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Development and Validation of a Sensitive and Robust Multiplex Antigen Capture Assay to Quantify Streptococcus pneumoniae Serotype-Specific Capsular Polysaccharides in Urine. mSphere 2022; 7:e0011422. [PMID: 35913133 PMCID: PMC9429912 DOI: 10.1128/msphere.00114-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Streptococcus pneumoniae is a major cause of community-acquired pneumonia (CAP) in young children, older adults, and those with immunocompromised status. Since the introduction of pneumococcal vaccines, the burden of invasive pneumococcal disease caused by vaccine serotypes (STs) has decreased; however, the effect on the burden of CAP is unclear, potentially due to the lack of testing for pneumococcal STs. We describe the development, qualification, and clinical validation of a high-throughput and multiplex ST-specific urine antigen detection (SSUAD) assay to address the unmet need in CAP pneumococcal epidemiology. The SSUAD assay is sensitive and specific to the 15 STs in the licensed pneumococcal conjugate vaccine V114 (STs 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F, and 33F) and uses ST-specific monoclonal antibodies for rapid and simultaneous quantification of the 15 STs using a Luminex microfluidics system. The SSUAD assay was optimized and qualified using healthy adult urine spiked with pneumococcal polysaccharides and validated using culture-positive clinical urine samples (n = 34). Key parameters measured were accuracy, precision, sensitivity, specificity, selectivity, and parallelism. The SSUAD assay met all prespecified validation acceptance criteria and is suitable for assessments of disease burden associated with the 15 pneumococcal STs included in V114. IMPORTANCEStreptococcus pneumoniae has more than 90 serotypes capable of causing a range of disease manifestations, including otitis media, pneumonia, and invasive diseases, such as bacteremia or meningitis. Only a minority (<10%) of pneumococcal diseases are bacteremic with known serotype distribution. Culture and serotyping of respiratory specimens are neither routine nor reliable. Hence, the serotype-specific disease burden of the remaining (>90%) noninvasive conditions is largely unknown without reliable laboratory techniques. To address this need, a 15-plex urine antigen detection assay was developed and validated to quantify pneumococcal serotype-specific capsular polysaccharides in urine. This assay will support surveillance to estimate the pneumococcal disease burden and serotype distribution in nonbacteremic conditions. Data obtained from this assay will be critical for understanding the impact of pneumococcal vaccines on noninvasive pneumococcal diseases and to inform the choice of pneumococcal serotypes for next-generation vaccines.
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Development of an Extended-Specificity Multiplex Immunoassay for Detection of Streptococcus pneumoniae Serotype-Specific Antigen in Urine by Use of Human Monoclonal Antibodies. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00262-17. [PMID: 28978509 DOI: 10.1128/cvi.00262-17] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 09/30/2017] [Indexed: 11/20/2022]
Abstract
Current pneumococcal vaccines cover the 10 to 23 most common serotypes of the 92 presently described. However, with the increased usage of pneumococcal-serotype-based vaccines, the risk of serotype replacement and an increase in disease caused by nonvaccine serotypes remains. Serotype surveillance of pneumococcal infections relies heavily on culture techniques, which are known to be insensitive, particularly in cases of noninvasive disease. Pneumococcal-serotype-specific urine assays offer an alternative method of serotyping for both invasive and noninvasive disease. However, the assays described previously cover mainly conjugate vaccine serotypes, give little information about circulating nonvaccine serotypes, and are currently available only in one or two specialist laboratories. Our laboratory has developed a Luminex-based extended-range antigen capture assay to detect pneumococcal-serotype-specific antigens in urine samples. The assay targets 24 distinct serotypes/serogroups plus the cell wall polysaccharide (CWP) and some cross-reactive serotypes. We report that the assay is capable of detecting all the targeted serotypes and the CWP at 0.1 ng/ml, while some serotypes are detected at concentrations as low as 0.3 pg/ml. The analytical serotype specificity was determined to be 98.4% using a panel of polysaccharide-negative urine specimens spiked with nonpneumococcal bacterial antigens. We also report clinical sensitivities of 96.2% and specificities of 89.9% established using a panel of urine specimens from patients diagnosed with community-acquired pneumonia or pneumococcal disease. This assay can be extended for testing other clinical samples and has the potential to greatly improve serotype-specific surveillance in the many cases of pneumococcal disease in which a culture is never obtained.
