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Jiang T, Hu X, Shen J. Establishment of a Novel Detection Platform for Clostridioides difficile Toxin Genes Based on Orthogonal CRISPR. Microbiol Spectr 2023; 11:e0188623. [PMID: 37378559 PMCID: PMC10434169 DOI: 10.1128/spectrum.01886-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
Clostridioides difficile is one of the leading pathogens causing nosocomial infection. The infection can range from mild to severe, and rapid identification is pivotal for early clinical diagnosis and appropriate treatment. Here, a genetic testing platform for toxins, referred to as OC-MAB (orthogonal CRISPR system combined with multiple recombinase polymerase amplification [RPA]), was developed to detect the C. difficile toxin genes tcdA and tcdB. While recognizing the amplified products of the tcdA gene and the tcdB gene, Cas13a and Cas12a could activate their cleavage activities to cut labeled RNA and DNA probes, respectively. The cleaved products were subsequently identified by dual-channel fluorescence using a quantitative PCR (qPCR) instrument. Finally, they could also be combined with labeled antibodies on immunochromatographic test strips to achieve visual detection. The OC-MAB platform exhibited ultrahigh sensitivity in detecting the tcdA and tcdB genes at levels of as low as 102 to 101 copies/mL. When testing 72 clinical stool samples, the sensitivity (95% confidence interval [CI], 0.90, 1) and specificity (95% CI, 0.84, 1) of the single-tube method based on the fluorescence readout was 100%, with a positive predictive value (PPA) value of 100% (95% CI, 0.90, 1) and a negative predictive value (NPA) value of 100% (95% CI, 0.84, 1), compared to the results of qPCR. Likewise, the sensitivity of the 2-step method based on the test strip readout was 100% (95% CI, 0.90, 1), while the specificity was 96.3% (95% CI, 0.79, 0.99), with a PPA of 98% (95% CI, 0.87, 0.99) and an NPA of 100% (95% CI, 0.90, 1). In short, orthogonal CRISPR technology is a promising tool for the detection of C. difficile toxin genes. IMPORTANCE C. difficile is currently the primary causative agent of hospital-acquired antibiotic-induced diarrhea, and timely and accurate diagnosis is crucial for hospital-acquired infection control and epidemiological investigation. Here, a new method for the identification of C. difficile was developed based on the recently popular CRISPR technology, and an orthogonal CRISPR dual system was utilized for the simultaneous detection of toxin genes A and B. It also uses a currently rare CRISPR dual-target lateral flow strip with powerful color-changing capabilities, which is appropriate for point-of-care testing (POCT).
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Affiliation(s)
- Tong Jiang
- The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Xinyi Hu
- The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Jilu Shen
- The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
- Anhui Public Health Clinical Center, Hefei, Anhui, China
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Raeisi H, Azimirad M, Asadzadeh Aghdaei H, Yadegar A, Zali MR. Rapid-format recombinant antibody-based methods for the diagnosis of Clostridioides difficile infection: Recent advances and perspectives. Front Microbiol 2022; 13:1043214. [PMID: 36523835 PMCID: PMC9744969 DOI: 10.3389/fmicb.2022.1043214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 10/13/2022] [Indexed: 08/30/2023] Open
Abstract
Clostridioides difficile, the most common cause of nosocomial diarrhea, has been continuously reported as a worldwide problem in healthcare settings. Additionally, the emergence of hypervirulent strains of C. difficile has always been a critical concern and led to continuous efforts to develop more accurate diagnostic methods for detection of this recalcitrant pathogen. Currently, the diagnosis of C. difficile infection (CDI) is based on clinical manifestations and laboratory tests for detecting the bacterium and/or its toxins, which exhibit varied sensitivity and specificity. In this regard, development of rapid diagnostic techniques based on antibodies has demonstrated promising results in both research and clinical environments. Recently, application of recombinant antibody (rAb) technologies like phage display has provided a faster and more cost-effective approach for antibody production. The application of rAbs for developing ultrasensitive diagnostic tools ranging from immunoassays to immunosensors, has allowed the researchers to introduce new platforms with high sensitivity and specificity. Additionally, DNA encoding antibodies are directly accessible in these approaches, which enables the application of antibody engineering to increase their sensitivity and specificity. Here, we review the latest studies about the antibody-based ultrasensitive diagnostic platforms for detection of C. difficile bacteria, with an emphasis on rAb technologies.
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Affiliation(s)
- Hamideh Raeisi
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoumeh Azimirad
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hamid Asadzadeh Aghdaei
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Yadegar
- Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Zali
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Ojha SC, Chen K, Sun C, Ahmed S, Sheng YJ, Deng CL. Clinical Relevance of Xpert MRSA/SA in Guiding Therapeutic Decisions for Staphylococcal Infections: A Diagnostic Test Accuracy Analysis. Infect Dis Ther 2022; 11:1205-1227. [PMID: 35451743 PMCID: PMC9124268 DOI: 10.1007/s40121-022-00632-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 03/30/2022] [Indexed: 11/12/2022] Open
Abstract
Introduction Rapid identification of the causal organism and antibiotic resistance is crucial for guiding targeted therapy in patients with suspected staphylococcal infection. A meta-analysis was carried out to evaluate the diagnostic relevance of Xpert™ MRSA/SA (Xpert) from clinical samples of various origins for limiting the use of unnecessary empirical methicillin-resistant Staphylococcus aureus (MRSA) therapy. Methods Five databases, including the Cochrane Library, Scopus, PubMed, Web of Science, and Embase, were comprehensively inspected from inception to October 12, 2021. The pooled summary estimates were evaluated using a bivariate random-effects model. Results Our inclusion criteria were met by 49 publications containing 68 datasets out of 735 citations. A total of 21 studies (n = 4996) examined the accuracy of Xpert in detecting methicillin-sensitive S. aureus (MSSA), while 47 studies (n = 45,430) examined the accuracy of Xpert in detecting MRSA. As compared to MRSA, Xpert’s diagnostic performance for MSSA detection was markedly higher [sensitivity: 0.97 (0.96–0.98), specificity: 0.97 (0.97–0.98), area under curve (AUC): 0.99 (0.99–1.0)]. Xpert’s pooled sensitivity and specificity differed marginally across sample types, including screening of colonization, lower respiratory tract (LRT), osteoarticular, and bloodstream samples. Notably, the Xpert pooled specificity was consistently ≥ 92% against microbiological culture across all sample types. The diagnostic efficiency heterogeneity was not explained by a meta-regression and subgroup analysis of research design, sample conditions, and sampling methods (P > 0.05). Conclusion Our findings suggest that Xpert could be used as the favoured screening test for the early detection of staphylococcal infection in a variety of sample types, with the goal of guiding therapeutic decisions. Supplementary Information The online version contains supplementary material available at 10.1007/s40121-022-00632-w.
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Affiliation(s)
- Suvash Chandra Ojha
- Department of Infectious Diseases, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China. .,Southwest Medical University, Jiangyang District, Luzhou, 646000, China.
| | - Ke Chen
- Department of Infectious Diseases, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China.,Southwest Medical University, Jiangyang District, Luzhou, 646000, China
| | - Changfeng Sun
- Department of Infectious Diseases, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China.,Southwest Medical University, Jiangyang District, Luzhou, 646000, China
| | - Sarfraz Ahmed
- Department of Basic Sciences, University of Veterinary and Animal Sciences Lahore, Sub-campus, Narowal, 51600, Pakistan
| | - Yun-Jian Sheng
- Department of Infectious Diseases, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China.,Southwest Medical University, Jiangyang District, Luzhou, 646000, China
| | - Cun-Liang Deng
- Department of Infectious Diseases, The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, China
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Bai Y, Hao Y, Song Z, Chu W, Jin Y, Wang Y. Evaluation of the Cepheid Xpert C. difficile diagnostic assay: an update meta-analysis. Braz J Microbiol 2021; 52:1937-1949. [PMID: 34455573 PMCID: PMC8578272 DOI: 10.1007/s42770-021-00563-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 06/27/2021] [Indexed: 11/28/2022] Open
Abstract
Background Accurate and rapid diagnosis of Clostridium difficile infection (CDI) is critical for effective patient management and implementation of infection control measures to prevent transmission. Objectives We updated our previous meta-analysis to provide a more reliable evidence base for the clinical diagnosis of Xpert C. difficile (Xpert C. difficile) assay. Methods We searched PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CBM) databases to identify studies according to predetermined criteria. STATA 13.0 software was used to analyze the tests for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curves (AUC). QUADAS-2 was used to assess the quality of included studies with RevMan 5.2. Heterogeneity in accuracy measures was tested with Spearman correlation coefficient and chi-square. Meta-regressions and subgroup analyses were performed to figure out the potential sources of heterogeneity. Model diagnostics were used to evaluate the veracity of the data. Results A total of 26 studies were included in the meta-analysis. The pooled sensitivity (95% confidence intervals [CI]) for diagnosis was 0.97(0.95–0.98), and specificity was 0.96(0.95–0.97). The AUC was 0.99 (0.98–1.00). Model diagnostics confirmed the robustness of our meta-analysis’s results. Significant heterogeneity was still observed when we pooled most of the accuracy measures of selected studies. Meta-regression and subgroup analyses showed that the sample size and type, ethnicity, and disease prevalence might be the conspicuous sources of heterogeneity. Conclusions The up-to-date meta-analysis showed the Xpert CD assay had good accuracy for detecting CDI. However, the diagnosis of CDI must combine clinical presentation with diagnostic testing to better answer the question of whether the patient actually has CDI in the future, and inclusion of preanalytical parameters and clinical outcomes in study design would provide a more objective evidence base.
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Affiliation(s)
- Yuanyuan Bai
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, People's Republic of China
| | - Yingying Hao
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, People's Republic of China
| | - Zhen Song
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, People's Republic of China
| | - Wenjun Chu
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, People's Republic of China
| | - Yan Jin
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, People's Republic of China.
| | - Yueling Wang
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, People's Republic of China.
