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González-Fernández MD, Escarcega-Tame MA, López-Hurtado M, Flores-Salazar VR, Escobedo-Guerra MR, Giono-Cerezo S, Guerra-Infante FM. Identification of Chlamydia trachomatis genotypes in newborns with respiratory distress. An Pediatr (Barc) 2023:S2341-2879(23)00101-1. [PMID: 37169687 DOI: 10.1016/j.anpede.2023.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/30/2023] [Indexed: 05/13/2023] Open
Abstract
INTRODUCTION One hundred thirty million Chlamydia trachomatis infections are reported worldwide each year. Nineteen serotypes of this pathogen can cause infection in pregnant women and neonates. The distribution of these genotypes in newborns with respiratory infections in Mexico is unknown. MATERIAL AND METHODS We tested 1062 bronchial lavage samples from neonates with respiratory distress syndrome for Chlamydia infection. The diagnosis of Chlamydia was made by plasmid detection with an in-house PCR assay, and genotypes were identified using a PCR-RFLP assay for the ompA gene. RESULTS The genotyping of 40 strains identified 14 as I/Ia (35%), 13 as E (32.5%), 7 as D (17.5%), 5 as F (12.5%), and 1 as L2 (2.5%). The relative risk analysis showed that genotype D was associated with neonatal sepsis (RR, 5.83; 95% confidence interval [CI], 1.51-25.985; P < .02), while the I/Ia genotype was significantly associated with chorioamnionitis in the mother (2.8; 95% CI, 1.4-5.5; P < .05). CONCLUSIONS Although C. trachomatis genotypes I/Ia and E of were the strains involved most frequently in respiratory infections in Mexican neonates, 80% of patients with genotype F developed respiratory disease. In contrast, genotype D was associated with neonatal sepsis, and genotype I/Ia with chorioamnionitis.
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Affiliation(s)
- Melissa D González-Fernández
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
| | - Marco A Escarcega-Tame
- Laboratorio de Virología, Instituto Nacional de Perinatología, Ciudad de México, Mexico.
| | - Marcela López-Hurtado
- Laboratorio de Virología, Instituto Nacional de Perinatología, Ciudad de México, Mexico.
| | | | | | - Silvia Giono-Cerezo
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
| | - Fernando M Guerra-Infante
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico; Laboratorio de Virología, Instituto Nacional de Perinatología, Ciudad de México, Mexico.
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Zhao J, Shui J, Luo L, Ao C, Lin H, Liang Y, Wang L, Wang H, Chen H, Tang S. Identification and characterization of mixed infections of Chlamydia trachomatis via high-throughput sequencing. Front Microbiol 2022; 13:1041789. [PMID: 36439830 PMCID: PMC9687396 DOI: 10.3389/fmicb.2022.1041789] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022] Open
Abstract
Precise genotyping is necessary to understand epidemiology and clinical manifestations of Chlamydia trachomatis infection with different genotypes. Next-generation high-throughput sequencing (NGHTS) has opened new frontiers in microbial genotyping, but has been clinically characterized in only a few settings. This study aimed to determine C. trachomatis genotypes in particular mixed-genotype infections and their association with clinical manifestations and to characterize the sensitivity and accuracy of NGHTS. Cervical specimens were collected from 8,087 subjects from physical examination center (PEC), assisted reproductive technology center (ART) and gynecology clinics (GC) of Chenzhou Hospital of China. The overall prevalence of C. trachomatis was 3.8% (311/8087) whereas a prevalence of 2.8, 3.7 and 4.8% was found in PEC, ART and GC, respectively. The most frequent three C. trachomatis genotypes were E (27.4%, 83/303), F (21.5%, 65/303) and J (18.2%, 55/303). Moreover, NGHTS identified 20 (6.6%, 20/303) mixed-genotype infections of C. trachomatis. Genotype G was more often observed in the subjects with pelvic inflammatory disease than genotype E (adjusted OR = 3.61, 95%CI, 1.02-12.8, p = 0.046). Mixed-genotype infection was associated with severe vaginal cleanliness (degree IV) with an adjusted OR of 5.17 (95%CI 1.03-25.9, p = 0.046) whereas mixed-genotype infection with large proportion of minor genotypes was associated with cervical squamous intraepithelial lesion (SIL) with an adjusted OR of 5.51 (95%CI 1.17-26.01, p = 0.031). Our results indicated that NGHTS is a feasible tool to identity C. trachomatis mixed-genotype infections, which may be associated with worse vaginal cleanliness and cervical SIL.
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Affiliation(s)
- Jianhui Zhao
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jingwei Shui
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Lipei Luo
- Department of Clinical Microbiology Laboratory, Chenzhou No. 1 People’s Hospital, Chenzhou, China
| | - Cailing Ao
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Hongqing Lin
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yuanhao Liang
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Li Wang
- Department of Clinical Microbiology Laboratory, Chenzhou No. 1 People’s Hospital, Chenzhou, China
| | - Haiying Wang
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Hongliang Chen
- Department of Clinical Microbiology Laboratory, Chenzhou No. 1 People’s Hospital, Chenzhou, China
| | - Shixing Tang
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
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Molano M, Tabrizi SN, Phillips S, Danielewski J, Cornall A, Morre SA, Garland SM. Development of a rapid colorimetric multiplex PCR-reverse line blot for the detection and typing of 14 Chlamydia trachomatis genovars. J Med Microbiol 2018; 67:1560-1570. [PMID: 30303481 DOI: 10.1099/jmm.0.000836] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE Chlamydia trachomatis is responsible for trachoma-associated blindness as well as the most common sexually transmitted bacterial infection worldwide, although the genovars for the former are typically A-C, whilst for the latter they are D-K and for the uncommon infection lymphogranuloma venereum they are L1-3. Nucleotide variations within the ompA gene facilitate the identification of C. trachomatis genovars. This study describes a colorimetric multiplex PCR/RLB typing assay (mPCR-RLB) directed to the VD2 region of the ompA gene for general C. trachomatis positivity and the identification of 14 individual C. trachomatis genovars. METHODOLOGY The assay was validated by analysing 40 blinded samples that included reference strains of C. trachomatis genovars and other non-chlamydial micro-organisms that had been analysed previously using quantitative PCR (qPCR). Ninety clinical samples that had previously been found to be C. trachomatis-positive by qPCR were also evaluated using the mPCR-RLB assay. RESULTS The mPCR-RLB assay showed 100 % agreement with the qPCR in the detection of C. trachomatis reference strains and no cross-reaction of non-chlamydial micro-organisms was observed. In the analysis of the chlamydial clinical samples, 97.8 % were C. trachomatis-positive by mPCR/RLB assay and there was a 96.6 % concordance with the qPCR at the group identification level and a 92.2 % concordance at the genovar level. CONCLUSION The mPCR-RLB assay is a rapid and sensitive methodology for the identification of C. trachomatis genovars associated with urogenital infections, trachoma or lymphogranuloma venereum diseases that can be implemented in clinical settings, helping to identify reinfections and treatment failures and establish the appropriate treatment course.
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Affiliation(s)
- Monica Molano
- 1Regional HPV Labnet Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, Victoria, Australia
| | - Sepehr N Tabrizi
- 3Department of Obstetrics and Gynaecology, University of Melbourne, Australia
- 2Murdoch Children's Research Institute, Parkville, Victoria, Australia
- 1Regional HPV Labnet Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, Victoria, Australia
| | - Samuel Phillips
- 2Murdoch Children's Research Institute, Parkville, Victoria, Australia
- 1Regional HPV Labnet Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, Victoria, Australia
| | - Jennifer Danielewski
- 2Murdoch Children's Research Institute, Parkville, Victoria, Australia
- 1Regional HPV Labnet Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, Victoria, Australia
| | - Alyssa Cornall
- 3Department of Obstetrics and Gynaecology, University of Melbourne, Australia
- 2Murdoch Children's Research Institute, Parkville, Victoria, Australia
- 1Regional HPV Labnet Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, Victoria, Australia
| | - Servaas A Morre
- 5Department of Genetics and Cell Biology, Research School Oncology and Developmental Biology (GROW), Institute for Public Health Genomics, University of Maastricht, Maastricht, The Netherlands
- 4Department of Medical Microbiology and Infection Control, Laboratory of Immunogenetics, VU University Medical Centre, Amsterdam, The Netherlands
| | - Suzanne M Garland
- 3Department of Obstetrics and Gynaecology, University of Melbourne, Australia
- 2Murdoch Children's Research Institute, Parkville, Victoria, Australia
- 1Regional HPV Labnet Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, Victoria, Australia
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Gharsallah H, Frikha-Gargouri O, Bom RJ, Hammami A, Bruisten SM. Comparison of reverse hybridization and ompA sequencing methods applied on Chlamydia trachomatis strains from Tunisia. Microbiologyopen 2017; 7:e00549. [PMID: 29282889 PMCID: PMC5911986 DOI: 10.1002/mbo3.549] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 08/22/2017] [Accepted: 09/04/2017] [Indexed: 12/14/2022] Open
Abstract
Two techniques based on ompA amplification of Chlamydia trachomatis were compared, being reverse hybridization (RHM) and ompA sequencing (OSA), to investigate the concordance between them and to study the epidemiological relevance of each method. In addition, phylogenetic analysis was performed on the ompA sequences. One hundred and seven C. trachomatis positive samples from Tunisian patients and female sex workers were analyzed using both the RHM and ompA sequencing. The overall genovar distribution obtained with both techniques was very similar. The RHM identified nine genovars, being B, D, E, F, G, H, I, J and K, where B, I, J, and K were only found in mixed infections versus 7 types for the OSA being D, E, F, G, H, I, and K. The agreement between both typing techniques was 87.8%. Both methods showed that genovar E was the most predominant type. In 24.3% of the analyzed samples, mixed infections were detected. In 96.1% of these, the genovar identified by OSA was also detected using the RHM. OmpA sequencing allowed determination of six genovar types that could not be typed using RHM. The analyses of ompA nucleotide variation in the 107 clinical specimens detected ompA genovar variants with distinct ompA mutational patterns for types D2, G1, G2, and H1. In conclusion, RHM and OSA showed a high agreement in C. trachomatis genotyping results with each having their specific benefits.
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Affiliation(s)
- Houda Gharsallah
- Department of Microbiology and research laboratory "Microorganismes et Pathologies Humaines", Habib Bourguiba university hospital, Medical School of Sfax, University of Sfax, Sfax, Tunisia
| | - Olfa Frikha-Gargouri
- Biopesticides Laboratory, Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia
| | - Reinier J Bom
- Public Health Laboratory, The Netherlands Condomerie, Cluster Infectious Diseases, Public Health Service Amsterdam, Amsterdam, The Netherlands
| | - Adnene Hammami
- Department of Microbiology and research laboratory "Microorganismes et Pathologies Humaines", Habib Bourguiba university hospital, Medical School of Sfax, University of Sfax, Sfax, Tunisia
| | - Sylvia M Bruisten
- Public Health Laboratory, Public Health Service of Amsterdam (GGD Amsterdam), Amsterdam, the Netherlands
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5
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Xue Y, Zheng H, Tang W, Mai Z, Huang J, Huang S, Qin X, Chen L, Zheng L. Prevalence and Genotype Distribution of Chlamydia trachomatis in Urine among Men Attending Sexually Transmitted Disease Clinics in Guangdong Province, China, in 2016. Jpn J Infect Dis 2017; 71:104-108. [PMID: 29279452 DOI: 10.7883/yoken.jjid.2017.358] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Studies have rarely assessed the genotype distribution of Chlamydia trachomatis (CT) in urine among men attending sexually transmitted disease clinics (MSCs) in China. This study was aimed at investigating the prevalence and molecular epidemiology of CT infection by examining urine samples among MSCs from different geographic areas of Guangdong Province, China. A cross-sectional study was conducted among MSCs from 10 human immunodeficiency virus sentinel surveillance sites in Guangdong Province. CT DNA was extracted from male urine samples and analyzed using a Roche cobas 4800 CT/NG. The ompA genes were amplified by nested PCR and sequenced. The leukocyte esterase test was performed by routine urine analysis at local clinics. Of the 1,903 samples, 163 (8.6%, 95% confidence interval [CI] 3.8-16.3%) tested positive for CT. The highest prevalence (10.5%) of CT infection was observed among participants aged between 21 and 30 years. A total of 130 CT-positive samples (79.8%, 130/163) were successfully genotyped by nested PCR, resulting in 8 genotypes. The most prevalent genotypes were D, E, F, and J, with proportions of 20.8%, 20.0%, 17.7%, and 16.9%, respectively. There were no significant correlations between the geographical areas, leukocyte esterase test results and genotype distribution. Promotion of detection and molecular epidemiology research is needed for effective and comprehensive prevention and control programs.
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Affiliation(s)
- Yaohua Xue
- Department of Clinical Laboratory, Nanfang Hospital, Southern Medical University/ The First School of Clinical Medicine, Southern Medical University.,Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Heping Zheng
- Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Weiming Tang
- SESH Research Team at the School of Medicine, University of North Carolina at Chapel Hill Project-China
| | - Zhida Mai
- Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Jinmei Huang
- Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Shujie Huang
- Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Xiaolin Qin
- Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Lei Chen
- Department of Research Center, Dermatology Hospital, Southern Medical University/Guangdong Provincial Dermatology Hospital
| | - Lei Zheng
- Department of Clinical Laboratory, Nanfang Hospital, Southern Medical University/ The First School of Clinical Medicine, Southern Medical University
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6
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Michael Dunne W, Pouseele H, Monecke S, Ehricht R, van Belkum A. Epidemiology of transmissible diseases: Array hybridization and next generation sequencing as universal nucleic acid-mediated typing tools. INFECTION GENETICS AND EVOLUTION 2017; 63:332-345. [PMID: 28943408 DOI: 10.1016/j.meegid.2017.09.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Revised: 09/14/2017] [Accepted: 09/15/2017] [Indexed: 02/05/2023]
Abstract
The magnitude of interest in the epidemiology of transmissible human diseases is reflected in the vast number of tools and methods developed recently with the expressed purpose to characterize and track evolutionary changes that occur in agents of these diseases over time. Within the past decade a new suite of such tools has become available with the emergence of the so-called "omics" technologies. Among these, two are exponents of the ongoing genomic revolution. Firstly, high-density nucleic acid probe arrays have been proposed and developed using various chemical and physical approaches. Via hybridization-mediated detection of entire genes or genetic polymorphisms in such genes and intergenic regions these so called "DNA chips" have been successfully applied for distinguishing very closely related microbial species and strains. Second and even more phenomenal, next generation sequencing (NGS) has facilitated the assessment of the complete nucleotide sequence of entire microbial genomes. This technology currently provides the most detailed level of bacterial genotyping and hence allows for the resolution of microbial spread and short-term evolution in minute detail. We will here review the very recent history of these two technologies, sketch their usefulness in the elucidation of the spread and epidemiology of mostly hospital-acquired infections and discuss future developments.
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Affiliation(s)
- W Michael Dunne
- Data Analytics Unit, bioMerieux, 100 Rodolphe Street, Durham, NC 27712, USA.
| | - Hannes Pouseele
- Data Analytics Unit, bioMerieux, 100 Rodolphe Street, Durham, NC 27712, USA; Applied Maths NV, Keistraat 120, 9830 Sint-Martens-Latem, Belgium.
| | - Stefan Monecke
- Alere Technologies GmbH, Jena, Germany; InfectoGnostics Research Campus, Jena, Germany; Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Dresden, Germany
| | - Ralf Ehricht
- Alere Technologies GmbH, Jena, Germany; InfectoGnostics Research Campus, Jena, Germany.
| | - Alex van Belkum
- Data Analytics Unit, bioMérieux, 3, Route de Port Michaud, 38390 La Balme Les Grottes, France.
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Köksal MO, Beka H, Demirci M, Kadioglu A, Agacfidan A, Akgül B. Prevalence and genotyping of Chlamydia trachomatis in symptomatic male patients from Istanbul, Turkey. SPRINGERPLUS 2016; 5:1706. [PMID: 27795880 PMCID: PMC5050182 DOI: 10.1186/s40064-016-3370-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 09/23/2016] [Indexed: 11/10/2022]
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8
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Andersson P, Harris SR, Smith HMBS, Hadfield J, O'Neill C, Cutcliffe LT, Douglas FP, Asche LV, Mathews JD, Hutton SI, Sarovich DS, Tong SYC, Clarke IN, Thomson NR, Giffard PM. Chlamydia trachomatis from Australian Aboriginal people with trachoma are polyphyletic composed of multiple distinctive lineages. Nat Commun 2016; 7:10688. [PMID: 26912299 PMCID: PMC4773424 DOI: 10.1038/ncomms10688] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 01/07/2016] [Indexed: 01/29/2023] Open
Abstract
Chlamydia trachomatis causes sexually transmitted infections and the blinding disease trachoma. Current data on C. trachomatis phylogeny show that there is only a single trachoma-causing clade, which is distinct from the lineages causing urogenital tract (UGT) and lymphogranuloma venerum diseases. Here we report the whole-genome sequences of ocular C. trachomatis isolates obtained from young children with clinical signs of trachoma in a trachoma endemic region of northern Australia. The isolates form two lineages that fall outside the classical trachoma lineage, instead being placed within UGT clades of the C. trachomatis phylogenetic tree. The Australian trachoma isolates appear to be recombinants with UGT C. trachomatis genome backbones, in which loci that encode immunodominant surface proteins (ompA and pmpEFGH) have been replaced by those characteristic of classical ocular isolates. This suggests that ocular tropism and association with trachoma are functionally associated with some sequence variants of ompA and pmpEFGH. Chlamydia trachomatis isolates causing a blinding disease (trachoma) form a single lineage that is different from the lineages causing urogenital infections. Here, Andersson et al. show however that trachoma isolates from Australia are more closely related to urogenital strains than to other trachoma isolates.
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Affiliation(s)
- Patiyan Andersson
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia
| | - Simon R Harris
- Pathogen Variation Programme, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Helena M B Seth Smith
- Pathogen Variation Programme, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK.,Functional Genomics Centre Zürich, University of Zurich, Zurich CH-8057, Switzerland.,Institute for Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich CH-8057, Switzerland
| | - James Hadfield
- Pathogen Variation Programme, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Colette O'Neill
- Department of Clinical and Experimental Science, Molecular Microbiology Group, University Medical School, Southampton General Hospital, Southampton SO16 6YD, UK
| | - Lesley T Cutcliffe
- Department of Clinical and Experimental Science, Molecular Microbiology Group, University Medical School, Southampton General Hospital, Southampton SO16 6YD, UK
| | - Fiona P Douglas
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia
| | - L Valerie Asche
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia
| | - John D Mathews
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia.,School of Population and Global Health, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Susan I Hutton
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia
| | - Derek S Sarovich
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia
| | - Steven Y C Tong
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia
| | - Ian N Clarke
- Department of Clinical and Experimental Science, Molecular Microbiology Group, University Medical School, Southampton General Hospital, Southampton SO16 6YD, UK
| | - Nicholas R Thomson
- Pathogen Variation Programme, The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK.,Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Philip M Giffard
- Global and Tropical Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, Casuarina, Northern Territory 0811, Australia.,School of Psychological and Clinical Sciences, Charles Darwin University, Casuarina, Northern Territory 0811, Australia
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9
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Association of the in vitro susceptibility of clinical isolates of chlamydia trachomatis with serovar and duration of antibiotic exposure. Sex Transm Dis 2015; 42:115-9. [PMID: 25668641 DOI: 10.1097/olq.0000000000000241] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The presence of persistent Chlamydia trachomatis infection after treatment does not always correlate with in vitro susceptibility testing. METHODS The in vitro minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of azithromycin, clarithromycin, roxithromycin, doxycycline, tetracycline, ofloxacin, and penicillin were tested against 61 clinical isolates of C. trachomatis on 6 serovars, and the MIC/MBC of azithromycin and ofloxacin at different points in time after antibiotic administration to infected cultures. RESULTS Of the 7 antibiotics tested, clarithromycin showed the greatest activity against C. trachomatis isolates with MIC90 of 0.032 μg/mL and MBC90 of 0.064 μg/mL, followed by doxycycline with MIC90 0.064 μg/mL and MBC90 0.064 μg/mL, and azithromycin with MIC90 0.160 μg/mL and MBC90 0.320 μg/mL. Azithromycin had roughly the same MIC50 values (0.08 μg/mL) as the other serovars isolates tested, and other antibiotics showed a 2- to 4-fold difference in MICs50 between serovars. In addition, an increase in the azithromyin MIC was observed by 8 hours and the ofloxacin MIC by 16 hours. At 24 hours, the azithromycin MICs were greater than 40 μg/mL and ofloxacin MICs were greater than 64 μg/mL. CONCLUSIONS The current data demonstrated that the antimicrobial susceptibility of C. trachomatis was influenced by both the serovar type and the duration of exposure to antibiotics in infected cultures.
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High-resolution typing reveals distinct Chlamydia trachomatis strains in an at-risk population in Nanjing, China. Sex Transm Dis 2014; 40:647-9. [PMID: 23859913 DOI: 10.1097/01.olq.0000431355.73217.df] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We investigated Chlamydia trachomatis strains from Nanjing, China, and whether these strains differed from Amsterdam, the Netherlands. C. trachomatis type was determined with multilocus sequence typing. Most strains were specific to Nanjing, but some clustered with strains from Amsterdam. This demonstrates a geographical variation in C. trachomatis previously left undetected.
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Gharsallah H, Frikha-Gargouri O, Sellami H, Besbes F, Znazen A, Hammami A. Chlamydia trachomatis genovar distribution in clinical urogenital specimens from Tunisian patients: high prevalence of C. trachomatis genovar E and mixed infections. BMC Infect Dis 2012. [PMID: 23198910 PMCID: PMC3573954 DOI: 10.1186/1471-2334-12-333] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background This epidemiological study was carried out in Sfax (south of Tunisia) and focused on genital Chlamydia trachomatis (C. trachomatis) genovar distribution. Methods One hundred and thirty seven genital samples from 4067 patients (4.2%) attending the Habib Bourguiba University hospital of Sfax over 12 years (from 2000 to 2011) were found to be C. trachomatis PCR positive by the Cobas Amplicor system. These samples were genotyped by an in house reverse hybridization method. Results One hundred and eight (78.8%) samples contained only one genovar and 29 (21.2%) samples contained two or three genovars. Genovar E was the most prevalent (70.8%) single genovar and it was detected in 90.6% of all the cases. Genovars J, C and L1-L3 were not detected in our samples whereas ocular genovars A and B were in 5 cases. All the five cases were mixed infections. Men had more mixed infections than women (p=0.02) and were more frequently infected by genovars F and K (p<0.05). No associations between current infection, infertility and the genovar distribution were observed. Patients coinfected with Neisseria gonorrhoeae were also significantly more frequently infected with mixed genovars (p=0.04). Conclusions In conclusion, we have reported a high prevalence of genovar E and of mixed infections in our study population. Such data could have implications for the control and vaccine development of C. trachomatis in Tunisia.
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Affiliation(s)
- Houda Gharsallah
- Department of Microbiology and research laboratory Microorganismes et Pathologie Humaine, Habib Bourguiba university hospital, medical school of Sfax, University of Sfax, Sfax, Tunisia
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Gharsallah H, Frikha-Gargouri O, Besbes F, Sellami H, Znazen A, Hammami A. Development and application of an in-house reverse hybridization method for Chlamydia trachomatis genotyping. J Appl Microbiol 2012; 113:846-55. [PMID: 22738848 DOI: 10.1111/j.1365-2672.2012.05375.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 05/30/2012] [Accepted: 06/17/2012] [Indexed: 11/28/2022]
Abstract
AIM To develop and evaluate an in-house reverse hybridization technique for Chlamydia trachomatis genotype identification. METHODS AND RESULTS The evaluation of the developed and optimized reverse hybridization method on reference strains showed the specific detection of all genotypes. This technique showed its ability to type one inclusion-forming unit of C. trachomatis genotype E and equivalent sensitivity to the Cobas TaqMan assay. It was also able to detect mixed infections in vitro. Application of the reverse hybridization method on 38 isolated C. trachomatis strains and their respective swabs allowed the detection of six urogenital genotypes D, E, F, G, H and K and one trachoma genotype B. Genotype E was the most prevalent, detected in 73% of the swab samples. Mixed infections were detected in 26% of swab cases. CONCLUSION The reverse hybridization technique is simple and does not require specialized instruments. It is powerful in the diagnosis of mixed infections and is suitable for use in epidemiological studies. SIGNIFICANCE AND IMPACT OF THE STUDY This technique allowed rapid C. trachomatis genotype identification.
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Affiliation(s)
- H Gharsallah
- Department of Microbiology and research laboratory Microorganismes et Pathologie Humaine, Habib Bourguiba university hospital, Medical school of Sfax, University of Sfax, Sfax, Tunisia
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Huang CT, Li SY. Protocol for the use of a bead array for the multiple detection of genotype of Chlamydia trachomatis. Methods Mol Biol 2012; 903:195-204. [PMID: 22782819 DOI: 10.1007/978-1-61779-937-2_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The identification of Chlamydia trachomatis genotypes is important for both molecular epidemiology and infection control such as contact tracing and identification of high-risk groups. Currently, at least 19 human serovars have been recognized by using polyclonal and monoclonal antibodies against the major outer membrane protein. In sexually transmitted diseases, multiple pathogens or genotype infections are not uncommon. Hence, detection of multiple gene targets in one reaction is becoming increasingly important. Here, we describe the multiplex detection of eight genotypes of C. trachomatis by a combination of a PCR amplification with a multiplex bead array detection. The bead array system comprises distinct bead sets, which are color coded by different fluorescent intensities and a dual-laser flow cytometer analyzer to identify the identity of the bead and the intensity of the reporter dye that binds to the target molecules. The DNA sequences of the variable segments (VS2 or VS1-VS2) in outer membrane protein (omp1) gene are PCR amplified and biotin labeled and used as a gene target for the genotyping of C. trachomatis. Genotype-specific probes coupled to beads are used for capturing the labeled target amplicons through specific hybridization. Thus, multiple genotypes are detected and differentiated simultaneously by yielding quantitative data.
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Affiliation(s)
- Chung-Te Huang
- Research and Diagnostic Center, Centers for Disease Control, Taipei, Taiwan
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14
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Frigo NV, Solomka VS, Kozhushnaya OS, Rakhmatulina MR, Plakhova KI, FRIGO NV, SOLOMKA VS, KOZHUSHNAYA OS, RAKHMATULINA MR, PLAKHOVA KI. Development of the molecular typing protocol for C. Trachomatis based on the sequencing of ompa,pbpb, ct046, ct058, ct144, ct172 genes. VESTNIK DERMATOLOGII I VENEROLOGII 2011. [DOI: 10.25208/vdv1070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
The article is devoted to the development and validation of a standard operating procedure entitled «Molecular typing
of С. trachomatis for assessment of the clonal structure and extent of genetic diversity of С. trachomatis strains
circulating in the territory of the Russian Federation.» The studies that involved the typing of C. trachomatis strains
obtained from regions of the Russian Federation with the use of six c. trachomatis genes (ompA, СТ046, cT058, cT144,
cT172 and pbpB) revealed their significant heterogenicity with the prevalence of the E serotype. However, the typing of
c. trachomatis for six genes at one time seems to be too time-consuming and long-lasting and is hard to be interpreted,
which explains the need to develop other typing protocols using a smaller number of relevant genes (not more than two
or three - by analogy with NG-MAST).
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15
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Kese D, Potocnik M, Maticic M, Kogoj R. Genotyping of Chlamydia trachomatis directly from urogenital and conjunctiva samples using an ompA gene pyrosequencing-based assay. ACTA ACUST UNITED AC 2011; 63:210-6. [DOI: 10.1111/j.1574-695x.2011.00843.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Darja Kese
- Institute of Microbiology and Immunology; Medical Faculty Ljubljana; University of Ljubljana; Ljubljana; Slovenia
| | - Marko Potocnik
- Department of Dermatovenereology; University Medical Centre Ljubljana; Ljubljana; Slovenia
| | - Mojca Maticic
- Department of Infectious Diseases and Febrile Illnesses; University Medical Centre Ljubljana; Ljubljana; Slovenia
| | - Rok Kogoj
- Institute of Microbiology and Immunology; Medical Faculty Ljubljana; University of Ljubljana; Ljubljana; Slovenia
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Quint KD, Geraets DT, van den Munckhof HAM, de Koning MNC, Smelov V, Melchers WJG, de Vries HJC, Morré SA, Meijer CJM, van Alewijk DCJG, van Doorn LJ, Quint WGV. Evaluation of a novel Chlamydia trachomatis microsphere suspension assay for detection and genotyping of the different serovars in clinical samples. J Mol Diagn 2011; 13:152-9. [PMID: 21354049 DOI: 10.1016/j.jmoldx.2010.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 11/06/2010] [Accepted: 11/09/2010] [Indexed: 12/18/2022] Open
Abstract
A novel Chlamydia trachomatis (Ct) microsphere suspension (MS) assay was evaluated for identification of the different serovars, using the same PCR primer set established for the Ct Detection and genoTyping assay. Both assays can detect and identify all 14 major serovars (A, B/Ba, C, D/Da, E, F, G/Ga, H, I/Ia, J, K, L1, L2/L2a, and L3) and one genovariant of serovar J. The probe specificity for the Ct-MS assay was determined using 14 Ct reference strains and 1 clinical isolate from a genovariant of serovar J. Also, the Ct-MS assay and the Ct detection and genoTyping assay were compared in 712 Ct-positive clinical samples. The Ct-MS assay showed a highly specific reaction for all probes with the amplicons of the reference strains, giving a very low background median fluorescence intensity signal (median fluorescence intensity ≤ 10). An excellent overall agreement in the Ct detection (kappa = 0.947, 95% confidence interval, 0.89 to 0.999; McNemar's test, P = 1.000) and the Ct genotyping (kappa = 0.993, 95% confidence interval, 0.977 to 1.000; McNemar's test, P = 0.053) was observed between the Ct detection and genoTyping (DT) assay and the Ct-MS assay. In conclusion, the novel Ct-MS assay permits simultaneous detection and genotyping of Ct serovars, making the Ct-MS assay an excellent high throughput method.
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Affiliation(s)
- Koen D Quint
- DDL Diagnostic Laboratory, Voorburg, The Netherlands.
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17
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Molecular Detection of
Chlamydia trachomatis
and
Neisseria gonorrhoeae. Mol Microbiol 2011. [DOI: 10.1128/9781555816834.ch24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Novel multiplex real-time PCR system using the SNP technology for the simultaneous diagnosis of Chlamydia trachomatis, Ureaplasma parvum and Ureaplasma urealyticum and genetic typing of serovars of C. trachomatis and U. parvum in NGU. Mol Cell Probes 2010; 25:55-9. [PMID: 21167277 DOI: 10.1016/j.mcp.2010.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 12/07/2010] [Accepted: 12/07/2010] [Indexed: 11/23/2022]
Abstract
To explore the possibilities of a novel multiplex real-time PCR system for rapid diagnosis, genetic typing of serovars and clinical application in NGU, we developed a multiplex real-time PCR system for the simultaneous diagnosis of Chlamydia trachomatis, Ureaplasma parvum and Ureaplasma urealyticum and molecular detection of serovars of C. trachomatis and U. parvum in NGU using the SNP technology and TaqMan-LNA probe. In 57 pathogen-positive clinical specimens, we identified the following C. trachomatis serovars: D (20.05%, 12/57), E (36.84%, 21/57), F (19.30%, 11/57), G (8.77%, 5/57), H (5.26%, 3/57), J (3.51%, 2/57), and K (5.26%, 3/57). In 115 pathogen-positive clinical specimens, we identified the following U. parvum serovars: 1 (0.87%, 2/115), 3 (55.65%, 64/115), 6 (20.87%, 24/115) and 14 (21.74%, 25/115). Our fast pathogen diagnosis and serotyping assay using real-time TaqMan-LNA PCR may improve our ability to study the pathogenesis and epidemiology of NGU.
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Li JH, Yin YP, Zheng HP, Zhong MY, Peng RR, Wang B, Chen XS. A high-resolution melting analysis for genotyping urogenital Chlamydia trachomatis. Diagn Microbiol Infect Dis 2010; 68:366-74. [DOI: 10.1016/j.diagmicrobio.2010.07.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 07/16/2010] [Accepted: 07/21/2010] [Indexed: 11/26/2022]
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20
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SIDORENKO SV, SOLOMKA VS, KOZhUShNAYa OS, FRIGO NV, Sidorenko SV, Solomka VS, Kozhushnaya OS, Frigo NV. Methods for typing std pathogens (N. Gonorrhoeae, C. Trachomatis, T. Pallidum). VESTNIK DERMATOLOGII I VENEROLOGII 2010. [DOI: 10.25208/vdv781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Phenotypic methods were initially used for bacterial typing yet they have a number of drawbacks limiting their use. Methods of molecular and genetic typing have become wide-spread today. Among these methods, bacterial typing based on multilocus sequence
typing (Multilocus Sequence Typing - MLST) has been developing at the fastest rate. However, schemes of molecular
and genetic typing of STD pathogens as compared to other bacteria are insufficiently developed, which considerably complicates
the planning of measures aimed at the reduction of their spread.
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Development and evaluation of an ompA quantitative real-time PCR assay for Chlamydia trachomatis serovar determination. J Clin Microbiol 2010; 48:2060-5. [PMID: 20392903 DOI: 10.1128/jcm.02308-09] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Knowledge of circulating Chlamydia trachomatis serovars can be beneficial for sexual network surveillance, monitoring treatment success, and associating specific clinical manifestations. Typically, C. trachomatis serovars are predicted by nucleotide sequencing of four variable domains within the ompA gene. However, sequencing procedures can be labor-intensive, are not readily available, and can lack the capacity to identify multiple serovars. This study describes the development and evaluation of a quantitative real-time PCR (qPCR) test algorithm for the rapid prediction of C. trachomatis serovars, including ocular (A to C) and anogenital (D to L3) strains. This test comprises a primary qPCR to confirm C. trachomatis positivity and the phylogenetic group(s) present and a secondary set of qPCRs to determine specific serovars. Cell culture isolates from 15 prototypic C. trachomatis serovars were correctly identified using this assay, with no cross-reactivity observed among serovars or with other common pathogenic microorganisms. Five hundred clinical specimens (previously diagnosed as being C. trachomatis positive) were evaluated by qPCR, with their results compared to results obtained by conventional sequencing. The qPCR identified 88.9% (423/476) complete matches (95% confidence interval [CI], 86 to 92%) of serovars compared to the results obtained using the sequence-based approach. Among the anogenital specimens, 2.4% (12/494) (95% CI, 1.3 to 4.2%) contained multiple serovars, categorized as single-serovar infections by conventional sequencing. Overall, this test exhibited high discriminatory success for predicting C. trachomatis serovars, particularly among anogenital infections. This is the first report of a qPCR typing assay offering differentiation of C. trachomatis serovars associated with both anogenital and ocular diseases.
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Pedersen LN, Herrmann B, Møller JK. Typing Chlamydia trachomatis: from egg yolk to nanotechnology. ACTA ACUST UNITED AC 2009; 55:120-30. [PMID: 19281564 DOI: 10.1111/j.1574-695x.2008.00526.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A historical review is provided of the various methods used for half a century to differentiate and type Chlamydia trachomatis strains. Typing of C. trachomatis is an important tool for revealing transmission patterns in sexual networks, and enabling association with clinical manifestations and pathogenicity. Serotyping using the major outer membrane protein (MOMP) has been the mainstay of epidemiological work for several decades. However, the development of nucleic acid amplification techniques (NAAT) and easy access to sequencing have shifted the focus from MOMP serotypes to omp1 genotypes. However, insufficient epidemiological resolution is achieved by characterization of both MOMP and omp1. This calls for new high-resolution genotyping methods applying for example a multilocus variable number tandem repeat assay (MLVA) or multilocus sequence typing (MLST). The futuristic nanotechnology already seems at hand to further simplify and automate the high-resolution genotyping method based on NAAT and sequencing of various targets in the C. trachomatis genome. Thereby, a high throughput can be achieved and more epidemiological information can be obtained. However, it is important to realize that culture of C. trachomatis may still be needed to detect and characterize new variants of C. trachomatis.
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Schaeffer A, Henrich B. Rapid detection of Chlamydia trachomatis and typing of the Lymphogranuloma venereum associated L-Serovars by TaqMan PCR. BMC Infect Dis 2008; 8:56. [PMID: 18447917 PMCID: PMC2387162 DOI: 10.1186/1471-2334-8-56] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Accepted: 04/30/2008] [Indexed: 11/10/2022] Open
Abstract
Background Infection due to Chlamydia trachomatis is the most common sexually transmitted bacterial disease of global health significance, and especially the L-serovars causing lymphogranuloma venereum are increasingly being found in Europe in men who have sex with men. Results The design and evaluation of a rapid, multiplex, real-time PCR targeting the major outer membrane protein (omp-1) -gene and a L-serovar-specific region of the polymorphic protein H (pmp-H) -gene for the detection of Chlamydia trachomatis is reported here. The PCR takes place as a single reaction with an internal control. For L1-, L2- and L3-serovar differentiation a second set of real-time PCRs was evaluated based on the amplification of serovar-specific omp-1-regions. The detection limit of each real-time PCR, multiplexed or not, was 50 genome copies per reaction with an efficiency ranging from 90,5–95,2%. In a retrospective analysis of 50 ocular, rectal and urogenital specimens formerly tested to be positive for C. trachomatis we identified six L2-serovars in rectal specimens of HIV-positive men, one in a double-infection with L3, and one L2 in a urethral specimen of an HIV-negative male. Conclusion This unique real-time PCR is specific and convenient for the rapid routine-diagnostic detection of lymphogranuloma venereum-associated L-serovars and enables the subsequent differentiation of L1, L2 and L3 for epidemiologic studies.
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Affiliation(s)
- Anke Schaeffer
- Institute of Medical Microbiology and Hospital Hygiene, Clinical Center of Heinrich-Heine University, Moorenstrasse 5, 40225 Duesseldorf, Germany.
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Abstract
The identification of Chlamydia trachomatis genotypes is important for both the study of molecular epidemiology and infection control. We have developed a microsphere suspension array assay that can identify C. trachomatis genotypes rapidly and accurately and also discriminate among multiple genotypes in one clinical specimen.
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25
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Jalal H, Stephen H, Alexander S, Carne C, Sonnex C. Development of real-time PCR assays for genotyping of Chlamydia trachomatis. J Clin Microbiol 2007; 45:2649-53. [PMID: 17567790 PMCID: PMC1951269 DOI: 10.1128/jcm.00451-07] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We have developed and validated a nested real-time PCR (NRT-PCR) for the genotyping of Chlamydia trachomatis and used it specifically for the typing of either eight genovars from D to K or three genovars of lymphogranuloma venereum (LGV). The 11 probes used in the NRT-PCR correctly identified the DNA from D to K and LGV reference strains and did not cross-react with the DNA from 26 strains representing the bacterial pathogens and commensals of the oropharynx, genital tract, and rectum. The NRT-PCR had a 95% probability of detection at four genome copies (confidence interval, three to six copies) of C. trachomatis per reaction. One hundred cervical and urethral swab specimens containing C. trachomatis DNA from 63 women and 37 men were used to validate the method. The results from the NRT-PCR and the DNA sequencing of amplicons generated from the omp1 gene showed 100% correlation for these samples. The assay also identified the LGV-II genotype in 24 of 48 rectal swab specimens containing C. trachomatis DNA that were obtained from men having sex with men. The Sexually Transmitted Bacteria Reference Laboratory, London, independently confirmed these results using group-specific LGV real-time PCR and restriction fragment length polymorphism analysis. Compared with the NRT-PCR, non-NRT-PCR was found to be less sensitive: it typed C. trachomatis DNA in only 80% of the genital samples and 90% of the rectal swab samples. This is the first successful demonstration of the use of real-time PCR for the genotype-specific typing of C. trachomatis strains that cause sexually transmitted diseases.
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Affiliation(s)
- Hamid Jalal
- Clinical Microbiology & Public Health Laboratory, Box 236, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QW, United Kingdom.
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