidemiologia , Gonorreia/microbiologia , Humanos , Masculino , Neisseria gonorrhoeae/efeitos dos fármacos , Prevalência
11.
Euro Surveill ; 27(18)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35514308

RESUMO

BackgroundEffective surveillance of antimicrobial resistance (AMR) in Neisseria gonorrhoeae is required for the early detection of resistant strains and to ensure that treatment guidelines are appropriate for the setting in which they are implemented. AMR in N. gonorrhoeae has been identified as a global health threat.AimWe performed a systematic review to identify and describe surveillance systems targeting AMR in N. gonorrhoeae.MethodsWe searched Medline, PubMed, Global Health, EMBASE, CINAHL, Web of Science and ProQuest databases and grey literature between 1 January 2012 and 27 September 2020. Surveillance systems were defined as the continuous, systematic collection, analysis and interpretation of N. gonorrhoeae resistance data. The key components of surveillance systems were extracted, categorised, described and summarised.ResultsWe found 40 publications reporting on N. gonorrhoeae AMR surveillance systems in 27 countries and 10 multi-country or global surveillance reports. The proportion of countries with surveillance systems in each of the WHO's six regions ranged from one of 22 countries in the Eastern Mediterranean and five of 54 in Africa, to three of 11 countries in South East Asia. Only four countries report systems which are both comprehensive and national. We found no evidence of a current surveillance system in at least 148 countries. Coverage, representativeness, volume, clinical specimen source, type and epidemiological information vary substantially and limit interpretability and comparability of surveillance data for public health action.ConclusionGlobally, surveillance for N. gonorrhoeae AMR is inadequate and leaves large populations vulnerable to a major public health threat.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Gonorreia/diagnóstico , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Humanos , Testes de Sensibilidade Microbiana
12.
Sex Health ; 19(4): 248-254, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35617973

RESUMO

Mycoplasma genitalium is an emerging sexually transmitted bacterium that is gaining attention because of the impact escalating antimicrobial resistance (AMR) is having on patient management. Of additional concern is that increased availability of testing appears to be resulting in screening practices that are not supported by clinical guidelines. This results in increasing numbers of asymptomatic M. genitalium infections being identified, which when combined with AMR issues, creates significant challenges for patients and clinicians. Rapidly rising levels of AMR, coupled with limited alternative treatment options, means patients can enter cycles of complex antimicrobial regimens that may cause more harm than the infection itself. In this review, we discuss the emergence of AMR and the implication for treatment practices, highlight the recommendations for testing but not screening for M. genitalium , and discuss expansion of individualised treatment strategies, to curb the emergence of resistance and improve outcomes for patients. We also provide suggestions for future research on the transmission and spread of resistance, to enhance global surveillance of this antimicrobial resistant pathogen and inform the revision of local and international treatment strategies.


Assuntos
Anti-Infecciosos , Infecções por Mycoplasma , Mycoplasma genitalium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Infecções Assintomáticas , Farmacorresistência Bacteriana , Humanos , Infecções por Mycoplasma/epidemiologia , Prevalência
13.
BMC Genomics ; 22(1): 474, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172000

RESUMO

BACKGROUND: Oxford Nanopore Technology (ONT) long-read sequencing has become a popular platform for microbial researchers due to the accessibility and affordability of its devices. However, easy and automated construction of high-quality bacterial genomes using nanopore reads remains challenging. Here we aimed to create a reproducible end-to-end bacterial genome assembly pipeline using ONT in combination with Illumina sequencing. RESULTS: We evaluated the performance of several popular tools used during genome reconstruction, including base-calling, filtering, assembly, and polishing. We also assessed overall genome accuracy using ONT both natively and with Illumina. All steps were validated using the high-quality complete reference genome for the Escherichia coli sequence type (ST)131 strain EC958. Software chosen at each stage were incorporated into our final pipeline, MicroPIPE. Further validation of MicroPIPE was carried out using 11 additional ST131 E. coli isolates, which demonstrated that complete circularised chromosomes and plasmids could be achieved without manual intervention. Twelve publicly available Gram-negative and Gram-positive bacterial genomes (with available raw ONT data and matched complete genomes) were also assembled using MicroPIPE. We found that revised basecalling and updated assembly of the majority of these genomes resulted in improved accuracy compared to the current publicly available complete genomes. CONCLUSIONS: MicroPIPE is built in modules using Singularity container images and the bioinformatics workflow manager Nextflow, allowing changes and adjustments to be made in response to future tool development. Overall, MicroPIPE provides an easy-access, end-to-end solution for attaining high-quality bacterial genomes. MicroPIPE is available at https://github.com/BeatsonLab-MicrobialGenomics/micropipe .