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Loderstädt U, Hagen RM, Hahn A, Frickmann H. New Developments in PCR-Based Diagnostics for Bacterial Pathogens Causing Gastrointestinal Infections-A Narrative Mini-Review on Challenges in the Tropics. Trop Med Infect Dis 2021; 6:tropicalmed6020096. [PMID: 34199650 PMCID: PMC8293448 DOI: 10.3390/tropicalmed6020096] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 05/31/2021] [Accepted: 05/31/2021] [Indexed: 12/15/2022] Open
Abstract
The application of modern PCR approaches for the diagnosis of bacterial gastrointestinal pathogens is on the rise due to their rapidly available results combined with high sensitivity. While multiple studies describe the ongoing implementation of this technique for routine diagnostic purposes in laboratories in Western industrialized countries, reports on successful and also sustainable respective approaches in resource-poor tropical settings are still scarce. In order to shed light on potential reasons for this marked discrepancy, this narrative review summarizes identified challenges for the application of diagnostic PCR targeting bacterial gastrointestinal pathogens from stool samples in the tropics. The identified and discussed issues comprise the lack of generally accepted definitions for (1) minimum standards regarding sample acquisition, storage and transport time for diagnostic PCR analyses in the tropics, (2) nucleic acid extraction standards allowing an optimum detection of all types of pathogens which may be responsible for gastroenteritis in the tropics, (3) validation standards to ensure comparable quality of applied diagnostic assays, and (4) cut-offs for a reliable discrimination of infection and mere colonization in areas where semi-immunity due to repeated exposition associated with poor hygiene conditions has to be expected. Further implementation research is needed to solve those issues.
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Affiliation(s)
- Ulrike Loderstädt
- Institute for Infection Control and Infectious Diseases, University Medical Center Göttingen, 37075 Göttingen, Germany;
| | - Ralf Matthias Hagen
- Department of Microbiology and Hospital Hygiene, Bundeswehr Central Hospital Koblenz, Andernacher Str. 100, 56070 Koblenz, Germany;
| | - Andreas Hahn
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany;
| | - Hagen Frickmann
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany;
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany
- Correspondence: or or ; Tel.: +49-40-6947-28743
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Tanida K, Hahn A, Frickmann H. Comparison of two commercial and one in-house real-time PCR assays for the diagnosis of bacterial gastroenteritis. Eur J Microbiol Immunol (Bp) 2020; 10:210-216. [PMID: 33279885 PMCID: PMC7753976 DOI: 10.1556/1886.2020.00030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 11/18/2020] [Indexed: 12/14/2022] Open
Abstract
Introduction The aim of the study was a comparative evaluation of in-house real-time PCR and commercial real-time PCR (Fast Track Diagnostics (FTD), ampliCube/Mikrogen) targeting enteropathogenic bacteria from stool in preparation of Regulation (EU) 2017/746 on in vitro diagnostic medical devices. Methods Both 241 stool samples from patients and 100 samples from German laboratory control schemes (“Ringversuche”) were used to comparatively assess in-house real-time PCR, the FTD bacterial gastroenteritis kit, and the ampliCube gastrointestinal bacterial panels 1&2 either with the in-house PCRs as gold standard and as a test comparison without gold standard applying latent class analysis. Sensitivity, specificity, intra- and inter-assay variation and Cohen’s kappa were assessed. Results In comparison with the gold standard, sensitivity was 75–100% for strongly positive samples, 20–100% for weakly positive samples, and specificity ranged from 96 to 100%. Latent class analysis suggested that sensitivity ranges from 81.2 to 100% and specificity from 58.5 to 100%. Cohen’s kappa varied between moderate and nearly perfect agreement, intra- and inter-assay variation was 1–3 to 1–4 Ct values. Conclusion Acceptable agreement and performance characteristics suggested replaceability of the in-house PCR assays by the commercial approaches.
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Affiliation(s)
- Konstantin Tanida
- 1Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | - Andreas Hahn
- 2Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| | - Hagen Frickmann
- 1Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany.,2Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
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Kraft CS, Parrott JS, Cornish NE, Rubinstein ML, Weissfeld AS, McNult P, Nachamkin I, Humphries RM, Kirn TJ, Dien Bard J, Lutgring JD, Gullett JC, Bittencourt CE, Benson S, Bobenchik AM, Sautter RL, Baselski V, Atlas MC, Marlowe EM, Miller NS, Fischer M, Richter SS, Gilligan P, Snyder JW. A Laboratory Medicine Best Practices Systematic Review and Meta-analysis of Nucleic Acid Amplification Tests (NAATs) and Algorithms Including NAATs for the Diagnosis of Clostridioides ( Clostridium) difficile in Adults. Clin Microbiol Rev 2019; 32:32/3/e00032-18. [PMID: 31142497 PMCID: PMC6589859 DOI: 10.1128/cmr.00032-18] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The evidence base for the optimal laboratory diagnosis of Clostridioides (Clostridium) difficile in adults is currently unresolved due to the uncertain performance characteristics and various combinations of tests. This systematic review evaluates the diagnostic accuracy of laboratory testing algorithms that include nucleic acid amplification tests (NAATs) to detect the presence of C. difficile The systematic review and meta-analysis included eligible studies (those that had PICO [population, intervention, comparison, outcome] elements) that assessed the diagnostic accuracy of NAAT alone or following glutamate dehydrogenase (GDH) enzyme immunoassays (EIAs) or GDH EIAs plus C. difficile toxin EIAs (toxin). The diagnostic yield of NAAT for repeat testing after an initial negative result was also assessed. Two hundred thirty-eight studies met inclusion criteria. Seventy-two of these studies had sufficient data for meta-analysis. The strength of evidence ranged from high to insufficient. The uses of NAAT only, GDH-positive EIA followed by NAAT, and GDH-positive/toxin-negative EIA followed by NAAT are all recommended as American Society for Microbiology (ASM) best practices for the detection of the C. difficile toxin gene or organism. Meta-analysis of published evidence supports the use of testing algorithms that use NAAT alone or in combination with GDH or GDH plus toxin EIA to detect the presence of C. difficile in adults. There is insufficient evidence to recommend against repeat testing of the sample using NAAT after an initial negative result due to a lack of evidence of harm (i.e., financial, length of stay, or delay of treatment) as specified by the Laboratory Medicine Best Practices (LMBP) systematic review method in making such an assessment. Findings from this systematic review provide clarity to diagnostic testing strategies and highlight gaps, such as low numbers of GDH/toxin/PCR studies, in existing evidence on diagnostic performance, which can be used to guide future clinical research studies.
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Affiliation(s)
| | - J Scott Parrott
- Department of Interdisciplinary Studies, School of Health Professions, Rutgers University, Newark, New Jersey, USA
- Department of Epidemiology, School of Public Health, Rutgers University, Piscataway, New Jersey, USA
| | - Nancy E Cornish
- Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | | | | | - Peggy McNult
- American Society for Microbiology, Washington, DC, USA
| | - Irving Nachamkin
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Thomas J Kirn
- Department of Interdisciplinary Studies, School of Health Professions, Rutgers University, Newark, New Jersey, USA
- Department of Epidemiology, School of Public Health, Rutgers University, Piscataway, New Jersey, USA
| | - Jennifer Dien Bard
- Children's Hospital Los Angeles, Los Angeles, California, USA
- Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | | | - Jonathan C Gullett
- Kaiser Permanente (Southern California Permanente Medical Group) Regional Reference Laboratories, Greater Los Angeles, Los Angeles, California, USA
| | | | - Susan Benson
- PathWest Laboratory Medicine, Perth, Western Australia, Australia
- University of Western Australia, Perth, Western Australia, Australia
| | - April M Bobenchik
- Rhode Island Hospital/Lifespan Academic Medical Center, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | | | - Vickie Baselski
- University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Michel C Atlas
- Kornhauser Health Sciences Library, University of Louisville, Louisville, Kentucky, USA
| | | | - Nancy S Miller
- Boston Medical Center, Boston, Massachusetts, USA
- Boston University School of Medicine, Boston, Massachusetts, USA
| | | | | | - Peter Gilligan
- University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - James W Snyder
- Kornhauser Health Sciences Library, University of Louisville, Louisville, Kentucky, USA
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Bossi P, Antonuzzo A, Cherny NI, Rosengarten O, Pernot S, Trippa F, Schuler U, Snegovoy A, Jordan K, Ripamonti CI. Diarrhoea in adult cancer patients: ESMO Clinical Practice Guidelines. Ann Oncol 2018; 29:iv126-iv142. [PMID: 29931177 DOI: 10.1093/annonc/mdy145] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- P Bossi
- Head and Neck Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano
| | - A Antonuzzo
- U.O. Oncologia Medica 1, Polo Oncologico Azienda Ospedaliero Universitaria Pisana, Pisa, Italy
| | - N I Cherny
- Oncology Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - O Rosengarten
- Oncology Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - S Pernot
- Department of Hepato-Gastroenterology and Digestive Oncology, Georges Pompidou European Hospital, APHP, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - F Trippa
- Radiation Oncology Centre, "S. Maria" Hospital, Terni, Italy
| | - U Schuler
- Department of Internal Medicine I, Palliative Care Centre, University Hospital Carl Gustav Carus, Dresden, Germany
| | - A Snegovoy
- N.N. Blokhin Russian Cancer Research Center, Moscow, Russia
| | - K Jordan
- Department of Medicine V, Hematology, Oncology and Rheumatology, University of Heidelberg, Heidelberg, Germany
| | - C I Ripamonti
- Oncology-Supportive Care in Cancer Unit, Department Onco-Haematology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
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Cho SH, Chon JW, Seo KH, Kim YK, Kim JB, Bak YS, Jung WW, Kim CH, Choi JT. Characterization of Clostridium difficile Strains Isolated from Patients with C. difficile-associated Disease in Korea. Osong Public Health Res Perspect 2017; 8:325-331. [PMID: 29164044 PMCID: PMC5678197 DOI: 10.24171/j.phrp.2017.8.5.06] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 09/19/2017] [Accepted: 09/25/2017] [Indexed: 12/30/2022] Open
Abstract
Objectives Studies on Clostridium difficile are rare in Korea. We investigated the epidemiological characteristics of C. difficile isolates from patients with C. difficile-associated disease (CDAD) in Korea. Methods Multiplex polymerase chain reaction was performed to detect the presence of tcdA and tcdB toxin genes. Antimicrobial susceptibility test was carried out by the disk-dilution method. C. difficile strains were subtyped by automated repetitive-element palindromic PCR (rep-PCR). Results Among patients with CDAD, 73 (25.8%), 32 (11.3%), 32 (11.3%), and 26 (9.2%) suffered from pneumonia, cancer or neoplasm, diabetes, and colitis, respectively. Of all stool samples, 43 samples (15.2%) were positive for C. difficile strains. We observed two expression patterns of toxin genes: tcdA+/tcdB+ (86% isolates) and tcdA-/tcdB+ (14% isolates), with all isolates expressing tcdB. Furthermore, some isolates were resistant to clindamycin (65%), ampicillin (56%), and cefazolin (40%), but all were susceptible to vancomycin and metronidazole. The tested samples were classified into diverse clusters using automated rep-PCR. Conclusion Our findings revealed the characteristics and antibiotic resistance of C. difficile isolates from patients in Korea. The epidemiological data may provide valuable insight into development of treatment strategies for C. difficile infections in Korea.