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Satzke C, Dunne EM, Porter BD, Klugman KP, Mulholland EK. The PneuCarriage Project: A Multi-Centre Comparative Study to Identify the Best Serotyping Methods for Examining Pneumococcal Carriage in Vaccine Evaluation Studies. PLoS Med 2015; 12:e1001903; discussion e1001903. [PMID: 26575033 PMCID: PMC4648509 DOI: 10.1371/journal.pmed.1001903] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 10/09/2015] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The pneumococcus is a diverse pathogen whose primary niche is the nasopharynx. Over 90 different serotypes exist, and nasopharyngeal carriage of multiple serotypes is common. Understanding pneumococcal carriage is essential for evaluating the impact of pneumococcal vaccines. Traditional serotyping methods are cumbersome and insufficient for detecting multiple serotype carriage, and there are few data comparing the new methods that have been developed over the past decade. We established the PneuCarriage project, a large, international multi-centre study dedicated to the identification of the best pneumococcal serotyping methods for carriage studies. METHODS AND FINDINGS Reference sample sets were distributed to 15 research groups for blinded testing. Twenty pneumococcal serotyping methods were used to test 81 laboratory-prepared (spiked) samples. The five top-performing methods were used to test 260 nasopharyngeal (field) samples collected from children in six high-burden countries. Sensitivity and positive predictive value (PPV) were determined for the test methods and the reference method (traditional serotyping of >100 colonies from each sample). For the alternate serotyping methods, the overall sensitivity ranged from 1% to 99% (reference method 98%), and PPV from 8% to 100% (reference method 100%), when testing the spiked samples. Fifteen methods had ≥70% sensitivity to detect the dominant (major) serotype, whilst only eight methods had ≥70% sensitivity to detect minor serotypes. For the field samples, the overall sensitivity ranged from 74.2% to 95.8% (reference method 93.8%), and PPV from 82.2% to 96.4% (reference method 99.6%). The microarray had the highest sensitivity (95.8%) and high PPV (93.7%). The major limitation of this study is that not all of the available alternative serotyping methods were included. CONCLUSIONS Most methods were able to detect the dominant serotype in a sample, but many performed poorly in detecting the minor serotype populations. Microarray with a culture amplification step was the top-performing method. Results from this comprehensive evaluation will inform future vaccine evaluation and impact studies, particularly in low-income settings, where pneumococcal disease burden remains high.
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Affiliation(s)
- Catherine Satzke
- Pneumococcal Research Group, Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
- Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
- * E-mail:
| | - Eileen M. Dunne
- Pneumococcal Research Group, Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
| | - Barbara D. Porter
- Pneumococcal Research Group, Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
| | - Keith P. Klugman
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - E. Kim Mulholland
- Pneumococcal Research Group, Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Jauneikaite E, Tocheva AS, Jefferies JMC, Gladstone RA, Faust SN, Christodoulides M, Hibberd ML, Clarke SC. Current methods for capsular typing of Streptococcus pneumoniae. J Microbiol Methods 2015; 113:41-9. [PMID: 25819558 DOI: 10.1016/j.mimet.2015.03.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 02/21/2015] [Accepted: 03/08/2015] [Indexed: 10/23/2022]
Abstract
Streptococcus pneumoniae is a major respiratory tract pathogen causing pneumococcal disease mainly in children aged less than five years and in the elderly. Ninety-eight different capsular types (serotypes) of pneumococci have been reported, but pneumococcal conjugate vaccines (PCV) include polysaccharide antigens against only 7, 10 or 13 serotypes. It is therefore important to track the emergence of serotypes due to the clonal expansion of non-vaccine serotypes. Increased numbers of carried and disease-causing pneumococci are now being analysed as part of the post-PCV implementation surveillance studies and hence rapid, accurate and cost-effective typing methods are important. Here we describe serotyping methods published prior to 10th November 2014 for pneumococcal capsule typing. Sixteen methods were identified; six were based on serological tests using immunological properties of the capsular epitopes, eight were semi-automated molecular tests, and one describes the identification of capsular type directly from whole genome data, which also allows for further intra and inter-genome analyses. There was no single method that could be recommended for all pneumococcal capsular typing applications. Although the Quellung reaction is still considered to be the gold-standard, laboratories should take into account the number of pneumococcal isolates and the type of samples to be used for testing, the time frame for the results and the resources available in order to select the most appropriate method. Most likely, a combination of phenotypic and genotypic methods would be optimal to monitor and evaluate the impact of pneumococcal conjugate vaccines and to provide information for future vaccine formulations.
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Affiliation(s)
- Elita Jauneikaite
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK; Infectious Diseases, Genome Institute of Singapore, 138672, Singapore
| | - Anna S Tocheva
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK
| | - Johanna M C Jefferies
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK; NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Rebecca A Gladstone
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK
| | - Saul N Faust
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK; NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK; NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Myron Christodoulides
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK
| | - Martin L Hibberd
- Infectious Diseases, Genome Institute of Singapore, 138672, Singapore; London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Stuart C Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO16 6YD, UK; NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK.
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5
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Elberse K, van Mens S, Cremers AJ, Meijvis SCA, Vlaminckx B, de Jonge MI, Meis JF, Blauwendraat C, van de Pol I, Schouls LM. Detection and serotyping of pneumococci in community acquired pneumonia patients without culture using blood and urine samples. BMC Infect Dis 2015; 15:56. [PMID: 25885896 PMCID: PMC4330648 DOI: 10.1186/s12879-015-0788-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 01/29/2015] [Indexed: 11/23/2022] Open
Abstract
Background Treatment of community acquired pneumonia (CAP) patients with antibiotics before laboratory-confirmed diagnosis leads to loss of knowledge on the causative bacterial pathogen. Therefore, an increasing number of pneumococcal infections is identified using non-culture based techniques. However, methods for serotyping directly on the clinical specimen remain scarce. Here we present three approaches for detection and serotyping of pneumococci using samples from patients with CAP. Methods The first approach is quantitative PCR (qPCR) analysis on blood samples (n = 211) followed by capsular sequence typing (CST) to identify the serotype. The second approach, a urinary antigen assay (n = 223), designated as inhibition multiplex immunoassay (IMIA), is based on Luminex technology targeting 14 serotypes. The third approach is a multiplex immunoassay (MIA) (n = 171) also based on Luminex technology which detects serologic antibody responses against 14 serotypes. The three alternative assays were performed on samples obtained from 309 adult hospitalized CAP patients in 2007–2010 and the results were compared with those obtained from conventional laboratory methods to detect pneumococcal CAP, i.e. blood cultures, sputum cultures and BinaxNOW® urinary antigen tests. Results Using qPCR, MIA and IMIA, we were able to detect the pneumococcus in samples of 56% more patients compared to conventional methods. Furthermore, we were able to assign a serotype to the infecting pneumococcus from samples of 25% of all CAP patients, using any of the three serotyping methods (CST, IMIA and MIA). Conclusion This study indicates the usefulness of additional molecular methods to conventional laboratory methods for the detection of pneumococcal pneumonia. Direct detection and subsequent serotyping on clinical samples will improve the accuracy of pneumococcal surveillance to monitor vaccine effectiveness.
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Affiliation(s)
- Karin Elberse
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment (RIVM), Laboratory for Infectious Diseases and Perinatal Screening, Antonie van Leeuwenhoeklaan 9, P.O.Box 1, 3720 BA, Bilthoven, The Netherlands.
| | - Suzan van Mens
- Departments of Medical Microbiology & Immunology, Sint Antonius Hospital Nieuwegein, P.O box 2500, 3430 EM, Nieuwegein, The Netherlands.
| | - Amelieke J Cremers
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6525 GA, Nijmegen, The Netherlands. .,Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6525 GA, Nijmegen, The Netherlands.
| | - Sabine C A Meijvis
- Department of Internal medicine, Sint Antonius Hospital Nieuwegein, P.O box 2500, 3430 EM, Nieuwegein, The Netherlands.
| | - Bart Vlaminckx
- Departments of Medical Microbiology & Immunology, Sint Antonius Hospital Nieuwegein, P.O box 2500, 3430 EM, Nieuwegein, The Netherlands.
| | - Marien I de Jonge
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6525 GA, Nijmegen, The Netherlands. .,Laboratory of Medical Immunology, Department of Laboratory Medicine, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6525 GA, Nijmegen, The Netherlands.
| | - Jacques F Meis
- Department of Medical Microbiology, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6525 GA, Nijmegen, The Netherlands. .,Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Hospital, Weg door Jonkerbos 100, 6532 SZ, Nijmegen, The Netherlands.
| | - Cornelis Blauwendraat
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment (RIVM), Laboratory for Infectious Diseases and Perinatal Screening, Antonie van Leeuwenhoeklaan 9, P.O.Box 1, 3720 BA, Bilthoven, The Netherlands.
| | - Ingrid van de Pol
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment (RIVM), Laboratory for Infectious Diseases and Perinatal Screening, Antonie van Leeuwenhoeklaan 9, P.O.Box 1, 3720 BA, Bilthoven, The Netherlands.
| | - Leo M Schouls
- Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment (RIVM), Laboratory for Infectious Diseases and Perinatal Screening, Antonie van Leeuwenhoeklaan 9, P.O.Box 1, 3720 BA, Bilthoven, The Netherlands.
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Satzke C, Turner P, Virolainen-Julkunen A, Adrian PV, Antonio M, Hare KM, Henao-Restrepo AM, Leach AJ, Klugman KP, Porter BD, Sá-Leão R, Scott JA, Nohynek H, O'Brien KL. Standard method for detecting upper respiratory carriage of Streptococcus pneumoniae: updated recommendations from the World Health Organization Pneumococcal Carriage Working Group. Vaccine 2014; 32:165-79. [PMID: 24331112 DOI: 10.1016/j.vaccine.2013.08.062] [Citation(s) in RCA: 328] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 07/25/2013] [Accepted: 08/23/2013] [Indexed: 11/29/2022]
Abstract
In 2003 the World Health Organization (WHO) convened a working group and published a set of standard methods for studies measuring nasopharyngeal carriage of Streptococcus pneumoniae (the pneumococcus). The working group recently reconvened under the auspices of the WHO and updated the consensus standard methods. These methods describe the collection, transport and storage of nasopharyngeal samples, as well as provide recommendations for the identification and serotyping of pneumococci using culture and non-culture based approaches. We outline the consensus position of the working group, the evidence supporting this position, areas worthy of future research, and the epidemiological role of carriage studies. Adherence to these methods will reduce variability in the conduct of pneumococcal carriage studies undertaken in the context of pneumococcal vaccine trials, implementation studies, and epidemiology studies more generally so variability in methodology does not confound the interpretation of study findings.
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Affiliation(s)
- Catherine Satzke
- Pneumococcal Research, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, VIC, Australia; Centre for International Child Health, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, VIC, Australia; Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC, Australia.
| | - Paul Turner
- Microbiology Department, Angkor Hospital for Children, Siem Reap, Kingdom of Cambodia; Centre for Tropical Medicine, University of Oxford, Oxford, United Kingdom
| | - Anni Virolainen-Julkunen
- Department of Infectious Disease Surveillance and Control, National Institute for Health and Welfare, Helsinki, Finland
| | - Peter V Adrian
- MRC/Wits Respiratory and Meningeal Pathogens Research Unit, University of the Witwatersrand, Johannesburg, South Africa
| | | | - Kim M Hare
- Child Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | | | - Amanda J Leach
- Child Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Keith P Klugman
- Rollins School of Public Health, Emory University, Atlanta, GA, USA; Respiratory and Meningeal Pathogens Research Unit, University of Witwatersrand, Johannesburg, South Africa
| | - Barbara D Porter
- Pneumococcal Research, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, VIC, Australia
| | - Raquel Sá-Leão
- Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - J Anthony Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; London School of Hygiene & Tropical Medicine, London, UK
| | - Hanna Nohynek
- Vaccine Programme Unit, National Institute for Health and Welfare, Helsinki, Finland
| | - Katherine L O'Brien
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Pride MW, Huijts SM, Wu K, Souza V, Passador S, Tinder C, Song E, Elfassy A, McNeil L, Menton R, French R, Callahan J, Webber C, Gruber WC, Bonten MJM, Jansen KU. Validation of an immunodiagnostic assay for detection of 13 Streptococcus pneumoniae serotype-specific polysaccharides in human urine. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1131-41. [PMID: 22675155 PMCID: PMC3416073 DOI: 10.1128/cvi.00064-12] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 05/25/2012] [Indexed: 11/20/2022]
Abstract
To improve the clinical diagnosis of pneumococcal infection in bacteremic and nonbacteremic community-acquired pneumonia (CAP), a Luminex technology-based multiplex urinary antigen detection (UAD) diagnostic assay was developed and validated. The UAD assay can simultaneously detect 13 different serotypes of Streptococcus pneumoniae by capturing serotype-specific S. pneumoniae polysaccharides (PnPSs) secreted in human urine. Assay specificity is achieved by capturing the polysaccharides with serotype-specific monoclonal antibodies (MAbs) on spectrally unique microspheres. Positivity for each serotype was based on positivity cutoff values calculated from a standard curve run on each assay plate together with positive- and negative-control urine samples. The assay is highly specific, since significant signals are detected only when each PnPS was paired with its homologous MAb-coated microspheres. Validation experiments demonstrated excellent accuracy and precision. The UAD assay and corresponding positivity cutoff values were clinically validated by assessing 776 urine specimens obtained from patients with X-ray-confirmed CAP. The UAD assay demonstrated 97% sensitivity and 100% specificity using samples obtained from patients with bacteremic, blood culture-positive CAP. Importantly, the UAD assay identified Streptococcus pneumoniae (13 serotypes) in a proportion of individuals with nonbacteremic CAP, a patient population for which the pneumococcal etiology of CAP was previously difficult to assess. Therefore, the UAD assay provides a specific, noninvasive, sensitive, and reproducible tool to support vaccine efficacy as well as epidemiological evaluation of pneumococcal disease, including CAP, in adults.
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Affiliation(s)
- Michael W Pride
- Vaccine Research East and Early Development, Pfizer Research, Pearl River, New York, New York, USA.
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8
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Sacchi CT, Fukasawa LO, Gonçalves MG, Salgado MM, Shutt KA, Carvalhanas TR, Ribeiro AF, Kemp B, Gorla MCO, Albernaz RK, Marques EGL, Cruciano A, Waldman EA, Brandileone MCC, Harrison LH. Incorporation of real-time PCR into routine public health surveillance of culture negative bacterial meningitis in São Paulo, Brazil. PLoS One 2011; 6:e20675. [PMID: 21731621 PMCID: PMC3120771 DOI: 10.1371/journal.pone.0020675] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 05/09/2011] [Indexed: 01/03/2023] Open
Abstract
Real-time (RT)-PCR increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. We validated a multiplex RT-PCR assay for Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae in Brazil. Risk factors for being culture-negative, RT-PCR positive were determined. The sensitivity of RT-PCR in cerebrospinal fluid (CSF) was 100% (95% confidence limits, 96.0%-100%) for N. meningitidis, 97.8% (85.5%-99.9%) for S. pneumoniae, and 66.7% (9.4%-99.2%) for H. influenzae. Specificity ranged from 98.9% to 100%. Addition of RT-PCR to routine microbiologic methods increased the yield for detection of S. pneumoniae, N. meningitidis, and H. influenzae cases by 52%, 85%, and 20%, respectively. The main risk factor for being culture negative and RT-PCR positive was presence of antibiotic in CSF (odds ratio 12.2, 95% CI 5.9-25.0). RT-PCR using CSF was highly sensitive and specific and substantially added to measures of meningitis disease burden when incorporated into routine public health surveillance in Brazil.
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Affiliation(s)
- Claudio T Sacchi
- Division of Medical Biology, Department of Immunology, Instituto Adolfo Lutz, São Paulo, Brazil.
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9
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Carrol ED, Mankhambo LA, Guiver M, Banda DL, Denis B, Dove W, Jeffers G, Molyneux EM, Molyneux ME, Hart CA, Graham SM. PCR improves diagnostic yield from lung aspiration in Malawian children with radiologically confirmed pneumonia. PLoS One 2011; 6:e21042. [PMID: 21695128 PMCID: PMC3114850 DOI: 10.1371/journal.pone.0021042] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 05/17/2011] [Indexed: 11/28/2022] Open
Abstract
Background Accurate data on childhood pneumonia aetiology are essential especially from regions where mortality is high, in order to inform case-management guidelines and the potential of prevention strategies such as bacterial conjugate vaccines. Yield from blood culture is low, but lung aspirate culture provides a higher diagnostic yield. We aimed to determine if diagnostic yield could be increased further by polymerase chain reaction (PCR) detection of bacteria (Streptococcus pneumoniae and Haemophilus influenzae b) and viruses in lung aspirate fluid. Methods A total of 95 children with radiological focal, lobar or segmental consolidation had lung aspirate performed and sent for bacterial culture and for PCR for detection of bacteria, viruses and Pneumocystis jirovecii. In children with a pneumococcal aetiology, pneumococcal bacterial loads were calculated in blood and lung aspirate fluid. Results Blood culture identified a bacterial pathogen in only 8 patients (8%). With the addition of PCR on lung aspirate samples, causative pathogens (bacterial, viral, pneumocystis) were identified singly or as co-infections in 59 children (62%). The commonest bacterial organism was S.pneumoniae (41%), followed by H. influenzae b (6%), and the commonest virus identified was adenovirus (16%), followed by human bocavirus (HBoV) (4%), either as single or co-infection. Conclusions In a select group of African children, lung aspirate PCR significantly improves diagnostic yield. Our study confirms a major role of S.pneumoniae and viruses in the aetiology of childhood pneumonia in Africa.
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Affiliation(s)
- Enitan D Carrol
- Department of Women's and Children's Health, The University of Liverpool, Institute of Child Health, Alder Hey Children's NHS Foundation Trust, Liverpool, United Kingdom.
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Vernet G, Saha S, Satzke C, Burgess D, Alderson M, Maisonneuve JF, Beall B, Steinhoff M, Klugman K. Laboratory-based diagnosis of pneumococcal pneumonia: state of the art and unmet needs. Clin Microbiol Infect 2011; 17 Suppl 3:1-13. [DOI: 10.1111/j.1469-0691.2011.03496.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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11
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Optimization and application of a multiplex bead-based assay to quantify serotype-specific IgG against Streptococcus pneumoniae polysaccharides: response to the booster vaccine after immunization with the pneumococcal 7-valent conjugate vaccine. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 17:674-82. [PMID: 20130129 DOI: 10.1128/cvi.00408-09] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We describe the optimization and application of a multiplex bead-based assay (Luminex) to quantify antibodies against polysaccharides of 13 pneumococcal serotypes. In the optimized multiplex immunoassay (MIA), intravenous immune globulin was introduced as an in-house reference serum, and nonspecific reacting antibodies were adsorbed with the commercial product pneumococcal C polysaccharides Multi. The antibody concentrations were assessed in 188 serum samples obtained pre- and post-booster vaccination at 11 months after administration of a primary series of the pneumococcal seven-valent conjugate vaccine (PCV-7) at 2, 3, and 4 months of age. The results of the MIA were compared with those of the ELISA for the serotypes included in the seven-valent conjugated polysaccharide vaccine and for a non-vaccine serotype, serotype 6A. The geometric mean concentrations of the antibodies determined by MIA were slightly higher than those determined by ELISA. The correlations between the assays were good, with R(2) values ranging from 0.84 to 0.91 for all serotypes except serotype 19F, for which R(2) was 0.70. The concentrations of antibody against serotype 6A increased after the administration of PCV-7 due to cross-reactivity with serotype 6B. The differences between the results obtained by ELISA and MIA suggest that the internationally established protective threshold of 0.35 microg/ml should be reevaluated for use in the MIA and may need to be amended separately for each serotype.
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12
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Pneumococcal serotypes causing pediatric meningitis in Turkey: application of a new technology in the investigation of cases negative by conventional culture. Eur J Clin Microbiol Infect Dis 2010; 29:289-93. [PMID: 20087750 DOI: 10.1007/s10096-009-0853-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 12/05/2009] [Indexed: 10/20/2022]
Abstract
The surveillance of serotypes causing invasive pneumococcal disease (IPD) provides further insight into the pathogenesis of pneumococcal disease and is important in order to track vaccine impact. Although the Quellung reaction has been accepted as the standard method for serotyping, prior antibiotic use causes a gap in studies based on bacterial culture. A total of 31 cerebrospinal fluid (CSF) samples found to be positive for Streptococcus pneumoniae by polymerase chain reaction (PCR) targeting the ply gene during an active surveillance were tested in a Bio-Plex multiplex antigen detection assay capable of detecting 14 serotypes/groups (1, 3, 4, 5, 6A, 6B, 7F/A, 8, 9V, 14, 18, 19A, 19F, and 23F). Twenty-seven CSF samples could be serotyped. The most common serotypes were serotypes 5 (n = 7), 19F (n = 5), 1 (n = 3), and 23F (n = 3). Theoretical coverage rates by the heptavalent (PCV7), 10-valent (PCV10), and 13-valent (PCV13) pneumococcal conjugate vaccines for bacterial meningitis were 48.1, 85.2, and 92.3%, respectively, for all age groups and 71.4, 85.7, and 100.0%, respectively, for those under 2 years of age. We propose that antigen detection assay used in conjunction with a PCR assay can be effectively applied in CSF samples to detect the pneumococcal serotypes, especially when the patient may have already been treated and, therefore, the cultures would be negative.
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