Assuntos
Escherichia coli , Genoma Bacteriano , Biologia Computacional , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Fluxo de Trabalho
14.
J Clin Microbiol ; 59(5)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33658263

RESUMO

Resistance-guided therapy (RGT) for gonorrhea may reduce unnecessary use of broad-spectrum antibiotics. When reflexed from the Aptima Combo 2 assay, the ResistancePlus GC assay demonstrated 94.8% sensitivity and 100.0% specificity for Neisseria gonorrhoeae detection. Of the 379 concordant N. gonorrhoeae-positive samples, 86.8% were found to possess the gyrA S91F mutation, which was highly predictive for ciprofloxacin resistance and stable across 3,144 publicly available N. gonorrhoeae genomes. Our work supports the feasibility of implementing RGT for gonorrhea into routine molecular workflows.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana , Gonorreia/diagnóstico , Gonorreia/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/genética , Reflexo
15.
J Antimicrob Chemother ; 76(4): 887-892, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33448305

RESUMO

BACKGROUND: Mycoplasma genitalium was recently added to the CDC's antimicrobial resistance threats 'watch list', as it has rapidly become resistant to mainstay treatments. In Australia, treatment failure with fluoroquinolones remain commonplace, even when Sanger sequencing fails to identify evidence of resistance mutations. METHODS: Suspecting that Sanger sequencing may miss low-load mixed infections, we applied three additional PCR-based approaches (allele-specific primer-based PCR, probe-based PCR and amplicon deep sequencing) to detect mutations associated with fluoroquinolone susceptibility/resistance. We focused on resistance mutations at amino acid positions 83 and 87 of parC, as these were previously shown to be common in Australia. RESULTS: Our results showed evidence of mixtures of fluoroquinolone-susceptible and -resistant strains in up to 27/423 samples (6.4%). These included 1 sample that was indicated to be mixed by Sanger sequencing and all three additional PCR methods, 6 samples detected by two or more of the additional PCRs but not by Sanger sequencing and finally 20 samples that were detected by only one of the additional PCR methods. A key question was whether Sanger sequencing failed to detect fluoroquinolone resistance in any samples; overall, we observed that Sanger sequencing failed to detect fluoroquinolone resistance in up to 3.8% (16/423) of samples. CONCLUSIONS: The presence of mixed susceptibility infections may have important implications for clinical patient management and stresses the need for appropriate detection of resistance and selection of antimicrobials to ensure appropriate treatment of M. genitalium infections.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Austrália , Farmacorresistência Bacteriana , Fluoroquinolonas/farmacologia , Humanos , Macrolídeos , Mutação , Infecções por Mycoplasma/tratamento farmacológico , Mycoplasma genitalium/genética , RNA Ribossômico 23S
16.
Eur J Clin Microbiol Infect Dis ; 40(1): 67-75, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32767178

RESUMO

Supplementary nucleic acid amplification tests for Neisseria gonorrhoeae (NG) are widely used to circumvent specificity problems often associated with extragenital sites. This study was prompted by our observations and concerns from local sexual health physicians over increased discrepancies between Roche cobas 4800 CT/NG (c4800) and our in-house supplementary NG-PCR (NG-duplex) for oropharyngeal samples, when compared with Abbott RealTime CT/NG (m2000) performed prior. Here, we investigated these differences. Three banks of NG-positive samples were used. Bank 1 (n = 344) were screened using m2000. Banks 2 (n = 344) and 3 (n = 400) were screened using c4800. Remnant nucleic acids from all banks were tested using NG-duplex as part of routine testing. Bank 2 samples were further tested using m2000, some selectively tested using Cepheid Xpert CT/NG. Bank 3 samples were further tested using cobas CT/NG (cobas 6800 system). Confirmatory rates were significantly (p < 0.0001) higher for m2000 compared with c4800, with oropharyngeal samples the key difference. However, we also showed that our NG-duplex failed to confirm some true-positive NG samples. Using an expanded gold standard, confirmatory rates for m2000 and c4800 exceeded 90% for all anatomical sites with the exception of c4800 for oropharyngeal specimens at 78%. The observed discrepancies were due to a combination of c4800 producing false-positive results for oropharyngeal samples as well as sensitivity issues related to the NG-duplex assay. The data highlight the ongoing need for NG supplemental nucleic acid testing for oropharyngeal samples but also emphasise the need for careful selection of supplementary methods.


Assuntos
Gonorreia/diagnóstico , Neisseria gonorrhoeae/genética , Gonorreia/microbiologia , Humanos , Técnicas de Amplificação de Ácido Nucleico , Orofaringe/microbiologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
17.
Eur J Clin Microbiol Infect Dis ; 40(11): 2447-2453, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33974185

RESUMO

Carbapenemase-producing organisms (CPOs) pose a serious clinical threat and rapid detection tools are essential to aid in patient management. We developed rapid and simple molecular tests to detect blaNDM-type and blaVIM-type carbapenemase genes using recombinase polymerase amplification (RPA) combined with a lateral flow detection. The tests could provide results in approximately 15 min when using DNA extracts, with limits of detection of 9.2 copies/µl for the blaNDM-type assay and 7.5 copies/µl for blaVIM-type assay, and successfully detected all isolates harbouring the carbapenemase encoding genes in a panel of 57 isolates. These RPA tests may be suitable for use in low-resource settings to tailor rapid implementation of infection control precautions and antibiotic stewardship.