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Affiliation(s)
- Seung-Hak Cho
- Division of Bacterial Disease Research, Center for Infectious Disease Research, Korea National Institute of Health, Cheongju, Korea
| | - Jung-Whan Chon
- KU Center for Food Safety, College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Kun-Ho Seo
- KU Center for Food Safety, College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Young Kwon Kim
- Department of Biomedical Laboratory Science, College of Medical Sciences, Konyang University, Daejeon, Korea
| | - Jung-Beom Kim
- Department of Food Science and Technology, Sunchon National University, Suncheon, Korea
| | - Young-Seok Bak
- Department of Emergency Medical Services, Sun Moon University, Asan, Korea
| | - Woon-Won Jung
- Department of Biomedical Laboratory, Science College of Health Science, Cheongju University, Cheongju, Korea
| | - Cheorl-Ho Kim
- Glycobiology Unit, Department of Biological Science, Sungkyunkwan University and Samsung Advanced Institute for Health Science and Technology (SAIHST), Suwon, Korea
| | - Jong Tae Choi
- Department of Biomedical Laboratory Science, Kyungdong University, Wonju, Korea
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Bai Y, Sun X, Jin Y, Wang Y, Li J. Accuracy of Xpert Clostridium difficile assay for the diagnosis of Clostridium difficile infection: A meta analysis. PLoS One 2017; 12:e0185891. [PMID: 29016644 PMCID: PMC5633177 DOI: 10.1371/journal.pone.0185891] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 09/21/2017] [Indexed: 12/18/2022] Open
Abstract
Background There is an urgent need for rapid and accurate microbiological diagnostic assay for detection of Clostridium difficile infection (CDI). We assessed the diagnostic accuracy of the Xpert Clostridium difficile assay (Xpert CD) for the diagnosis of CDI. Methods We searched PubMed, EMBASE, and Cochrane Library databases to identify studies according to predetermined criteria. STATA 13.0 software was used to analyze the tests for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curves (AUC). QUADAS-2 was used to assess the quality of included studies with RevMan 5.2. Heterogeneity in accuracy measures was tested with Spearman correlation coefficient and Chi-square. Results A total of 22 studies were included in the meta-analysis. The pooled sensitivity (95% confidence intervals [CI]) was 0.97 (0.95–0.99) and specificity was 0.95 (0.94–0.96). The AUC was 0.99 (0.97–0.99). Significant heterogeneity was observed when we pooled most of the accuracy measures of selected studies. Conclusions The Xpert CD assay is a useful diagnostic tool with high sensitivity and specificity in diagnosing toxigenic CDI, and this method has excellent usability due to its rapidity and simplicity.
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Affiliation(s)
- Yuanyuan Bai
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, PR China
| | - Xiaorong Sun
- Department of Pathology, Jinan Women and Children’s Health Hospital, Jinan, PR China
| | - Yan Jin
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, PR China
| | - Yueling Wang
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, PR China
| | - Juan Li
- Department of Pathology, Jinan Women and Children’s Health Hospital, Jinan, PR China
- * E-mail:
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Martínez-Meléndez A, Camacho-Ortiz A, Morfin-Otero R, Maldonado-Garza HJ, Villarreal-Treviño L, Garza-González E. Current knowledge on the laboratory diagnosis of Clostridium difficile infection. World J Gastroenterol 2017; 23:1552-1567. [PMID: 28321156 PMCID: PMC5340807 DOI: 10.3748/wjg.v23.i9.1552] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/21/2017] [Accepted: 02/17/2017] [Indexed: 02/06/2023] Open
Abstract
Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is characterized by diarrhea in clinical syndromes that vary from self-limited to mild or severe. Since its initial recognition as the causative agent of pseudomembranous colitis, C. difficile has spread around the world. CDI is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Due to extensive antibiotic usage, the number of CDIs has increased. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with the disease, mainly with regards to antibiotic management. The diagnosis of CDI is primarily based on the clinical signs and symptoms and is only confirmed by laboratory testing. Despite the high burden of CDI and the increasing interest in the disease, episodes of CDI are often misdiagnosed. The reasons for misdiagnosis are the lack of clinical suspicion or the use of inappropriate tests. The proper diagnosis of CDI reduces transmission, prevents inadequate or unnecessary treatments, and assures best antibiotic treatment. We review the options for the laboratory diagnosis of CDI within the settings of the most accepted guidelines for CDI diagnosis, treatment, and prevention of CDI.
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12
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Chronic Diarrhea. Infect Dis (Lond) 2017. [DOI: 10.1016/b978-0-7020-6285-8.00039-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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13
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Crobach MJT, Planche T, Eckert C, Barbut F, Terveer EM, Dekkers OM, Wilcox MH, Kuijper EJ. European Society of Clinical Microbiology and Infectious Diseases: update of the diagnostic guidance document for Clostridium difficile infection. Clin Microbiol Infect 2016; 22 Suppl 4:S63-81. [PMID: 27460910 DOI: 10.1016/j.cmi.2016.03.010] [Citation(s) in RCA: 362] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/02/2016] [Accepted: 03/10/2016] [Indexed: 12/14/2022]
Abstract
In 2009 the first European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guideline for diagnosing Clostridium difficile infection (CDI) was launched. Since then newer tests for diagnosing CDI have become available, especially nucleic acid amplification tests. The main objectives of this update of the guidance document are to summarize the currently available evidence concerning laboratory diagnosis of CDI and to formulate and revise recommendations to optimize CDI testing. This update is essential to improve the diagnosis of CDI and to improve uniformity in CDI diagnosis for surveillance purposes among Europe. An electronic search for literature concerning the laboratory diagnosis of CDI was performed. Studies evaluating a commercial laboratory test compared to a reference test were also included in a meta-analysis. The commercial tests that were evaluated included enzyme immunoassays (EIAs) detecting glutamate dehydrogenase, EIAs detecting toxins A and B and nucleic acid amplification tests. Recommendations were formulated by an executive committee, and the strength of recommendations and quality of evidence were graded using the Grades of Recommendation Assessment, Development and Evaluation (GRADE) system. No single commercial test can be used as a stand-alone test for diagnosing CDI as a result of inadequate positive predictive values at low CDI prevalence. Therefore, the use of a two-step algorithm is recommended. Samples without free toxin detected by toxins A and B EIA but with positive glutamate dehydrogenase EIA, nucleic acid amplification test or toxigenic culture results need clinical evaluation to discern CDI from asymptomatic carriage.
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Affiliation(s)
- M J T Crobach
- Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - T Planche
- Department of Medical Microbiology, St. George's Hospital, London, UK
| | - C Eckert
- National Reference Laboratory for Clostridium difficile, Paris, France
| | - F Barbut
- National Reference Laboratory for Clostridium difficile, Paris, France
| | - E M Terveer
- Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - O M Dekkers
- Departments of Clinical Epidemiology and Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands; Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark
| | - M H Wilcox
- Department of Microbiology, Leeds Teaching Hospitals & University of Leeds, Leeds, UK
| | - E J Kuijper
- Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands.
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Sandell S, Rashid MU, Jorup-Rönström C, Ellström K, Nord CE, Weintraub A. Clostridium difficile recurrences in Stockholm. Anaerobe 2016; 38:97-102. [PMID: 26802875 DOI: 10.1016/j.anaerobe.2016.01.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 01/11/2016] [Accepted: 01/19/2016] [Indexed: 02/07/2023]
Abstract
Sixty-eight hospital-admitted patients with a first episode of Clostridium difficile infection (CDI) were included and followed up during 1 year. Faeces samples were collected at 1, 2, 6 and 12 months after inclusion and analyzed for the presence of C. difficile toxin B, genes for toxin A, toxin B, binary toxin and TcdC deletion by PCR. All strains were also PCR-ribotyped and the MICs of the isolates were determined against eight antimicrobial agents. In 68 patients initially included, antibiotics, clinical signs and co-morbidities were analyzed and 56 were evaluable for recurrences. The mean number of different antibiotics given during 3 months prior to inclusion was 2.6 (range 0-6). Six patients had not received any antibiotics and three of them had diagnosed inflammatory bowel disease. Thirty-two patients (57%) had either a microbiological or clinical recurrence, 16 of whom had clinical recurrences that were confirmed microbiologically (13, 23%) or unconfirmed by culture (3, 5%). Twenty-nine patients were positive in at least one of the follow-up tests, 16 had the same ribotype in follow-up tests, i.e. relapse, and 13 a different ribotype, i.e., reinfection. Most common ribotypes were 078/126, 020, 023, 026, 014/077, 001 and 005. No strain of ribotype 027 was found. Strains ribotype 078/126 and 023 were positive for binary toxin and were the strains most prone to cause recurrence. All strains were sensitive to vancomycin and metronidazole. Patients with recurrences were significantly older (p = 0.02) and all patients had a high burden of comorbidities, which could explain the high fatality rate, 26 (38%) patients died during the 1-year follow-up.
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Affiliation(s)
- Staffan Sandell
- Karolinska Institutet, Department of Medicine, Division of Infectious Diseases, Södersjukhuset, SE-118 83 Stockholm, Sweden
| | - Mamun-Ur Rashid
- Karolinska Institutet, Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital Huddinge, SE-141 86 Stockholm, Sweden
| | - Christina Jorup-Rönström
- Karolinska Institutet, Department of Medicine, Division of Infectious Diseases, Södersjukhuset, SE-118 83 Stockholm, Sweden
| | - Kristina Ellström
- Karolinska Institutet, Department of Medicine, Division of Infectious Diseases, Södersjukhuset, SE-118 83 Stockholm, Sweden
| | - Carl Erik Nord
- Karolinska Institutet, Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital Huddinge, SE-141 86 Stockholm, Sweden.
| | - Andrej Weintraub
- Karolinska Institutet, Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital Huddinge, SE-141 86 Stockholm, Sweden
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15
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Aldrete SDM, Magee MJ, Friedman-Moraco RJ, Chan AW, Banks GG, Burd EM, Kraft CS. Characteristics and Antibiotic Use Associated With Short-Term Risk of Clostridium difficile Infection Among Hospitalized Patients. Am J Clin Pathol 2015; 143:895-900. [PMID: 25972333 DOI: 10.1309/ajcp9ewi6qpvtpqy] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVES Polymerase chain reaction (PCR) has been shown to have an excellent sensitivity and specificity for the detection of Clostridium difficile infection (CDI). Little is known about risk factors for CDI within 14 days of an initial negative test. We sought to determine the characteristics among hospitalized patients associated with risk of short-term acquisition of CDI. METHODS A case-control study was conducted. Cases were patients who converted from PCR negative to positive within 14 days. Each case was matched with three controls. Conditional logistic regression was used to estimate the association between patient characteristics and CDI. RESULTS Of the 30 patients in our study who had a positive PCR within 14 days of a first negative PCR (cases), 15 (50%) occurred within 7 days of the initial test. Cases had a higher proportion of intravenous vancomycin use in the previous 8 weeks (odds ratio [OR], 3.38; 95% confidence interval [CI], 1.34-8.49) and were less likely to have recent antiviral agent use (OR, 0.30; 95% CI, 0.11-0.83) compared with controls. CONCLUSIONS In hospitalized patients, treatment with intravenous vancomycin within the prior 8 weeks of a first negative PCR test for C difficile is a risk factor for short-term risk for hospital-acquired CDI. Repeat testing guidelines for C difficile PCR should take into consideration patients who may be at high risk for short-term acquisition of CDI.
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Affiliation(s)
- Sol del Mar Aldrete
- Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA
| | - Matthew J. Magee
- Division of Epidemiology and Biostatistics, Georgia State University School of Public Health, Atlanta
| | | | - Austin W. Chan
- Division of Infectious Diseases, Duke University, Durham, NC
| | | | - Eileen M. Burd
- Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA
| | - Colleen S. Kraft
- Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA
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Leibowitz J, Soma VL, Rosen L, Ginocchio CC, Rubin LG. Similar proportions of stool specimens from hospitalized children with and without diarrhea test positive for Clostridium difficile. Pediatr Infect Dis J 2015; 34:261-6. [PMID: 25247582 DOI: 10.1097/inf.0000000000000556] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Many laboratories use polymerase chain reaction (PCR)-based assays to detect the Clostridium difficile toxin B gene (tcdB) in stool. However, PCR testing experience in pediatric patients is limited. We compared the detection of C. difficile by PCR in hospitalized children with and without diarrhea. METHODS Stool samples from patients aged 1-18 years with diarrhea (symptomatic) and from patients without diarrhea (asymptomatic) were tested for C. difficile tcdB using a commercial PCR assay. Samples were cultured for C. difficile using standard techniques with tcdB PCR and cytotoxicity assays performed on C. difficile isolates. Demographic, clinical and laboratory data were abstracted. Categorical and continuous variables were compared between the 2 groups using Fisher Exact test and the Mann-Whitney test, respectively. RESULTS Thirty-five of 188 (19%) stool samples from symptomatic patients and 18 of 74 (24%) samples from asymptomatic patients were positive by PCR (P=0.31). Among PCR-positive patients, symptomatic patients had a significantly higher proportion of subjects who received antimicrobials in the preceding 30 days (P=0.04) and a greater number of preceding antimicrobial days than did asymptomatic patients (P=0.02) but were comparable with respect to the other variables analyzed. CONCLUSIONS C. difficile PCR assays are frequently positive in hospitalized children both with and without diarrhea. As we observed a high level of toxigenic C. difficile colonization in children, our findings suggest that a positive C. difficile PCR result in a child with diarrhea should be interpreted with caution.
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Affiliation(s)
- Jill Leibowitz
- From the *Division of Infectious Diseases, Department of Pediatrics, Steven and Alexandra Cohen Children's Medical Center, ‡Department of Biostatistics, Feinstein Institute for Medical Research, and §Division of Infectious Disease Diagnostics, Department of Pathology and Laboratory Medicine, North Shore Long Island Jewish Health System, New Hyde Park, New York; †Hofstra North Shore Long Island Jewish School of Medicine, Hempstead, New York
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Comparison of GenomEra C. difficile and Xpert C. difficile as confirmatory tests in a multistep algorithm for diagnosis of Clostridium difficile infection. J Clin Microbiol 2014; 53:332-5. [PMID: 25392360 DOI: 10.1128/jcm.03093-14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
We compared two multistep diagnostic algorithms based on C. Diff Quik Chek Complete and, as confirmatory tests, GenomEra C. difficile and Xpert C. difficile. The sensitivity, specificity, positive predictive value, and negative predictive value were 87.2%, 99.7%, 97.1%, and 98.3%, respectively, for the GenomEra-based algorithm and 89.7%, 99.4%, 95.5%, and 98.6%, respectively, for the Xpert-based algorithm. GenomEra represents an alternative to Xpert as a confirmatory test of a multistep algorithm for Clostridium difficile infection (CDI) diagnosis.
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18
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Kubota H, Sakai T, Gawad A, Makino H, Akiyama T, Ishikawa E, Oishi K. Development of TaqMan-based quantitative PCR for sensitive and selective detection of toxigenic Clostridium difficile in human stools. PLoS One 2014; 9:e111684. [PMID: 25360662 PMCID: PMC4216139 DOI: 10.1371/journal.pone.0111684] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 10/07/2014] [Indexed: 01/05/2023] Open
Abstract
Background Clostridium difficile is the main cause of nosocomial diarrhea, but is also found in asymptomatic subjects that are potentially involved in transmission of C. difficile infection. A sensitive and accurate detection method of C. difficile, especially toxigenic strains is indispensable for the epidemiological investigation. Methods TaqMan-based quantitative-PCR (qPCR) method for targeting 16S rRNA, tcdB, and tcdA genes of C. difficile was developed. The detection limit and accuracy of qPCR were evaluated by analyzing stool samples spiked with known amounts of C. difficile. A total of 235 stool specimens collected from 82 elderly nursing home residents were examined by qPCR, and the validity was evaluated by comparing the detection result with that by C. difficile selective culture (CDSC). Results The analysis of C. difficile-spiked stools confirmed that qPCR quantified whole C. difficile (TcdA+TcdB+, TcdA−TcdB+, and TcdA−TcdB− types), TcdB-producing strains (TcdA+TcdB+ and TcdA−TcdB+ types), and TcdA-producing strains (TcdA+TcdB+ type), respectively, with a lower detection limit of 103 cells/g of stool. Of the 235 specimens examined, 12 specimens (5.1%) were C. difficile-positive by qPCR: TcdA+TcdB+ strain in six specimens and TcdA−TcdB− strain in the other six. CDSC detected C. difficile in 9 of the 12 specimens, and toxigenic types of the isolates from the 9 specimens were consistent with those identified by qPCR, supporting the validity of our qPCR method. Moreover, the qPCR examination revealed that the carriage rate of whole C. difficile and that of toxigenic strains in the 82 subjects over a 6-month period ranged from 2.4 to 6.8% and 1.2 to 3.8%, respectively. An average qPCR count of C. difficile detected was 104.5 cells/g of stool, suggesting that C. difficile constituted a very small fraction of intestinal microbiota. Conclusion Our qPCR method should be an effective tool for both clinical diagnosis and epidemiological investigation of C. difficile.
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Affiliation(s)
- Hiroyuki Kubota
- Yakult Honsha European Research Center for Microbiology ESV, Gent-Zwijnaarde, Belgium
- Yakult Central Institute, Tokyo, Japan
- * E-mail:
| | | | - Agata Gawad
- Yakult Honsha European Research Center for Microbiology ESV, Gent-Zwijnaarde, Belgium
| | | | - Takuya Akiyama
- Yakult Honsha European Research Center for Microbiology ESV, Gent-Zwijnaarde, Belgium
- Yakult Central Institute, Tokyo, Japan
| | | | - Kenji Oishi
- Yakult Honsha European Research Center for Microbiology ESV, Gent-Zwijnaarde, Belgium
- Yakult Central Institute, Tokyo, Japan
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19
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Buxey KN, Sia C, Bell S, Wale R, Wein D, Warrier SK. Clostridium colitis: challenges in diagnosis and treatment. ANZ J Surg 2014; 87:227-231. [DOI: 10.1111/ans.12840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2014] [Indexed: 11/26/2022]
Affiliation(s)
- Kenneth N. Buxey
- Department of Colorectal Surgery; The Alfred Hospital; Melbourne Victoria Australia
| | - Chris Sia
- Department of Colorectal Surgery; The Alfred Hospital; Melbourne Victoria Australia
| | - Stephen Bell
- Department of Colorectal Surgery; The Alfred Hospital; Melbourne Victoria Australia
| | - Roger Wale
- Department of Colorectal Surgery; The Alfred Hospital; Melbourne Victoria Australia
| | - Daniel Wein
- Department of Colorectal Surgery; The Alfred Hospital; Melbourne Victoria Australia
| | - Satish K. Warrier
- Department of Colorectal Surgery; The Alfred Hospital; Melbourne Victoria Australia
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20
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Pawlowski SW. Clostridium difficile Infection Update for the Hospital-Based Physician. CURRENT EMERGENCY AND HOSPITAL MEDICINE REPORTS 2014. [DOI: 10.1007/s40138-014-0053-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sewell B, Rees E, Thomas I, Ch'ng CL, Isaac M, Berry N. Cost and Impact on Patient Length of Stay of Rapid Molecular Testing for Clostridium difficile. Infect Dis Ther 2014; 3:281-93. [PMID: 25183400 PMCID: PMC4269620 DOI: 10.1007/s40121-014-0034-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Indexed: 12/18/2022] Open
Abstract
Introduction A study was performed to assess the cost of a rapid molecular assay (PCR) for diagnosis of Clostridium difficile infection (CDI) and the impact of its routine use on patient length of stay (LOS) in comparison with cell culture cytotoxin neutralization assay (CCNA). Methods From March 2011 to September 2011, Xpert®C. difficile (Cepheid, Sunnyvale, CA, USA) PCR was used on patients with suspicion of CDI in two acute care hospitals in Abertawe Bro Morgannwg University Health Board, Swansea, Wales, UK. Test results were used for patient management. LOS and time to reportable result were compared for negative and positive prospective patients tested by PCR and historic control patients tested by CCNA during March 2010 to September 2010. Tests were priced using micro-costing and a cost comparison analysis was undertaken. Results In total, 506 patients were included. Time to reportable result for PCR samples was 1.53 h compared to 46.54 h for CCNA negatives and 22.45 h for CCNA positives. Patients tested by CCNA stayed 4.88 days longer in hospital compared to PCR patients if they tested positive and 7.03 days if tests were negative. The mean reduction in LOS observed in our study has the potential to generate cost savings of up to £2,292.62 for every patient with suspected CDI, if samples were to be tested routinely with PCR instead of CCNA. Conclusion A rapid molecular test for C. difficile in an acute hospital setting produced quick results that led to a decrease in LOS compared to historic CCNA control patients. This could result in considerable savings through reduced excess inpatient days. Electronic supplementary material The online version of this article (doi:10.1007/s40121-014-0034-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bernadette Sewell
- Swansea Centre for Health Economics, College of Human and Health Sciences, Swansea University, Singleton Park, Swansea, UK.
| | - Eugene Rees
- Public Health Wales, Microbiology ABMUHB, Singleton Hospital, Swansea, UK
| | - Ian Thomas
- Public Health Wales, Microbiology ABMUHB, Singleton Hospital, Swansea, UK
| | - Chin Lye Ch'ng
- Gastroenterology Department, Singleton Hospital, Swansea, UK
| | - Mike Isaac
- Public Health Wales, Microbiology ABMUHB, Singleton Hospital, Swansea, UK
| | - Nidhika Berry
- Public Health Wales, Microbiology ABMUHB, Singleton Hospital, Swansea, UK
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Clinical characteristics of patients who test positive for Clostridium difficile by repeat PCR. J Clin Microbiol 2014; 52:3853-5. [PMID: 25122866 DOI: 10.1128/jcm.01659-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The high sensitivity of PCR assays for diagnosing Clostridium difficile infection (CDI) has greatly reduced the need for repeat testing after a negative result. Nevertheless, a small subset of patients do test positive within 7 days of a negative test. The aim of this study was to evaluate the clinical characteristics of these patients to determine when repeat testing may be appropriate. The results of all Xpert C. difficile PCR (Cepheid, Sunnyvale CA) tests performed in the clinical microbiology laboratory at New York-Presbyterian Hospital, Columbia University Medical Center (NYPH/CUMC) from 1 May 2011 through 6 September 2013, were reviewed. A retrospective case-control study was performed, comparing patients who tested positive within 7 days of a negative test result to a random selection of 50 controls who tested negative within 7 days of a negative test result. During the study period, a total of 14,875 tests were performed, of which 1,066 were repeat tests (7.2%). Eleven of these repeat tests results were positive (1.0%). The only risk factor independently associated with repeat testing positive was history of a prior CDI (odds ratio [OR], 19.6 [95% confidence interval {CI}, 4.0 to 19.5], P < 0.001). We found that patients who test positive for C. difficile by PCR within 7 days of a negative test are more likely to have a history of CDI than are patients who test negative with repeat PCR. This finding may be due to the high rate of disease relapse or the increased likelihood of empirical therapy leading to false-negative results in these patients.
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Rashid MU, Dalhoff A, Weintraub A, Nord CE. In vitro activity of MCB3681 against Clostridium difficile strains. Anaerobe 2014; 28:216-9. [DOI: 10.1016/j.anaerobe.2014.07.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 06/30/2014] [Accepted: 07/02/2014] [Indexed: 02/06/2023]
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Rashid MU, Dalhoff A, Bäckström T, Björkhem-Bergman L, Panagiotidis G, Weintraub A, Nord CE. Ecological impact of MCB3837 on the normal human microbiota. Int J Antimicrob Agents 2014; 44:125-30. [PMID: 24931053 DOI: 10.1016/j.ijantimicag.2014.03.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/26/2014] [Accepted: 03/30/2014] [Indexed: 11/30/2022]
Abstract
MCB3837 is a novel, water-soluble, injectable prodrug that is rapidly converted to the active substance MCB3681 in vivo following intravenous (i.v.) administration. Both MCB3837 and MCB3681 are oxazolidinone-quinolone hybrid molecules. The purpose of the present study was to investigate the effect of MCB3681 on the human skin, nose, oropharyngeal and intestinal microbiota following administration of MCB3837. Twelve healthy male subjects received i.v. MCB3837 (6 mg/kg body weight) once daily for 5 days. Skin, nose, saliva and faecal samples were collected on Day -1 (pre dose), during administration on Days 2 and 5, and post dose on Days 8, 12 and 19. Micro-organisms were identified to genus level. No measurable concentrations of MCB3681 were found in any saliva samples or in the faecal samples on Day -1. On Day 2, 10 volunteers had faecal MCB3681 concentrations between 16.5 mg/kg faeces and 275.1mg/kg faeces; no MCB3681 in faeces could be detected in two of the volunteers. On Day 5, all volunteers had faecal concentrations of MCB3681 ranging from 98.9 to 226.3 mg/kg. MCB3681 caused no ecological changes in the skin, nasal and oropharyngeal microbiota. The numbers of enterococci, bifidobacteria, lactobacilli and clostridia decreased in the intestinal microbiota during administration of the drug. Numbers of Escherichia coli, other enterobacteria and Candida were not affected during the study. There was no impact on the number of Bacteroides. The faecal microbiota was normalised on Day 19. No new colonising aerobic or anaerobic Gram-positive bacteria with MCB3681 minimum inhibitory concentrations of ≥4 mg/L were found.
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Affiliation(s)
- Mamun-Ur Rashid
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Axel Dalhoff
- University Medical Center Schleswig-Holstein, Institute for Infection Medicine, Brunswiker Str. 4, D-24105 Kiel, Germany
| | - Tobias Bäckström
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Linda Björkhem-Bergman
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Georgios Panagiotidis
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Andrej Weintraub
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Carl Erik Nord
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden.
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25
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Abstract
Gastroenteritis persists as a worldwide problem, responsible for approximately 2 million deaths annually. Traditional diagnostic methods used in the clinical microbiology laboratory include a myriad of tests, such as culture, microscopy, and immunodiagnostics, which can be labor intensive and suffer from long turnaround times and, in some cases, poor sensitivity. [corrected]. This article reviews recent advances in genomic and proteomic technologies that have been applied to the detection and identification of gastrointestinal pathogens. These methods simplify and speed up the detection of pathogenic microorganisms, and their implementation in the clinical microbiology laboratory has potential to revolutionize the diagnosis of gastroenteritis.
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26
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Johnson S. Editorial Commentary: Changing Epidemiology of Clostridium difficile and Emergence of New Virulent Strains. Clin Infect Dis 2014; 58:1731-3. [DOI: 10.1093/cid/ciu205] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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Freedberg DE, Salmasian H, Friedman C, Abrams JA. Proton pump inhibitors and risk for recurrent Clostridium difficile infection among inpatients. Am J Gastroenterol 2013; 108:1794-801. [PMID: 24060760 PMCID: PMC3966060 DOI: 10.1038/ajg.2013.333] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 06/08/2013] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Observational studies suggest that proton pump inhibitors (PPIs) are a risk factor for incident Clostridium difficile infection (CDI). Data also suggest an association between PPIs and recurrent CDI, although large-scale studies focusing solely on hospitalized patients are lacking. We therefore performed a retrospective cohort analysis of inpatients with incident CDI to assess receipt of PPIs as a risk factor for CDI recurrence in this population. METHODS Using electronic medical records, we identified hospitalized adult patients between 1 December 2009 and 30 June 2012 with incident CDI, defined as a first positive stool test for C. difficile toxin B and who received appropriate treatment. Electronic records were parsed for clinical factors including receipt of PPIs, other acid suppression, non-CDI antibiotics, and comorbidities. The primary exposure was in-hospital PPIs given concurrently with C. difficile treatment. Recurrence was defined as a second positive stool test 15-90 days after the initial positive test. C. difficile recurrence rates in the PPI exposed and unexposed groups were compared with the log-rank test. Multivariable Cox proportional hazards modeling was performed to control for demographics, comorbidities, and other clinical factors. RESULTS We identified 894 inpatients with incident CDI. The cumulative incidence of CDI recurrence in the cohort was 23%. Receipt of PPIs concurrent with CDI treatment was not associated with C. difficile recurrence (hazard ratio (HR)=0.82; 95% confidence interval (CI)=0.58-1.16). Black race (HR=1.66, 95% CI=1.05-2.63), increased age (HR=1.02, 95% CI=1.01-1.03), and increased comorbidities (HR=1.09, 95% CI=1.04-1.14) were associated with CDI recurrence. In light of a higher 90-day mortality seen among those who received PPIs (log-rank P=0.02), we also analyzed the subset of patients who survived to 90 days of follow-up. Again, there was no association between PPIs and CDI recurrence (HR=0.87; 95% CI=0.60-1.28). Finally, there was no association between recurrent CDI and increased duration or dose of PPIs. CONCLUSIONS Among hospitalized adults with C. difficile, receipt of PPIs concurrent with C. difficile treatment was not associated with CDI recurrence. Black race, increased age, and increased comorbidities significantly predicted recurrence. Future studies should test interventions to prevent CDI recurrence among high-risk inpatients.
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Affiliation(s)
- Daniel E. Freedberg
- Division of Digestive and Liver Diseases, Columbia University Medical Center, New York, New York, USA
| | - Hojjat Salmasian
- Department of Biomedical Informatics, Columbia University, New York, New York, USA
| | - Carol Friedman
- Department of Biomedical Informatics, Columbia University, New York, New York, USA
| | - Julian A. Abrams
- Division of Digestive and Liver Diseases, Columbia University Medical Center, New York, New York, USA
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Toxin-producing Clostridium difficile strains as long-term gut colonizers in healthy infants. J Clin Microbiol 2013; 52:173-9. [PMID: 24172156 DOI: 10.1128/jcm.01701-13] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Clostridium difficile is a colonizer of the human gut, and toxin-producing strains may cause diarrhea if the infectious burden is heavy. Infants are more frequently colonized than adults, but they rarely develop C. difficile disease. It is not known whether strains of C. difficile differ in the capacity to colonize and persist in the human gut microbiota. Here, we strain typed isolates of C. difficile that had colonized 42 healthy infants followed from birth to ≥12 months of age by using PCR ribotyping of the 16S-23S rRNA intergenic spacer region. The isolates were also characterized regarding carriage of the toxin genes tcdA, tcdB, and cdtA/B and the capacity to produce toxin B in vitro. Most strains (71%) were toxin producers, and 51% belonged to the 001 or 014 ribotypes, which often cause disease in adults. These ribotypes were significantly more likely than others to persist for ≥6 months in the infant micobiota, and they were isolated from 13/15 children carrying such long-term-colonizing strains. Ribotype 001 strains were often acquired in the first week of life and attained higher population counts than other C. difficile ribotypes in newborn infants' feces. Several toxin-negative ribotypes were identified, two of which (GI and GIII) were long-term colonizers, each found in one infant. Our results suggest that the toxin-producing C. difficile ribotypes 001 and 014 have special fitness in the infantile gut microbiota. Toxin-producing strains colonizing young children for long time periods may represent a reservoir for strains causing disease in adults.
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Álvarez-Pérez S, Blanco JL, Peláez T, Astorga RJ, Harmanus C, Kuijper E, García ME. High prevalence of the epidemic Clostridium difficile PCR ribotype 078 in Iberian free-range pigs. Res Vet Sci 2013; 95:358-61. [DOI: 10.1016/j.rvsc.2013.06.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/20/2013] [Accepted: 06/25/2013] [Indexed: 02/04/2023]
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Pallis A, Jazayeri J, Ward P, Dimovski K, Svobodova S. Rapid detection of Clostridium difficile toxins from stool samples using real-time multiplex PCR. J Med Microbiol 2013; 62:1350-1356. [DOI: 10.1099/jmm.0.058339-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
In this study, a total of 650 stool samples were tested to show that our method is capable of detecting four Clostridium difficile genes; tcdA, tcdB, encoding toxin A (TcdA) and toxin B (TcdB), and the binary toxin C. difficile transferase genes (cdtA and/or cdtB) encoding CDT toxin. Besides detecting the targeted C. difficile genes, our method can be used to detect the presence of any inhibitory components in the PCR. This assay, combined with a selective culture medium, such as the chromID™ C. difficile, can be applied directly for screening C. difficile-associated disease. The PCR-based assay developed here is rapid (4 h per 21 stool samples) and accurate in diagnosing C. difficile infection, 100 % assay sensitivity and negative predictive value (NPV) were obtained. However, the assay specificity of 99.1 % and positive predictive value (PPV) of 94.9 % were slightly lower than the optimal value of 100 %. The assay protocol outlined here can be used as a rapid screening tool to assist infection control units and in managing infected patients by reducing the number of patients requiring isolation and extended hospitalization. Rapid detection can prevent unnecessary antibiotic therapy and potentially reduce the spread of infection by emerging hypervirulent C. difficile strains.
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Affiliation(s)
- Ann Pallis
- Molecular Diagnostic and Microbiology Laboratory, Austin Pathology, Melbourne, VIC 3084, Australia
| | - Jalal Jazayeri
- School of Biomedical Sciences, Charles Sturt University, Boorooma Street, Wagga Wagga, NSW 2678, Australia
| | - Peter Ward
- Molecular Diagnostic and Microbiology Laboratory, Austin Pathology, Melbourne, VIC 3084, Australia
| | | | - Suzanne Svobodova
- Molecular Diagnostic and Microbiology Laboratory, Austin Pathology, Melbourne, VIC 3084, Australia
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Alerting physicians during electronic order entry effectively reduces unnecessary repeat PCR testing for Clostridium difficile. J Clin Microbiol 2013; 51:3872-4. [PMID: 23985918 DOI: 10.1128/jcm.01724-13] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hospital information systems (HIS) alerts restricting repeat Clostridium difficile PCR ordering by physicians in patients with a prior result within 7 days eliminated 91% of repeat tests, from 14.5% (282/1,949) repeats preintervention to 1.3% (135/10,285) postintervention. HIS alerting is an effective, targeted, patient-specific tool for improving the quality and utilization of C. difficile results.
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Diagnostic accuracy of a multiplex real-time PCR to predict Clostridium difficile ribotype 027. Anaerobe 2013; 22:115-7. [DOI: 10.1016/j.anaerobe.2013.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 03/29/2013] [Accepted: 04/01/2013] [Indexed: 11/17/2022]
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33
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Leis JA, Gold WL, Ng J, Hirji Z, Pillai DR, Broukhanski G, Raggiunti P, Hota S, McGeer A, Poutanen SM. Indeterminate tcdB using a Clostridium difficile PCR assay: a retrospective cohort study. BMC Infect Dis 2013; 13:324. [PMID: 23865713 PMCID: PMC3718660 DOI: 10.1186/1471-2334-13-324] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 07/08/2013] [Indexed: 01/05/2023] Open
Abstract
Background C. difficile (CD) real-time polymerase chain reaction (PCR) for toxin B gene (tcdB) is more sensitive, and reduces turnaround time when compared to toxin immunoassay. We noted typical amplification curves with high tcdB cycle thresholds (Ct) and low endpoints (Ept) that are labeled negative by the Xpert® C. difficile assay (Cepheid) and undertook this study to determine their significance. Methods We defined an indeterminate CD assay result as detection of a typical PCR amplification curve with an Ept >10 that was interpreted as negative by the Xpert® assay. Samples with indeterminate Xpert® result were collected for 5 months and retested by Xpert®, cultured for toxigenic CD, and isolates subjected to PCR ribotyping, detection of toxin genes and multilocus variable-number tandem repeat analysis (MLVA) typing. Chart reviews were completed to assess if patients met the Society of Healthcare Epidemiology of America and the Infectious Diseases Society of America CD infection (CDI) clinical case definition. Illness severity was compared with tcdB Ct and culture results. Results During the 5-month study period, 48/3620 (1%) of specimens were indeterminate and 387/3620 (11%) were positive. Of the 48 patients with indeterminate results, 39 (81%) met the clinical case definition of CDI, and 7 of these (18%) met criteria for severe CDI. Toxigenic stool cultures were positive for 86% (6/7) of patients with severe CDI, 19% (6/32) of patients with non-severe CDI, and 44% (4/9) of patients who did not meet the clinical case definition of CDI (p = 0.002). Lower tcdB Ct and higher Ept were associated with greater likelihood of toxigenic culture positivity (p = 0.03) and more severe symptoms (p = 0.06). Indeterminate results were not associated with a particular technologist or instrument module, or CD strain type. Conclusions A subset of specimens (1%) using the Xpert® C. difficile assay have typical amplification curves and are interpreted as negative. At least one-third of these results are associated with positive CD culture. The mechanism of these indeterminate results is not technique-related, equipment-related, or due to particular CD strains. Clinicians should be aware that even PCR testing has the potential to miss CDI cases and further highlights the importance of clinical context when interpreting results.
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Affiliation(s)
- Jerome A Leis
- Division of Infectious Diseases, Department of Medicine, University Health Network/Mount Sinai Hospital, Toronto, ON, Canada.
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Bassetti M, Villa G, Pecori D, Arzese A, Wilcox M. Epidemiology, diagnosis and treatment of Clostridium difficile infection. Expert Rev Anti Infect Ther 2013; 10:1405-23. [PMID: 23253319 DOI: 10.1586/eri.12.135] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Clostridium difficile infection (CDI) is considered to be the main cause of bacterial infectious diarrhea in nosocomial settings. Since the beginning of the new century a continuous rise in the incidence of severe CDI has been observed worldwide. Even though some CDI cases are not associated with previous antibiotic exposure, this remains as the principal risk factor for the development of CDI. The rate of recurrences represents perhaps one the most challenging aspect on the management of CDI. There are several microbiological tests available, but glutamate dehydrogenase antigen test can be selected as the first screening step in a diagnostic algorithm, with positive samples then confirmed using a toxin(s) test, to distinguish toxinogenic from nontoxinogenic CDI. Although metronidazole and vancomycin are and have been the mainstay treatment options for CDI, there are some unmet medical and therapeutical needs. Usually oral metronidazole is recommended for initial treatment of nonsevere CDI and vancomycin for treatment of severe disease. Fidaxomicin may be considered in patients who cannot tolerate vancomycin, although more data are needed. For treatment of a nonsevere initial recurrence of CDI, oral metronidazole should be used, but for treatment of subsequent recurrences or more severe cases fidaxomicin may be helpful.
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Affiliation(s)
- Matteo Bassetti
- Infectious Diseases Division, Santa Maria Misericordia University Hospital, Udine, Italy.
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35
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Jin K, Wang S, Huang Z, Lu S. Clostridium difficile infections in China. J Biomed Res 2013; 24:411-6. [PMID: 23554657 PMCID: PMC3596688 DOI: 10.1016/s1674-8301(10)60055-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 10/25/2010] [Accepted: 11/03/2010] [Indexed: 01/05/2023] Open
Abstract
Clostridium difficile (C. difficile) infection has become one of the major hospital-associated infections in Western countries in the last two decades. However, there is limited information on the status of C. difficile infection in Chinese healthcare settings. Given the large and increasing elderly population and the well-recognized problem of over-prescribing of broad spectrum antibiotics in China, it is critical to understand the epidemiology and potential risk factors that may contribute to C. difficile infection in China. A literature review of available published studies, including those in Chinese language-based journals, was conducted. A review of the currently available literature suggested the presence of C. difficile infections in China, but also suggested that these infections were not particularly endemic. This finding should lead to better designed and greatly expanded studies to provide a more reliable epidemiologically-based conclusion on the actual status of C. difficile infection in China, including the identification of any associated risk factors. Such information is ultimately valuable to develop appropriate strategies to prevent C. difficile infection and the vast negative impact of such infections in China and other developing countries.
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Affiliation(s)
- Ke Jin
- Department of Infectious Diseases, ; Jiangsu Province Key Laboratory in Infectious Diseases, ; China-US Vaccine Research Center, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
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Evaluation of the fully automated BD MAX Cdiff and Xpert C. difficile assays for direct detection of Clostridium difficile in stool specimens. J Clin Microbiol 2013; 51:1906-8. [PMID: 23515539 DOI: 10.1128/jcm.00344-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We evaluated the fully automated molecular BD MAX Cdiff assay (BD Diagnostics) and the Xpert C. difficile test (Cepheid) for rapid detection of Clostridium difficile infection. Culture was done on chromogenic agar followed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry identification and toxin detection. Repeat testing was required for 1.8% and 6.0% of the BD MAX and Xpert tests, respectively. Sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) were 90.5%, 97.9%, 89.3%, and 98.1%, respectively, for BD MAX and 97.3%, 97.9%, 90.0%, and 99.5%, respectively, for Xpert.
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37
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Rashid MU, Lozano HM, Weintraub A, Nord CE. In vitro activity of cadazolid against Clostridium difficile strains isolated from primary and recurrent infections in Stockholm, Sweden. Anaerobe 2013; 20:32-5. [PMID: 23454525 DOI: 10.1016/j.anaerobe.2013.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 02/12/2013] [Accepted: 02/19/2013] [Indexed: 02/08/2023]
Abstract
One hundred thirty-three Clostridium difficile strains were collected from 71 patients and analyzed for the presence of C. difficile toxin B by the cell cytotoxicity neutralization assay, genes for toxin A, toxin B, binary toxin and TcdC deletion by PCR. All strains were also PCR-ribotyped and analyzed for sporulation frequency. The MICs of the isolates were determined against cadazolid and seven other antimicrobial agents by the agar dilution method. All isolates were positive for toxin B by the cell cytotoxicity neutralization assay. One hundred fourteen isolates were positive for toxin A and B and 16 isolates were positive for toxin A, toxin B and binary toxin by PCR. Three isolates were negative for toxin A but positive for toxin B. Thirty-three different ribotypes were identified. No strain of ribotype 027 was found. No differences in sporulation were noticed between the primary and recurrent isolates. All 133 isolates were sensitive to cadazolid (0.064-0.5 mg/l), fidaxomicin (0.008-0.125 mg/l), metronidazole (0.125-2 mg/l), vancomycin (0.125-1 mg/l) and tigecycline (0.032-0.25 mg/l). Three isolates were resistant to linezolid (8 mg/l), 15 isolates were resistant to moxifloxacin (8-32 mg/l) and 103 isolates were resistant to clindamycin (8-256 mg/l). No association between toxins A, B and binary toxin, ribotypes or the sporulation and the sensitivity to cadazolid could be found. Cadazolid has a potent in vitro activity against C. difficile.
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Affiliation(s)
- Mamun-Ur Rashid
- Department of Laboratory Medicine, Karolinska University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
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38
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Vehreschild MJGT, Vehreschild JJ, Hübel K, Hentrich M, Schmidt-Hieber M, Christopeit M, Maschmeyer G, Schalk E, Cornely OA, Neumann S. Diagnosis and management of gastrointestinal complications in adult cancer patients: evidence-based guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO). Ann Oncol 2013; 24:1189-202. [PMID: 23401037 DOI: 10.1093/annonc/mdt001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Cancer patients frequently suffer from gastrointestinal complications. However, a comprehensive, practical and evidence-based guideline on this issue is not yet available. PATIENTS AND METHODS An expert group was put together by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO) to develop a guideline on gastrointestinal complications in cancer patients. For each subtopic, a literature search was carried out in PubMed, Medline and Cochrane databases and the strength of recommendation and the quality of the published evidence for major therapeutic strategies were categorized using a modification of the 'Infectious Diseases Society of America' criteria. Consensus discussions were held on each of the topics. RESULTS Recommendations were made with respect to non-infectious and infectious gastrointestinal complications. For all recommendations, the strength of the recommendation and the level of evidence are presented. CONCLUSION This guideline is an evidence-based approach to the diagnosis and management of gastrointestinal complications in cancer patients.
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Abstract
Clostridium difficile is known to cause antibiotic-associated diarrhea and pseudomembranous colitis. Toxinogenic strains of the bacterium produce toxins A (TcdA) and B (TcdB), which are associated with the pathogenicity. The standard methods for diagnosis of C. difficile infection include the cell cytotoxicity assay and the culture of a toxinogenic strain. Due to the long turnaround time of these methods, more rapid methods are preferred. Enzyme immunoassays are fast, but lack sensitivity. Therefore, real-time PCR methods have been developed. The real-time PCR described in this chapter detects tcdB, the gene coding for toxin B. Since toxin A-negative, toxin B-positive strains have been reported to cause disease as well, these strains can also be detected by this method which uses an automated STAR-MagnaPure method for the optimum isolation of DNA from feces. An internal control is included as well to control for inhibition of the PCR method.
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Nassour I, Carchman EH, Simmons RL, Zuckerbraun BS. Novel management strategies in the treatment of severe Clostridium difficile infection. Adv Surg 2012; 46:111-35. [PMID: 22873036 DOI: 10.1016/j.yasu.2012.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
CDI is increasing in incidence and severity. Clinicians must have a low threshold to consider the diagnosis and to treat patients with the clinical syndrome and risk factors before laboratory confirmation of the diagnosis. In patients who have signs of advanced disease, escalation of care with antimicrobial strategies and multidisciplinary care including surgical consultation is necessary. Furthermore, lowering the threshold for surgery compared with traditional approaches likely results in improved survival. Novel surgical approaches may obviate total abdominal colectomy and the associated immediate and long-term morbidity in this often fragile patient population, thus allowing clinicians to embrace surgical therapy earlier in the course of severe, complicated disease.
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Affiliation(s)
- Ibrahim Nassour
- Department of Surgery, University of Pittsburgh, 200 Lothrop Street, F1200 PUH, Pittsburgh, PA 15213, USA
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Shin S, Kim M, Kim M, Lim H, Kim H, Lee K, Chong Y. Evaluation of the Xpert Clostridium difficile assay for the diagnosis of Clostridium difficile infection. Ann Lab Med 2012; 32:355-8. [PMID: 22950071 PMCID: PMC3427823 DOI: 10.3343/alm.2012.32.5.355] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 04/17/2012] [Accepted: 05/25/2012] [Indexed: 12/18/2022] Open
Abstract
Infection with Clostridium difficile is a growing concern because of the increasing prevalence and spread of nosocomial infections. Emergence of the hypervirulent 027/NAP1/BI strain is also notable. Existing diagnostic methods have low sensitivity or are time-consuming. Therefore, establishing a rapid and accurate microbiological diagnostic assay is needed. We evaluated the Xpert C. difficile assay (Xpert CD assay; Cepheid, USA) to detect toxigenic C. difficile. This assay is a real-time multiplex PCR assay that can be used to detect toxigenic C. difficile strains and differentiate the C. difficile presumptive 027/NAP1/BI strain. A total of 253 loose stool specimens were collected and toxigenic cultures, VIDAS C. difficile A & B assays (VIDAS CDAB assay; bioMérieux, France), and the Xpert CD assay were performed. In comparison to toxigenic cultures, the sensitivity, specificity, and positive and negative predictive values were 100%, 94.6%, 83.1%, and 100%, respectively, for the Xpert CD assay and 40.8%, 98.0%, 100%, and 88.9%, respectively, for VIDAS CDAB assay. Because of the low prevalence of the PCR ribotype 027 in Korea, the evaluation of the usefulness of the Xpert CD assay for screening for the 027 strain was limited. The Xpert CD assay provides great sensitivity in diagnosing toxigenic C. difficile infection. In addition, this method has excellent usability because it is simple and fast.
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Affiliation(s)
- Saeam Shin
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
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42
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O'Horo JC, Jones A, Sternke M, Harper C, Safdar N. Molecular techniques for diagnosis of Clostridium difficile infection: systematic review and meta-analysis. Mayo Clin Proc 2012; 87:643-51. [PMID: 22766084 PMCID: PMC3538482 DOI: 10.1016/j.mayocp.2012.02.024] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 02/07/2012] [Accepted: 02/29/2012] [Indexed: 12/16/2022]
Abstract
OBJECTIVE To assess the usefulness of 2 rapid molecular diagnostic techniques, polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP), in Clostridium difficile infection (CDI). METHODS We conducted a systematic review and meta-analysis to evaluate the accuracy of PCR and LAMP in diagnosis of CDI, including studies that used toxigenic culture or cytotoxicity assay as reference standard. RESULTS A search of PubMed and CinAHL medical databases yielded 25 PCR studies, including 11,801 samples that met inclusion criteria and 6 heterogeneous studies that evaluated LAMP. With toxigenic culture as a standard, pooled sensitivity was 0.92 (95% confidence interval [CI], 0.91-0.94); specificity, 0.94 (95% CI, 0.94-0.95); and diagnostic odds ratio, 378 (95% CI, 260-547). With cytotoxicity as a standard, pooled sensitivity was 0.87 (95% CI, 0.84-0.90); specificity, 0.97 (95% CI, 0.97-0.98); and diagnostic odds ratio, 370 (95% CI, 226-606). CONCLUSION Polymerase chain reaction is a highly accurate test for identifying CDI. Heterogeneity in LAMP studies did not allow meta-analysis; however, further research into this promising method is warranted.
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Key Words
- cdi, clostridium difficile infection
- ci, confidence interval
- dor, diagnostic odds ratio
- fn, false-negative
- fp, false-positive
- lamp, loop-mediated isothermal amplification
- lr+, positive likelihood ratio
- lr−, negative likelihood ratio
- npv, negative predictive value
- pcr, polymerase chain reaction
- ppv, positive predictive value
- prisma, preferred reporting items for systematic meta-analysis
- sroc, summary receiver operating curve
- tn, true-negative
- tp, true-positive
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Affiliation(s)
- John C. O'Horo
- Department of Graduate Medical Education, Aurora UW Medical Group, Milwaukee, WI
| | - Amy Jones
- University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Matthew Sternke
- University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Christopher Harper
- University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Nasia Safdar
- William S. Middleton Memorial Veterans Hospital, Madison, WI
- University of Wisconsin School of Medicine and Public Health, Madison, WI
- Section of Infectious Diseases, Department of Medicine, Madison, WI
- Correspondence: Address to Nasia Safdar, MD, PhD, Section of Infectious Diseases, Department of Medicine, MFCB 5221, University of Wisconsin Hospital and Clinics, Madison, WI 53705
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Viala C, Le Monnier A, Maataoui N, Rousseau C, Collignon A, Poilane I. Comparison of commercial molecular assays for toxigenic Clostridium difficile detection in stools: BD GeneOhm Cdiff, XPert C. difficile and illumigene C. difficile. J Microbiol Methods 2012; 90:83-5. [PMID: 22565213 DOI: 10.1016/j.mimet.2012.04.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 04/23/2012] [Accepted: 04/23/2012] [Indexed: 10/28/2022]
Abstract
Three commercial molecular assays were evaluated for toxigenic Clostridium difficile detection in stools. As compared to toxigenic culture, BD GeneOhm Cdiff (BD Diagnostics), XPert C. difficile (Cepheid) and illumigene C. difficile (Meridian Bioscience) demonstrated respectively a sensitivity of 95.5%, 97.8% and 86.7% and a specificity of 97.9%, 97.9% and 100%.
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Affiliation(s)
- Céline Viala
- Laboratoire de Microbiologie, Hôpital Jean Verdier, Assistance Publique - Hôpitaux de Paris, Bondy, France
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44
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Carroll KC, Bartlett JG. Biology of Clostridium difficile: implications for epidemiology and diagnosis. Annu Rev Microbiol 2012; 65:501-21. [PMID: 21682645 DOI: 10.1146/annurev-micro-090110-102824] [Citation(s) in RCA: 172] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Clostridium difficile is an anaerobic, spore-forming, gram-positive rod that causes a spectrum of antibiotic-associated colitis through the elaboration of two large clostridial toxins and other virulence factors. Since its discovery in 1978 as the agent responsible for pseudomembranous colitis, the organism has continued to evolve into an adaptable, aggressive, hypervirulent strain. Advances in molecular methods and improved animal models have facilitated an understanding of how this organism survives in the environment, adapts to the gastrointestinal tract of animals and humans, and accomplishes its unique pathogenesis. The advances in microbiology have been accompanied by some important clinical observations including increased rates of C. difficile infection, increased virulence, and multiple outbreaks. The major new risk is fluoroquinolone use; there is also an association with proton pump inhibitors and increased recognition of cases in outpatients, pediatric patients, and patients without recent antibiotic use. The combination of more aggressive strains with mobile genomes in a setting of an expanded pool of individuals at risk has refocused attention on and challenged assumptions regarding diagnostic gold standards. Future research is likely to build upon the advancements in phylogenetics to create novel strategies for diagnosis, treatment, and prevention.
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Affiliation(s)
- Karen C Carroll
- Division of Medical Microbiology, The Johns Hopkins Medical Institutions, Baltimore, Maryland 21205, USA.
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Rashid MU, Weintraub A, Nord CE. Effect of telavancin on human intestinal microflora. Int J Antimicrob Agents 2011; 38:474-9. [DOI: 10.1016/j.ijantimicag.2011.08.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 08/17/2011] [Accepted: 08/17/2011] [Indexed: 11/25/2022]
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Deshpande A, Pasupuleti V, Rolston DD, Jain A, Deshpande N, Pant C, Hernandez AV. Diagnostic Accuracy of Real-time Polymerase Chain Reaction in Detection of Clostridium difficile in the Stool Samples of Patients With Suspected Clostridium difficile Infection: A Meta-Analysis. Clin Infect Dis 2011; 53:e81-90. [DOI: 10.1093/cid/cir505] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Kim H, Jeong SH, Kim M, Lee Y, Lee K. Detection of Clostridium difficile toxin A/B genes by multiplex real-time PCR for the diagnosis of C. difficile infection. J Med Microbiol 2011; 61:274-277. [PMID: 21959205 DOI: 10.1099/jmm.0.035618-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Toxigenic Clostridium difficile culture is considered to be the standard diagnostic method for the detection of C. difficile infection (CDI). Culture methods are time-consuming and although enzyme immunoassay is rapid and easy to use, it has low sensitivity. In the present study, the AdvanSure CD real-time (RT)-PCR kit (LG Life Sciences) was evaluated for its ability to detect C. difficile toxin A (tcdA) and B (tcdB) genes, simultaneously. A total of 127 fresh diarrhoeal stool specimens, submitted to the clinical microbiology laboratory for C. difficile culture, were tested. C. difficile toxins and toxin genes were detected with a VIDAS C. difficile A&B (VIDAS-CDAB) enzyme-linked fluorescent immunoassay (ELFA) and the AdvanSure RT-PCR kit, respectively, according to the manufacturers' instructions. Their performance was compared with a standard toxigenic culture method as a reference. The sensitivity, specificity and positive and negative predictive values using the AdvanSure RT-PCR kit were 100 %, 98.3 %, 84.6 % and 100 %, respectively, while those of the VIDAS-CDAB system were 63.6 %, 100 %, 100 % and 96.6 %, respectively. Four tcdA(+)/tcdB(+) strains of C. difficile were detected with the AdvanSure RT-PCR kit, which offers comparable sensitivity and specificity to the reference method with a turnaround time of ~3 hours.
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Affiliation(s)
- Heejung Kim
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea
| | - Seok Hoon Jeong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea
| | - Myungsook Kim
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea
| | - Yangsoon Lee
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea
| | - Kyungwon Lee
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea
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Kufelnicka AM, Kirn TJ. Effective utilization of evolving methods for the laboratory diagnosis of Clostridium difficile infection. Clin Infect Dis 2011; 52:1451-7. [PMID: 21628487 DOI: 10.1093/cid/cir201] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Physicians should understand the performance characteristics of evolving laboratory tests used to diagnose Clostridium difficile infection if they are to correctly integrate test results with clinical information and formulate an appropriate therapeutic intervention for patients with antibiotic-associated diarrhea.
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Affiliation(s)
- Anna M Kufelnicka
- Department of Medicine, Division of Infectious Disease, University of Medicine and Dentistry of New Jersey–Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA.
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Tenover FC, Baron EJ, Peterson LR, Persing DH. Laboratory diagnosis of Clostridium difficile infection can molecular amplification methods move us out of uncertainty? J Mol Diagn 2011; 13:573-82. [PMID: 21854871 DOI: 10.1016/j.jmoldx.2011.06.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 05/16/2011] [Accepted: 06/14/2011] [Indexed: 12/18/2022] Open
Abstract
The laboratory diagnosis of Clostridium difficile infection (CDI) continues to be challenging. Recent guidelines from professional societies in the United States note that enzyme immunoassays for toxins A and B do not have adequate sensitivity to be used alone for detecting CDI, yet the optimal method for diagnosing this infection remains unclear. Nucleic acid amplification tests (NAATs) that target chromosomal toxin genes (usually the toxin B gene, tcdB) show high sensitivity and specificity, provide rapid results, and are amenable to both batch and on-demand testing, but these tests were not universally recommended for routine use in the recent guidelines. Rather, two-step algorithms that use glutamate dehydrogenase (GDH) assays to screen for C. difficile in stool specimens, followed by either direct cytotoxin testing or culture to identify toxin-producing C. difficile isolates, were recommended in one guideline and either GDH algorithms or NAATs were recommended in another guideline. Unfortunately, neither culture nor direct cytotoxin testing is widely available. In addition, this two-step approach requires 48 to 92 hours to complete, which may delay the initiation of therapy and critical infection control measures. Recent studies also show the sensitivity of several GDH assays to be <90%. This review considers the role of NAATs for diagnosing CDI and explores their potential advantages over two-step algorithms, including shorter time to results, while providing comparable, if not superior, accuracy.
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Presumptive identification of Clostridium difficile strain 027/NAP1/BI on Cepheid Xpert: interpret with caution. J Clin Microbiol 2011; 49:3719-21. [PMID: 21849697 DOI: 10.1128/jcm.00752-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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