Assuntos
Bactérias/enzimologia , Proteínas de Bactérias/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , beta-Lactamases/genética , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Proteínas de Bactérias/metabolismo , Primers do DNA/genética , Farmacorresistência Bacteriana , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Recombinases/metabolismo , beta-Lactamases/metabolismo
18.
Clin Infect Dis ; 71(5): 1324-1326, 2020 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31848594

RESUMO

An accurate rotavirus diagnosis is important for clinical management and monitoring active disease and vaccine effectiveness. Between 2016-2018, rotavirus-positive results in our laboratory were from vaccine virus shedding in 71/152 (46.7%) infants with a request for rotavirus testing. Routine infant diagnostic testing should ideally distinguish vaccine from wild-type viruses.


Assuntos
Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Vírus da Varíola Bovina , Fezes , Humanos , Lactente , Uso Excessivo dos Serviços de Saúde , Rotavirus/genética , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/prevenção & controle , Vacinas Atenuadas
19.
Sex Health ; 17(4): 359-367, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32731917

RESUMO

Background The advent of fully automated nucleic acid amplification test (NAAT) technology brings new public health opportunities to provide Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) point-of-care testing (POCT) in non-traditional settings. METHODS: This pilot study evaluated the integration of the CT/NG Xpert diagnostic assay into an urban peer-led community setting providing HIV and syphilis POCT. A comprehensive protocol of testing, result notification, referral and follow up, managed by peer test facilitators, was undertaken. RESULTS: Over 67 weeks, there were 4523 occasions of CT/NG testing using urine, oropharyngeal and anorectal samples with 25.7% (803) of the 3123 unique participants returning for repeat testing. The prevalence of CT and NG was 9.5% and 5.4% respectively. Where CT and or NG infection was detected, 98.4% (604/614) of participants were successfully notified of detected infection and referred for treatment. Evaluation Survey responses (11.4%, 516/4523) indicated a substantial proportion of respondents (27.1%, 140/516) 'would not have tested anywhere else'. Of note, 17.8% (92/516) of participants reported no previous CT/NG test and an additional 17.8% (92/516) reported testing more than 12 months ago. A total of 95.9% (495/516) of participants 'Strongly agreed' or 'Agreed' to being satisfied with the service. CONCLUSION: The project successfully demonstrated an acceptable and feasible model for a peer-delivered community-led service to provide targeted molecular CT/NG POCT. This model offers capacity to move beyond the traditional pathology and STI testing services and establish community-led models that build trust and increase testing rates for key populations of epidemiological significance.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis , Centros Comunitários de Saúde , Gonorreia/diagnóstico , Neisseria gonorrhoeae , Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Imediatos , Adulto , Austrália/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação do Paciente , Projetos Piloto , População Urbana
20.
Sex Health ; 17(1): 15-21, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31945307

RESUMO

Background The aim of this study was to compare the performance of pooled self-collected urogenital, pharyngeal and anorectal specimens to that of individual specimen results for the molecular detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) near the point of care (POC) for diagnostic sensitivity. METHODS: Clients (mostly men who have sex with men) attending an urban community testing service and three sex-on-premises venues in Brisbane, Australia, were offered CT and NG testing by trained lay providers. Participants provided three self-collected specimens (urine, pharyngeal and rectal) for testing by GeneXpert (Cepheid, Sunnyvale, CA, USA). If any of the individual specimens from a participant were positive, all three specimens were pooled and retested. RESULTS: Of the 388 participants who provided three individual anatomical specimens, 76 (19.6%) were found to be positive for CT and/or NG at one or more sites. The pooling approach failed to detect five CT rectal and four NG pharyngeal infections. The overall performance (sensitivity) of the pooling approach compared with individual specimen testing and Cohen's κ were 90.0% and 0.86 respectively for CT and 89.7% and 0.89 respectively for NG. CONCLUSIONS: Reduced sensitivity was observed when using pooled specimens for the detection of CT and NG using GeneXpert near the POC, similar to results reported in laboratory-based CT and NG pooling studies. These data suggest specimen pooling is feasible near to the POC, potentially saving time and costs when screening at-risk populations for CT and NG. Our data also suggest a reduction in pooled urine could improve overall test sensitivity.


Assuntos
Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/urina , Gonorreia/diagnóstico , Gonorreia/urina , Homossexualidade Masculina/estatística & dados numéricos , Programas de Rastreamento/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Manejo de Espécimes/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Chlamydia trachomatis/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Neisseria gonorrhoeae/isolamento & purificação , Doenças Faríngeas/microbiologia , Sistemas Automatizados de Assistência Junto ao Leito , Doenças Retais/microbiologia , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA