1
|
Mannstadt I, Choy AM, Li J, Green DA, Freedberg DE. Risk factors and clinical outcomes associated with multiple as opposed to single pathogens detected on the gastrointestinal disease polymerase chain reaction assay. Gut Pathog 2024; 16:45. [PMID: 39215373 PMCID: PMC11365154 DOI: 10.1186/s13099-024-00638-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Accepted: 08/22/2024] [Indexed: 09/04/2024] Open
Abstract
BACKGROUND The use of gastrointestinal disease multiplex polymerase chain reaction (GI PCR) testing has become common for suspected gastrointestinal infection. Patients often test positive for multiple pathogens simultaneously through GI PCR, although the clinical significance of this is uncertain. METHODS This retrospective cohort study investigated risk factors and clinical outcomes associated with detection of multiple (as opposed to single) pathogens on GI PCR. We included adult patients who underwent GI PCR testing from 2020 to 2023 and had one or more pathogens detected. We compared patients with multiple versus those with single pathogens and hypothesized that immunosuppression would be a risk factor for detection of multiple pathogens. We further hypothesized that, during the 90 days after GI PCR testing, patients with multiple pathogens would have worse clinical outcomes such as increased rates of emergency department (ED) visits, death, hospitalization, or ambulatory care visits. RESULTS GI PCR was positive in 1341 (29%) of tested patients; 356 patients had multiple pathogens and 985 had one pathogen. The most common pathogens included Enteropathogenic Escherichia coli (EPEC, 27%), norovirus (17%), and Enteroaggregative E. coli (EAEC, 14%) in both multi- and singly positive patients. Immunosuppression was not associated with multiple pathogens (adjusted odds ratio [aOR] 1.35, 95% CI 0.96, 1.86). The factors most associated with multiple pathogens were Hispanic ethnicity (OR 1.86, 95% CI 1.42, 2.45) and chronic kidney disease (OR 1.69, 95% CI 1.13, 2.49). Patients with multiple pathogens were more likely to have ED visits during the 90 days after GI PCR testing (40% vs. 32%, p < 0.01), but they were not more likely to die, be hospitalized, or to have ambulatory medical visits. CONCLUSIONS Immunosuppression was not associated with detection of multiple as opposed to single pathogens on GI PCR testing. There were worse clinical outcomes associated with detection of multiple pathogens, although these effects were modest.
Collapse
Affiliation(s)
- Insa Mannstadt
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
| | - Alexa M Choy
- Division of Digestive and Liver Diseases, Columbia University Irving Medical Center-New York Presbyterian Hospital, New York, NY, USA
| | - Jianhua Li
- Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Daniel A Green
- Clinical Microbiology, Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Daniel E Freedberg
- Division of Digestive and Liver Diseases, Columbia University Irving Medical Center-New York Presbyterian Hospital, New York, NY, USA
| |
Collapse
|
2
|
Agudelo-Pérez S, Moreno AM, Martínez-Garro J, Salazar J, Lopez R, Perdigón M, Peláez R. 16S rDNA Sequencing for Bacterial Identification in Preterm Infants with Suspected Early-Onset Neonatal Sepsis. Trop Med Infect Dis 2024; 9:152. [PMID: 39058194 PMCID: PMC11281265 DOI: 10.3390/tropicalmed9070152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 06/18/2024] [Accepted: 06/26/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND The high prevalence of suspected early-onset neonatal sepsis among preterm infants leads to immediate antibiotic administration upon admission. Notably, most blood cultures for suspected early-onset neonatal sepsis do not yield a causative pathogen. This study aimed to assess polymerase chain reaction (PCR) targeting the variable region V4 of the 16S ribosomal gene (16S rDNA) and Sanger sequencing for bacterial identification in preterm infants with suspected early-onset neonatal sepsis. METHODS Therefore, this prospective study was conducted. Preterm infants with suspected early-onset neonatal sepsis were included in this study. The three groups were formed based on the risk of infection and clinical sepsis. Blood samples were collected upon admission to the neonatal unit for culture and molecular analysis. PCR amplification and subsequent Sanger sequencing of the V4 region of the 16S rDNA were performed. RESULTS Twenty-eight patients were included in this study. Blood cultures were negative in 100% of the patients. Amplification and sequencing of the V4 region identified bacterial genera in 19 patients across distinct groups. The predominant taxonomically identified genus was Pseudomonas. CONCLUSIONS Amplifying the 16S rDNA variable region through PCR and subsequent Sanger sequencing in preterm neonates with suspected early-onset neonatal sepsis can enhance the identification of microbial species that cause infection, especially in negative cultures.
Collapse
Affiliation(s)
- Sergio Agudelo-Pérez
- Department of Pediatrics, Faculty of Medicine, Universidad de La Sabana, Chía 025001, Colombia;
| | - A. Melissa Moreno
- Faculty of Science and Biotechnology, Universidad CES, Medellin 050022, Colombia; (A.M.M.); (J.M.-G.)
| | - Juliana Martínez-Garro
- Faculty of Science and Biotechnology, Universidad CES, Medellin 050022, Colombia; (A.M.M.); (J.M.-G.)
| | - Jorge Salazar
- Research Center, Grupo de Estudio de Enfermedades Infecciosas y Crónicas (GEINCRO), San Martin University Foundation, Sabaneta 055450, Colombia;
| | - Ruth Lopez
- Neonatal Unit, Hospital Meissen, Bogotá 111711, Colombia;
| | - Mateo Perdigón
- Department of Pediatrics, Faculty of Medicine, Universidad de La Sabana, Chía 025001, Colombia;
| | - Ronald Peláez
- Graduate School, Universidad CES, Medellin 050022, Colombia;
| |
Collapse
|
3
|
Schawaller M, Wiemer D, Hagen RM, Frickmann H. Infectious diseases in German military personnel after predominantly tropical deployments: a retrospective assessment over 13 years. BMJ Mil Health 2023; 169:146-151. [PMID: 33257519 DOI: 10.1136/bmjmilitary-2020-001575] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 11/11/2020] [Accepted: 11/15/2020] [Indexed: 12/18/2022]
Abstract
OBJECTIVES Military deployments to the tropics are associated with specific infection risks. To add to the available epidemiological information, infectious disease risks in German military personnel returning from predominantly tropical deployments were assessed. METHODS Since 2006, German soldiers returning from predominantly tropical deployments have been offered the opportunity of returnee screenings at the Department of Tropical Medicine and Infectious Diseases of the Bundeswehr Hospital Hamburg. Case files and diagnostic results recorded between 2006 and 2018 were retrospectively assessed to identify deployment-associated infectious disease risks. RESULTS Along with high enteric colonisation rates with apathogenic protozoa and resistant Enterobacteriaceae, direct or indirect proof of infections among the 764 assessed cases comprised Plasmodium spp (n=37), Giardia duodenalis (n=21), Schistosoma spp (n=14), Yersinia enterocolitica (n=5), Strongyloides stercoralis (n=3), Campylobacter jejuni (n=1), Leishmania spp (n=1) and Salmonella enterica (n=1), as well as latent infections with Mycobacterium tuberculosis complex (n=8). The infections were mainly imported from the African region and Eastern Mediterranean region and high proportions of cases lacked typical symptoms. Reported side effect rates of antimalarial chemoprophylaxis for mefloquine (n=121), atovaquone/proguanil (n=49) and doxycycline (n=6) were 36.3%, 19.3% and 11.8%, respectively, while non-compliance rates were 12.9%, 13.0% and 5.9%, respectively. CONCLUSIONS Considerable rates of infections with sometimes atypical or absent symptoms confirm a need for returnee screenings after tropical deployments. High reported side effect rates for mefloquine support its replacement by atovaquone/proguanil or doxycycline for antimalarial chemoprophylaxis.
Collapse
Affiliation(s)
- Marius Schawaller
- Department of Tropical Medicine and Infectious Diseases, Bundeswehrkrankenhaus Hamburg, Hamburg, Germany
| | - D Wiemer
- Department of Tropical Medicine and Infectious Diseases, Bundeswehrkrankenhaus Hamburg, Hamburg, Germany
| | - R M Hagen
- Department of Microbiology and Hospital Hygiene, Bundeswehrzentralkrankenhaus Koblenz, Koblenz, Germany
| | - H Frickmann
- Department of Microbiology and Hospital Hygiene, Bundeswehrkrankenhaus Hamburg, Hamburg, Germany
- Institute for Medical Microbiology, Virology and Hygiene, Universitätsmedizin Rostock, Rostock, Germany
| |
Collapse
|
4
|
Kann S, Eberhardt K, Hinz R, Schwarz NG, Dib JC, Aristizabal A, Mendoza GAC, Hagen RM, Frickmann H, Barrantes I, Kreikemeyer B. The Gut Microbiome of an Indigenous Agropastoralist Population in a Remote Area of Colombia with High Rates of Gastrointestinal Infections and Dysbiosis. Microorganisms 2023; 11:625. [PMID: 36985199 PMCID: PMC10052337 DOI: 10.3390/microorganisms11030625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/20/2023] [Accepted: 02/21/2023] [Indexed: 03/05/2023] Open
Abstract
An Indigenous agropastoralist population called the Wiwa from the Sierra Nevada de Santa Marta, in North-East Colombia, shows high rates of gastrointestinal infections. Chronic gut inflammatory processes and dysbiosis could be a reason, suggesting an influence or predisposing potential of the gut microbiome composition. The latter was analyzed by 16S rRNA gene amplicon next generation sequencing from stool samples. Results of the Wiwa population microbiomes were associated with available epidemiological and morphometric data and compared to control samples from a local urban population. Indeed, locational-, age-, and gender-specific differences in the Firmicutes/Bacteriodetes ratio, core microbiome, and overall genera-level microbiome composition were shown. Alpha- and ß-diversity separated the urban site from the Indigenous locations. Urban microbiomes were dominated by Bacteriodetes, whereas Indigenous samples revealed a four times higher abundance of Proteobacteria. Even differences among the two Indigenous villages were noted. PICRUSt analysis identified several enriched location-specific bacterial pathways. Moreover, on a general comparative scale and with a high predictive accuracy, we found Sutterella associated with the abundance of enterohemorrhagic Escherichia coli (EHEC), Faecalibacteria associated with enteropathogenic Escherichia coli (EPEC) and helminth species Hymenolepsis nana and Enterobius vermicularis. Parabacteroides, Prevotella, and Butyrivibrio are enriched in cases of salmonellosis, EPEC, and helminth infections. Presence of Dialister was associated with gastrointestinal symptoms, whereas Clostridia were exclusively found in children under the age of 5 years. Odoribacter and Parabacteroides were exclusively identified in the microbiomes of the urban population of Valledupar. In summary, dysbiotic alterations in the gut microbiome in the Indigenous population with frequent episodes of self-reported gastrointestinal infections were confirmed with epidemiological and pathogen-specific associations. Our data provide strong hints of microbiome alterations associated with the clinical conditions of the Indigenous population.
Collapse
Affiliation(s)
- Simone Kann
- Department for Research and Development, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany
| | - Kirsten Eberhardt
- Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
- Division of Hygiene and Infectious Diseases, Institute of Hygiene and Environment, 20539 Hamburg, Germany
| | - Rebecca Hinz
- SYNLAB Medizinisches Versorgungszentrum Hamburg GmbH, 22083 Hamburg, Germany
| | | | - Juan Carlos Dib
- Department of Medicine, Fundación Universidad de Norte, Baranquilla 080001, Colombia
| | | | | | - Ralf Matthias Hagen
- Department of Microbiology and Hospital Hygiene, Bundeswehr Central Hospital Koblenz, 56070 Koblenz, Germany
| | - Hagen Frickmann
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany
| | - Israel Barrantes
- Research Group Translational Bioinformatics, Institute for Biostatistics and Informatics in Medicine und Aging Research, University Medicine Rostock, 18057 Rostock, Germany
| | - Bernd Kreikemeyer
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany
| |
Collapse
|
5
|
Kann S, Concha G, Köller T, Alker J, Schotte U, Hahn A, Frickmann H, Warnke P. Enteric Bacteria and Parasites with Pathogenic Potential in Individuals of the Colombian Indigenous Tribe Kogui. Microorganisms 2022; 10:microorganisms10091862. [PMID: 36144464 PMCID: PMC9500837 DOI: 10.3390/microorganisms10091862] [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: 08/18/2022] [Revised: 09/03/2022] [Accepted: 09/15/2022] [Indexed: 11/16/2022] Open
Abstract
The Kogui tribe is an indigenous population living in Colombia. The prevalence values of some enteric bacteria, parasites and microsporidia in Kogui stool samples (n = 192) were assessed by real-time polymerase chain reaction (PCR). Thus, genus- or species-specifically recorded positivity rates among the Kogui community were assessed. Protozoa were the leading microorganisms in the stool samples of the Kogui, with an average of 1.5 pathogens per sample, followed by bacteria, with 0.6 pathogens per samples and helminths, with 0.3 pathogens per sample. Microsporidia were not detected. Thereby, the majority of detected protozoa comprised species with questionable etiological relevance such as Blastocystis hominis (n = 173) and Dientamoeba fragilis (n = 44), but also a considerable proportion of Giardia duodenalis (n = 71). Cryptosporidium spp., in contrast, was found in a single instance only. The majority of recorded bacteria were Campylobacter spp., with a strikingly high proportion of 50% (n = 96), followed by Shigella spp./enteroinvasive E. coli (EIEC) (n = 14) and Aeromonas spp. (n = 4). The quantitatively most important detected helminths were Ascaris spp. (n = 15), Hymenolepis spp. (n = 14) and Trichuris trichiura (n = 12), followed by Necator americanus (n = 6), Taenia spp. (n = 3) and Strongyloides stercoralis (n = 3) in descending order of abundance. As expected, the Kogui people's living conditions comprising poverty, lack of access to clean water and simple housing favor a high number of gastrointestinal infections. Preventive approaches are needed to reduce their risk of infection.
Collapse
Affiliation(s)
- Simone Kann
- Missionsärztliches Institut, 97074 Würzburg, Germany
- Correspondence: (S.K.); (P.W.)
| | - Gustavo Concha
- Organization Wiwa Yugumaiun Bunkauanarrua Tayrona (OWYBT), Department Health Advocacy, Valledupar 2000001, Colombia
| | - Thomas Köller
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany
| | - Juliane Alker
- Department A-Veterinary Medicine, Central Institute of the Bundeswehr Medical Service Kiel, 24119 Kronshagen, Germany
| | - Ulrich Schotte
- Department A-Veterinary Medicine, Central Institute of the Bundeswehr Medical Service Kiel, 24119 Kronshagen, 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
| | - Philipp Warnke
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany
- Correspondence: (S.K.); (P.W.)
| |
Collapse
|
6
|
Truong J, Cointe A, Le Roux E, Bidet P, Michel M, Boize J, Mariani-Kurkdjian P, Caseris M, Hobson CA, Desmarest M, Titomanlio L, Faye A, Bonacorsi S. Clinical impact of a gastrointestinal PCR panel in children with infectious diarrhoea. Arch Dis Child 2022; 107:601-605. [PMID: 34921002 DOI: 10.1136/archdischild-2021-322465] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 11/28/2021] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Multiplex gastrointestinal PCR (GI-PCR) allows fast and simultaneous detection of 22 enteric pathogens (including Campylobacter, Salmonella, Shigella/enteroinvasive Escherichia coli (EIEC), among other bacteria, parasites and viruses). However, its impact on the management of children with infectious diarrhoea remains unknown. PATIENTS/DESIGN All children eligible for stool culture from May to October 2018 were prospectively included in a monocentric study at Robert-Debré University-Hospital. INTERVENTION A GI-PCR (BioFire FilmArray) was performed on each stool sample. MAIN MEASURES Data on the children's healthcare management before and after GI-PCR results were collected. Stool culture results were also reported. RESULTS 172 children were included. The main criteria for performing stool analysis were mucous/bloody diarrhoea and/or traveller's diarrhoea (n=130). GI-PCR's were positive for 120 patients (70%). The main pathogens were enteroaggregative E. coli (n=39; 23%), enteropathogenic E. coli (n=34; 20%), Shigella/EIEC (n=27; 16%) and Campylobacter (n=21; 12%). Compared with stool cultures, GI-PCR enabled the detection of 21 vs 19 Campylobacter, 12 vs 10 Salmonella, 27 Shigella/EIEC vs 13 Shigella, 2 vs 2 Yersinia enterocolitica, 1 vs 1 Plesiomonas shigelloides, respectively. Considering the GI-PCR results and before stool culture results, the medical management was revised for 40 patients (23%): 28 initiations, 2 changes and 1 discontinuation of antibiotics, 1 hospitalisation, 2 specific room isolations related to Clostridioides difficile infections, 4 additional test prescriptions and 2 test cancellations. CONCLUSION The GI-PCR's results impacted the medical management of gastroenteritis for almostone-fourth of the children, and especially the prescription of appropriate antibiotic treatment before stool culture results.
Collapse
Affiliation(s)
- Jeanne Truong
- General Paediatrics, Robert Debré University Hospital, AP-HP, Paris, France .,Université de Paris, UFR de médecine Paris-Nord, Paris, Île-de-France, France
| | - Aurélie Cointe
- Microbiology Laboratory, Robert-Debré University Hospital, AP-HP, Paris, Île-de-France, France.,IAME UMR 1137, INSERM, Paris, Île-de-France, France
| | - Enora Le Roux
- Unité d'Epidémiologie Clinique, Robert Debré University Hospital, AP-HP, Paris, France.,ECEVE UMR-1123, INSERM, Paris, Île-de-France, France
| | - Philippe Bidet
- Microbiology Laboratory, Robert-Debré University Hospital, AP-HP, Paris, Île-de-France, France.,IAME UMR 1137, INSERM, Paris, Île-de-France, France
| | - Morgane Michel
- ECEVE UMR-1123, INSERM, Paris, Île-de-France, France.,URC Eco, Hôtel-Dieu, AP-HP, Paris, France
| | - Julien Boize
- Department of Paediatric Emergency Care, Robert Debré University Hospital, AP-HP, Paris, Île-de-France, France
| | | | - Marion Caseris
- General Paediatrics, Robert Debré University Hospital, AP-HP, Paris, France
| | - Claire Amaris Hobson
- Université de Paris, UFR de médecine Paris-Nord, Paris, Île-de-France, France.,IAME UMR 1137, INSERM, Paris, Île-de-France, France
| | - Marie Desmarest
- Department of Paediatric Emergency Care, Robert Debré University Hospital, AP-HP, Paris, Île-de-France, France
| | - Luigi Titomanlio
- Université de Paris, UFR de médecine Paris-Nord, Paris, Île-de-France, France.,Department of Paediatric Emergency Care, Robert Debré University Hospital, AP-HP, Paris, Île-de-France, France.,U1141, INSERM, Paris, France
| | - Albert Faye
- General Paediatrics, Robert Debré University Hospital, AP-HP, Paris, France.,Université de Paris, UFR de médecine Paris-Nord, Paris, Île-de-France, France.,ECEVE UMR-1123, INSERM, Paris, Île-de-France, France
| | - Stéphane Bonacorsi
- Microbiology Laboratory, Robert-Debré University Hospital, AP-HP, Paris, Île-de-France, France.,IAME UMR 1137, INSERM, Paris, Île-de-France, France
| |
Collapse
|
7
|
Yang J, Li D, Wang J, Zhang R, Li J. Design, optimization, and application of multiplex rRT-PCR in the detection of respiratory viruses. Crit Rev Clin Lab Sci 2022:1-18. [PMID: 35559711 DOI: 10.1080/10408363.2022.2072467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Viral respiratory infections are common and serious diseases. Because there is no effective treatment method or vaccine for respiratory tract infection, early diagnosis is vital to identify the pathogen so as to determine the infectivity of the patient and to quickly take measures to curb the spread of the virus, if warranted, to avoid serious public health problems. Real-time reverse transcriptase PCR (rRT-PCR), which has high sensitivity and specificity, is the best approach for early diagnosis. Among rRT-PCR methods, multiplex rRT-PCR can resolve issues arising from various types of viruses, high mutation frequency, coinfection, and low concentrations of virus. However, the design, optimization, and validation of multiplex rRT-PCR are more complicated than singleplex rRT-PCR, and comprehensive research on multiplex rRT-PCR methodology is lacking. This review summarizes recent progress in multiplex rRT-PCR methodology, outlines the principles of design, optimization and validation, and describes a scheme to help diagnostic companies to design and optimize their multiplex rRT-PCR detection panel and to assist laboratory staff to solve problems in their daily work. In addition, the analytical validity, clinical validity and clinical utility of multiplex rRT-PCR in viral respiratory tract infection diagnosis are assessed to provide theoretical guidance and useful information for physicians to understand the test results.
Collapse
Affiliation(s)
- Jing Yang
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, P.R. China.,Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P.R. China.,Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, P.R. China
| | - Dandan Li
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, P.R. China.,Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P.R. China.,Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, P.R. China
| | - Jie Wang
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, P.R. China.,Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P.R. China.,Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, P.R. China
| | - Rui Zhang
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, P.R. China.,Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P.R. China.,Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, P.R. China
| | - Jinming Li
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, P.R. China.,Graduate School of Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P.R. China.,Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, P.R. China
| |
Collapse
|
8
|
Multicentric Evaluation of SeeGene Allplex Real-Time PCR Assays Targeting 28 Bacterial, Microsporidal and Parasitic Nucleic Acid Sequences in Human Stool Samples. Diagnostics (Basel) 2022; 12:diagnostics12041007. [PMID: 35454056 PMCID: PMC9032746 DOI: 10.3390/diagnostics12041007] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/13/2022] [Accepted: 04/15/2022] [Indexed: 12/10/2022] Open
Abstract
Prior to the implementation of new diagnostic techniques, a thorough evaluation is mandatory in order to ensure diagnostic reliability. If positive samples are scarcely available, however, such evaluations can be difficult to perform. Here, we evaluated four SeeGene Allplex real-time PCR assays amplifying a total of 28 bacteria, microsporidal and parasitic nucleic acid sequence targets in human stool samples in a multicentric approach. In the assessments with strongly positive samples, sensitivity values ranging between 13% and 100% were recorded for bacteria, between 0% and 100% for protozoa and between 7% and 100% for helminths and microsporidia; for the weakly positive samples, the recorded sensitivity values for bacteria ranged from 0% to 100%; for protozoa, from 0% to 40%; and for helminths and microsporidia, from 0% to 53%. For bacteria, the recorded specificity was in the range between 87% and 100%, while a specificity of 100% was recorded for all assessed PCRs targeting parasites and microsporidia. The intra- and inter-assay variations were generally low. Specifically for some helminth species, the sensitivity could be drastically increased by applying manual nucleic acid extraction instead of the manufacturer-recommended automatic procedure, while such effects were less obvious for the bacteria and protozoa. In summary, the testing with the chosen positive control samples showed varying degrees of discordance between the evaluated Allplex assays and the applied in-house reference assays associated with higher cycle threshold values in the Allplex assays, suggesting that samples with very low pathogen densities might be missed. As the targeted species can occur as harmless colonizers in the gut of individuals in high-endemicity settings as well, future studies should aim at assessing the clinical relevance of the latter hint.
Collapse
|
9
|
Kann S, Concha G, Hartmann M, Köller T, Alker J, Schotte U, Kreienbrock L, Frickmann H, Warnke P. Only Low Effects of Water Filters on the Enteric Carriage of Gastrointestinal Pathogen DNA in Colombian Indigenous People. Microorganisms 2022; 10:microorganisms10030658. [PMID: 35336233 PMCID: PMC8955181 DOI: 10.3390/microorganisms10030658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/28/2022] [Accepted: 03/17/2022] [Indexed: 12/18/2022] Open
Abstract
Water filtration is a common strategy of water sanitation in resource-poor tropical settings. Here, we assessed the intermediate term effect of this preventive procedure including specific filter-related as well as general hygiene training on the molecular detection of enteric pathogens in stool samples from Colombian Indigenous people. From a total of 89 individuals from an Indigenous tribe called Wiwa, stool samples were assessed by real-time PCR for enteropathogenic microorganisms prior to the implementation of water filtration-based infection prevention. Three years after the onset of the preventive strategy, a follow-up assessment was performed. A significantly beneficial effect of water filtration could be shown for Ascaris spp. only (p = 0.035) and a tendency (p = 0.059) for Hymenolepis nana. No hints for effects on the gastrointestinal shedding of Giardia duodenalis, Entamoeba histolytica, Cryptosporidium spp., Campylobacter spp., Shigella spp./enteroinvasive Escherichia coli, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, and Taenia spp. were seen. In conclusion, the study indicates that water filtration can only be an element of a multi-modal hygiene concept to reduce enteric pathogen carriage in inhabitants of resource-poor tropical settings in spite of tendencies of beneficial effects.
Collapse
Affiliation(s)
- Simone Kann
- Medical Mission Institute, 97074 Würzburg, Germany
- Correspondence: (S.K.); (P.W.)
| | - Gustavo Concha
- Organization Wiwa Yugumaiun Bunkauanarrua Tayrona (OWYBT), Department Health Advocacy, Valledupar 2000001, Colombia;
| | - Maria Hartmann
- Institute for Biometry, Epidemiology and Information Processing, Veterinary Medical University Hannover, 30559 Hannover, Germany; (M.H.); (L.K.)
| | - Thomas Köller
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany; (T.K.); (H.F.)
| | - Juliane Alker
- Department A-Veterinary Medicine, Central Institute of the Bundeswehr Medical Service Kiel, 24119 Kronshagen, Germany; (J.A.); (U.S.)
| | - Ulrich Schotte
- Department A-Veterinary Medicine, Central Institute of the Bundeswehr Medical Service Kiel, 24119 Kronshagen, Germany; (J.A.); (U.S.)
| | - Lothar Kreienbrock
- Institute for Biometry, Epidemiology and Information Processing, Veterinary Medical University Hannover, 30559 Hannover, Germany; (M.H.); (L.K.)
| | - Hagen Frickmann
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany; (T.K.); (H.F.)
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany
| | - Philipp Warnke
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany
- Correspondence: (S.K.); (P.W.)
| |
Collapse
|
10
|
Comparison of Three Real-Time PCR Assays Targeting the SSU rRNA Gene, the COWP Gene and the DnaJ-Like Protein Gene for the Diagnosis of Cryptosporidium spp. in Stool Samples. Pathogens 2021; 10:pathogens10091131. [PMID: 34578163 PMCID: PMC8472038 DOI: 10.3390/pathogens10091131] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 08/29/2021] [Accepted: 09/02/2021] [Indexed: 02/07/2023] Open
Abstract
As qualified microscopy of enteric parasitoses as defined by high diagnostic accuracy is difficult to maintain in non-endemic areas due to scarce opportunities for practicing with positive sample materials, molecular diagnostic options provide less investigator-dependent alternatives. Here, we compared three molecular targets for the real-time PCR-based detection of Cryptosporidium spp. From a population of 1000 individuals comprising both Ghanaian HIV (human immunodeficiency virus) patients and military returnees after deployment in the tropics, stool samples were assessed for Cryptosporidium spp. by real-time PCR targeting the small subunit ribosomal RNA (SSU rRNA) gene, the Cryptosporidium oocyst wall (COWP) gene, and the DnaJ-like protein gene (DnaJ), respectively. In declining order, sensitivity of 100% for the SSU rRNA gene PCR, 90.0% for the COWP PCR and 88.8% for the DnaJ PCR, respectively, as well as specificity of 99.6% for the COWP PCR and 96.9% for both the SSU rRNA gene PCR and the DnaJ PCR, respectively, were recorded. Substantial agreement (kappa value 0.663) between the three assays was observed. Further, an accuracy-adjusted Cryptosporidium spp. prevalence of 6.0% was calculated for the study population. In conclusion, none of the assessed real-time PCR assays were associated with perfect test accuracy. However, a combination of highly sensitive SSU rRNA gene PCR for screening purposes and more specific COWP PCR for confirmatory testing should allow reliable diagnosis of Cryptosporidium spp. in stool samples even in low prevalence settings.
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
Schotte U, Hoffmann T, Schwarz NG, Rojak S, Lusingu J, Minja D, Kaseka J, Mbwana J, Gesase S, May J, Dekker D, Frickmann H. Study of enteric pathogens among children in the tropics and effects of prolonged storage of stool samples. Lett Appl Microbiol 2021; 72:774-782. [PMID: 33544912 DOI: 10.1111/lam.13457] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/13/2021] [Accepted: 01/28/2021] [Indexed: 12/11/2022]
Abstract
The study was performed to compare real-time PCR after nucleic acid extraction directly from stool samples as well as from samples stored and transported on Whatman papers or flocked swabs at ambient temperature in the tropics. In addition, the possible suitability for a clear determination of likely aetiological relevance of PCR-based pathogen detections based on cycle threshold (Ct) values was assessed. From 632 Tanzanian children <5 years of age with and without gastrointestinal symptoms, 466 samples were subjected to nucleic acid extraction and real-time PCR for gastrointestinal viral, bacterial and protozoan pathogens. Equal or even higher frequencies of pathogen detections from Whatman papers or flocked swabs were achieved compared with nucleic acid extraction directly from stool samples. Comparison of the Ct values showed no significant difference according to the nucleic acid extraction strategy. Also, the Ct values did not allow a decision whether a detected pathogen was associated with gastrointestinal symptoms.
Collapse
Affiliation(s)
- U Schotte
- Department A - Veterinary Medicine, Central Institute of the Bundeswehr Medical Service Kiel, Kronshagen, Germany
| | - T Hoffmann
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | - N G Schwarz
- Infectious Disease Epidemiology Department, Bernhard Nocht Institute for Tropical Medicine Hamburg, Hamburg, Germany
| | - S Rojak
- Department of Microbiology and Hospital Hygiene, Bundeswehr Central Hospital Koblenz, Koblenz, Germany
| | - J Lusingu
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - D Minja
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - J Kaseka
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - J Mbwana
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - S Gesase
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - J May
- Infectious Disease Epidemiology Department, Bernhard Nocht Institute for Tropical Medicine Hamburg, Hamburg, Germany
| | - D Dekker
- Infectious Disease Epidemiology Department, Bernhard Nocht Institute for Tropical Medicine Hamburg, Hamburg, Germany
| | - H Frickmann
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany.,Department of Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| |
Collapse
|
13
|
Frickmann H, Alker J, Hansen J, Dib JC, Aristizabal A, Concha G, Schotte U, Kann S. Seasonal Differences in Cyclospora cayetanensis Prevalence in Colombian Indigenous People. Microorganisms 2021; 9:microorganisms9030627. [PMID: 33803496 PMCID: PMC8002917 DOI: 10.3390/microorganisms9030627] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 12/15/2022] Open
Abstract
Fecal-orally transmitted cyclosporiasis is frequent in remote resource-limited settings in Central and South America with poor hygiene conditions. In this study, we aimed at assessing seasonal effects on the epidemiology of colonization or infection with C. cayetanensis in Colombian indigenous people living under very restricted conditions. In the rainy season between July and November and in the dry season between January and April, stool samples from indigenous people with and without gastrointestinal symptoms were collected and screened for C. cayetanensis applying in-house real-time polymerase chain reaction (PCR). In the rainy season and in the dry season, positive PCR results were observed for 11.8% (16/136) and 5.1% (15/292), respectively, with cycle threshold (Ct) values of 30.6 (±3.4) and 34.4 (±1.6), respectively. Despite higher parasite loads in the rainy season, fewer individuals (2/16, 12.5%) reported gastrointestinal symptoms compared to the dry season (6/15, 40%). In conclusion, considerable prevalence of C. cayetanensis in Colombian indigenous people persists in the dry season. Low proportions of gastrointestinal symptoms along with higher parasite loads make colonization likely rather than infection.
Collapse
Affiliation(s)
- Hagen Frickmann
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany;
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany
| | - Juliane Alker
- Central Institute of the Bundeswehr Medical Service Kiel, Department A—Veterinary Medicine, 24119 Kronshagen, Germany; (J.A.); (U.S.)
| | - Jessica Hansen
- Department for Infectious Disease Diagnostics, Bernhard-Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany;
| | - Juan Carlos Dib
- Tropical Health Foundation, Santa Marta 470003, Colombia; (J.C.D.); (A.A.)
| | - Andrés Aristizabal
- Tropical Health Foundation, Santa Marta 470003, Colombia; (J.C.D.); (A.A.)
| | - Gustavo Concha
- Organization Wiwa Yugumaiun Bunkauanarrua Tayrona (OWYBT), Department Health Advocacy, Valledupar 200001, Colombia;
| | - Ulrich Schotte
- Central Institute of the Bundeswehr Medical Service Kiel, Department A—Veterinary Medicine, 24119 Kronshagen, Germany; (J.A.); (U.S.)
| | - Simone Kann
- Medical Mission Institute, 97074 Würzburg, Germany
- Correspondence: ; Tel.: +49-931-8048521; Fax: +49-931-8048525
| |
Collapse
|
14
|
Tisdale MD, Mitra I, McCoy AJ, Simons MP, Reynolds ND, Swierczewski BE, Liu J, Houpt ER, Fraser JA, Riddle MS, Tribble DR, Lalani T. Performance characteristics of a quantitative PCR assay on repository stool specimens and smeared filter-paper cards. BMC Res Notes 2020; 13:500. [PMID: 33126904 PMCID: PMC7597010 DOI: 10.1186/s13104-020-05340-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 10/14/2020] [Indexed: 12/30/2022] Open
Abstract
Objective Stool repositories are a valuable resource for retrospective analyses including quantitative PCR assays to distinguish between asymptomatic shedding and clinical disease. The suitability of archival specimens for this purpose is unclear and requires assessment. We conducted a pilot study to evaluate pathogen detection by TaqMan Array Card (TAC) in travelers’ diarrhea (TD) stool specimens stored for 1–13 years, as well as the impact of transporting specimens on Whatman FTA Elute cards (FTA Cards) on detection. Results The positive percent agreement (PPA) for TAC on stool vs. microbiologic testing was lower than our a priori PPA estimate of 80% for most pathogens: Shigella spp. (100% [95%CI 69–100%]), enterotoxigenic E coli (ETEC) (63% [95%CI 49–75%]), Campylobacter spp. (66% [95%CI 43–85%]) and Norovirus (37% [95%CI 16–61%]). Use of the FTA card resulted in a further reduction of PPA. Our findings suggest that archival specimens may lead to insensitive detection on quantitative PCR assays due to degradation of nucleic acid with prolonged storage, although our limited sample size precluded us from evaluating the impact of storage duration on nucleic acid yield. Additional studies are needed to understand the impact of storage duration on quantitative PCR data.
Collapse
Affiliation(s)
- Michele D Tisdale
- Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA. .,Naval Medical Center Portsmouth, Portsmouth, VA, USA. .,The Henry M Jackson Foundation for the Advancement of Military Medicine, Inc, Bethesda, MD, USA. .,Infectious Disease & Travel Clinic, Building 3, 1st Floor, Naval Medical Center Portsmouth, Portsmouth, VA, 23708, USA.
| | - Indrani Mitra
- Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.,The Henry M Jackson Foundation for the Advancement of Military Medicine, Inc, Bethesda, MD, USA
| | | | | | | | | | - Jie Liu
- University of Virginia, Charlottesville, VA, USA
| | - Eric R Houpt
- University of Virginia, Charlottesville, VA, USA
| | - Jamie A Fraser
- Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.,The Henry M Jackson Foundation for the Advancement of Military Medicine, Inc, Bethesda, MD, USA
| | - Mark S Riddle
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - David R Tribble
- Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Tahaniyat Lalani
- Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.,Naval Medical Center Portsmouth, Portsmouth, VA, USA.,The Henry M Jackson Foundation for the Advancement of Military Medicine, Inc, Bethesda, MD, USA
| |
Collapse
|
15
|
Halfter M, Müseler U, Hagen RM, Frickmann H. Enteric pathogens in German police officers after predominantly tropical deployments - A retrospective assessment over 5 years. Eur J Microbiol Immunol (Bp) 2020; 10:172-177. [PMID: 33021951 PMCID: PMC7592512 DOI: 10.1556/1886.2020.00026] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 09/04/2020] [Indexed: 11/19/2022] Open
Abstract
Introduction The study was performed to assess the infection risk of German police officers on predominantly tropical deployments, mostly United Nations missions, with gastrointestinal pathogens. Methods Police officers were offered PCR-based screening for gastrointestinal pathogens before and after deployment. The screening panel comprised enteroinvasive bacteria (Salmonella spp., Shigella spp./enteroinvasive Escherichia coli, Campylobacter jejuni, and Yersinia spp.), enteropathogenic protozoa (Entamoeba histolytica, Giardia duodenalis, Cryptosporidium spp., and Cyclospora cayetanensis), as well as enteric helminths (Ancyclostoma spp., Ascaris lumbricoides, Enterobius vermicularis, Hymenolepis nana, Necator americanus, African Schistosoma spp., Strongyloides stercoralis, Taenia saginata, Taenia solium, and Trichuris trichiura). Results G. duodenalis (n = 3), C. jejuni (n = 2), Salmonella spp. (n = 1), Shigella spp./enteroinvasive E. coli (n = 3), and S. stercoralis (n = 3) were detect in 12 out of 133 (9.0%) police officers. The majority had shown gastrointestinal symptoms on deployment and all were asymptomatic at the time of medical assessment. The major infection sites were Sub-Saharan Africa followed by Northern Africa and the Middle East. Conclusions Deployment of police officers to tropical deployment sites on United Nations missions is associated with a considerable acquisition risk of gastrointestinal pathogens in a quantitatively relevant minority. Post-deployment screening is advisable to facilitate therapeutic and hygiene-related consequences.
Collapse
Affiliation(s)
- Matthias Halfter
- 1Department of Tropical Medicine and Infectious Diseases, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | | | - Ralf Matthias Hagen
- 3Department of Microbiology and Hospital Hygiene, Bundeswehr Central Hospital Koblenz, Koblenz, Germany
| | - Hagen Frickmann
- 4Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany.,5Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| |
Collapse
|
16
|
Wiemer D, Schwarz NG, Burchard GD, Frickmann H, Loderstaedt U, Hagen RM. Surveillance of enteropathogenic bacteria, protozoa and helminths in travellers returning from the tropics. Eur J Microbiol Immunol (Bp) 2020; 10:147-155. [PMID: 32910786 PMCID: PMC7592519 DOI: 10.1556/1886.2020.00015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/11/2020] [Indexed: 11/19/2022] Open
Abstract
Diarrhoea is a frequent symptom associated with travelling to tropical regions, but the cause is often not found. Epidemiology was assessed including up-to-date real-time PCR approaches.We analysed datasets of 528 patients who presented at the Bernhard Nocht Institute for Tropical Medicine in Hamburg, Germany, between 2006 and 2010 for screening purposes or because of diarrhoea. Stool samples were obtained and investigated by microscopy, bacterial culture, two PCR assays targeting Entamoeba histolytica, Entamoeba dispar, Giardia duodenalis, and Cryptosporidium parvum, or Salmonella spp., Shigella/EIEC spp., Campylobacter jejuni, and Yersinia spp.Among patients with gastrointestinal symptoms, 51% tested positive for bacteria or parasites, of which 66% had a known enteropathogenic potential. In patients without diarrhoea, 53% (n = 80) were positive, and 33% of these cases harboured agents of pathogenic potential. Association with clinical symptoms was primarily found for bacterial infections. Blastocystis hominis, however, was more frequent in asymptomatic than in symptomatic travellers.In conclusion, the study stresses the etiological relevance of bacterial gastroenteritis in travellers returning from the tropics, the need for molecular approaches to increase diagnostic sensitivity and demonstrates that asymptomatic carriage of enteropathogens after prolonged stays in the tropics is similarly frequent compared with symptomatic infections in travellers.
Collapse
Affiliation(s)
- Dorothea Wiemer
- 1Department of Tropical Medicine at the Bernhard Nocht Institute, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | | | | | - Hagen Frickmann
- 1Department of Tropical Medicine at the Bernhard Nocht Institute, Bundeswehr Hospital Hamburg, Hamburg, Germany.,3Institute for Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| | | | - Ralf-Matthias Hagen
- 4Department for Microbiology and Hospital Hygiene, Bundeswehr Central Hospital Koblenz, Koblenz, Germany
| |
Collapse
|
17
|
Abstract
The gut microbiome is an exciting new area of research in chronic liver disease. It has shown promise in expanding our understanding of these complicated disease processes and has opened up new treatment modalities. The aim of this review is to increase understanding of the microbiome and explain the collection and analysis process in the context of liver disease. It also looks at our current understanding of the role of the microbiome in the wide spectrum of chronic liver diseases and how it is being used in current therapies and treatments.
Collapse
Affiliation(s)
- Bradley Reuter
- Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University, McGuire VA Medical Center, 1201 Broad Rock Boulevard, Richmond, VA 23249, USA
| | - Jasmohan S Bajaj
- Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University, McGuire VA Medical Center, 1201 Broad Rock Boulevard, Richmond, VA 23249, USA.
| |
Collapse
|
18
|
Hahn A, Frickmann H, Zautner AE. Impact of Case Definitions on Efficacy Estimation in Clinical Trials-A Proof-of-Principle Based on Historical Examples. Antibiotics (Basel) 2020; 9:antibiotics9070379. [PMID: 32635553 PMCID: PMC7400704 DOI: 10.3390/antibiotics9070379] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/24/2020] [Accepted: 07/01/2020] [Indexed: 12/03/2022] Open
Abstract
Efficacy estimations in clinical trials are based on case definitions. Commonly, they are a more or less complex set of conditions that have to be fulfilled in order to define a clinical case. In the simplest variant, such a case is identical with a single positive diagnostic test result. Frequently, however, case definitions are more complex. Further, their conditions often ignore the inherent logical structure of symptoms and disease: A symptom or a set of symptoms may be necessary but not sufficient for the unambiguous identification of a case. After describing the structure of case definitions and its impact on efficacy estimations, we exemplify this impact using data from two clinical trials dealing with the effectiveness of the vaginal application of tenofovir gel for the prevention of HIV infections and with the therapeutic effects of fecal transplantation on recurrent Clostridium difficile infections. We demonstrate that the diagnostic performance of case definitions affects efficacy estimations for interventions in clinical trials. The potential risk of bias and uncertainty is high, irrespective of the complexity of the case definition. Accordingly, case definitions in clinical trials should focus on specificity in order to avoid the risk of bias.
Collapse
Affiliation(s)
- 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: ; Tel.: +49-40-6947-28743
| | - Andreas E. Zautner
- Institut für Medizinische Mikrobiologie, Universitätsmedizin Göttingen, 37075 Göttingen, Germany;
| |
Collapse
|
19
|
Köller T, Hahn A, Altangerel E, Verweij JJ, Landt O, Kann S, Dekker D, May J, Loderstädt U, Podbielski A, Frickmann H. Comparison of commercial and in-house real-time PCR platforms for 15 parasites and microsporidia in human stool samples without a gold standard. Acta Trop 2020; 207:105516. [PMID: 32371221 DOI: 10.1016/j.actatropica.2020.105516] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/20/2020] [Accepted: 04/20/2020] [Indexed: 12/11/2022]
Abstract
INTRODUCTION A test comparison of in-house and commercial real-time PCR (qPCR) kits for the detection of human parasites and microsporidia in stool samples was conducted without a gold standard. Three different commercial kits were included in the comparison, with a range of 3-15 different PCR targets, while 14 targets were covered by in-house testing, so not all 16 target pathogens were covered by all assays. METHODS Residual materials from nucleic acid extractions of stool samples with very high likelihood of being colonized or infected by at least one enteric parasite species or microsporidia were tested. In all, 500 DNA samples were analyzed, but due to limited sample volume, only 250 of the 500 samples were tested per assay. Each sample was assessed with the qPCR platforms being compared and cycle threshold (Ct) values were included in a descriptive comparison. RESULTS Depending on the assay applied, qPCR detected per 250 tested samples Giardia duodenalis (184-205), Blastocystis spp. (174-183), Trichuris trichiura (118-120), Ascaris lumbricoides (79-96), Necator americanus (78-106), Hymenolepis nana (40-42), Cryptosporidium spp. (27-36), Dientamoeba fragilis (26-28), Schistosoma spp. (13-23), Enterobius vermicularis (8-14), Entamoeba histolytica (7-16), Strongyloides stercoralis (6-38), Cyclospora spp. (6-13), Taenia spp. (1-4), microsporidia (1-5), and Ancylostoma spp. (1-2). Inter-assay agreement kappa was almost perfect (0.81-1) for Dientamoeba fragilis, Hymenolepis nana, Cryptosporidium spp., and Ascaris lumbricoides, substantial (0.61-0.8) for Necator americanus, Blastocystis spp., Ancylostoma spp., Giardia duodenalis, Schistosoma spp., Trichuris trichiura, and Enterobius vermicularis, moderate (0.41-0.6) for Entamoeba histolytica, fair (0.21-0.4) for microsporidia, slight (0-0.2) for Cyclospora spp. and Strongyloides stercoralis, and poor (<0) for Taenia spp. CONCLUSIONS Varying inter-assay agreement makes interpretation of microsporidia and parasite PCR in stool samples challenging. Intra-assay agreement had been controlled during the developing of the assays. Future studies, e.g., with optimized nucleic acid procedures and including microscopically characterized samples, are advisable.
Collapse
|
20
|
Hahn A, Podbielski A, Meyer T, Zautner AE, Loderstädt U, Schwarz NG, Krüger A, Cadar D, Frickmann H. On detection thresholds-a review on diagnostic approaches in the infectious disease laboratory and the interpretation of their results. Acta Trop 2020; 205:105377. [PMID: 32007448 DOI: 10.1016/j.actatropica.2020.105377] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 11/18/2019] [Accepted: 01/29/2020] [Indexed: 02/06/2023]
Abstract
Diagnostic testing in the infectious disease laboratory facilitates decision-making by physicians at the bedside as well as epidemiological assessments and surveillance at study level. Problems may arise if test results are uncritically considered as being the same as the unknown true value. To allow a better understanding, the influence of external factors on the interpretation of test results is introduced with the example of prevalence, followed by the presentation of strengths and weaknesses of important techniques in the infectious disease laboratory like microscopy, cultural diagnostics, serology, mass spectrometry, nucleic acid amplification and hypothesis-free metagenomic sequencing with focus on basic, high-technology and potential future approaches. Special problems like multiplex testing as well as uncertainty of test evaluations, if no gold standard is available, are also stressed with a final glimpse on emerging future technologies for the infectious disease laboratory. In the conclusions, suitability for point-of-care-testing and field laboratory applications is summarized. The aim is to illustrate the limitations of diagnostic accuracy to both clinicians and study planners and to stress the importance of close cooperation with experts in laboratory disciplines so as to avoid potentially critical misunderstandings due to inappropriate interpretation of diagnostic test results.
Collapse
Affiliation(s)
- Andreas Hahn
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| | - Andreas Podbielski
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| | - Thomas Meyer
- Department of Dermatology, St. Josef Hospital, Bochum, Germany
| | - Andreas Erich Zautner
- Institut für Medizinische Mikrobiologie, Universitätsmedizin Göttingen, Göttingen, Germany
| | - Ulrike Loderstädt
- Bernhard Nocht Institute for Tropical Medicine Hamburg, Hamburg, Germany
| | | | - Andreas Krüger
- Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany
| | - Daniel Cadar
- Bernhard Nocht Institute for Tropical Medicine Hamburg, Hamburg, Germany
| | - Hagen Frickmann
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany; Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany.
| |
Collapse
|
21
|
Prudden HJ, Hasso-Agopsowicz M, Black RE, Troeger C, Reiner RC, Breiman RF, Jit M, Kang G, Lamberti L, Lanata CF, Lopman BA, Ndifon W, Pitzer VE, Platts-Mills JA, Riddle MS, Smith PG, Hutubessy R, Giersing B. Meeting Report: WHO Workshop on modelling global mortality and aetiology estimates of enteric pathogens in children under five. Cape Town, 28-29th November 2018. Vaccine 2020; 38:4792-4800. [PMID: 32253097 PMCID: PMC7306158 DOI: 10.1016/j.vaccine.2020.01.054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 01/15/2020] [Indexed: 12/22/2022]
Abstract
Investment in vaccine product development should be guided by up-to-date and transparent global burden of disease estimates, which are also fundamental to policy recommendation and vaccine introduction decisions. For low- and middle-income countries (LMICs), vaccine prioritization is primarily driven by the number of deaths caused by different pathogens. Enteric diseases are known to be a major cause of death in LMICs. The two main modelling groups providing mortality estimates for enteric diseases are the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, Seattle and the Maternal Child Epidemiology Estimation (MCEE) group, led by Johns Hopkins Bloomberg School of Public Health. Whilst previous global diarrhoea mortality estimates for under five-year-olds from these two groups were closely aligned, more recent estimates for 2016 have diverged, particularly with respect to numbers of deaths attributable to different enteric pathogens. This has impacted prioritization and investment decisions for vaccines in the development pipeline. The mission of the Product Development for Vaccines Advisory Committee (PDVAC) at the World Health Organisation (WHO) is to accelerate product development of vaccines and technologies that are urgently needed and ensure they are appropriately targeted for use in LMICs. At their 2018 meeting, PDVAC recommended the formation of an independent working group of subject matter experts to explore the reasons for the difference between the IHME and MCEE estimates, and to assess the respective strengths and limitations of the estimation approaches adopted, including a review of the data on which the estimates are based. Here, we report on the proceedings and recommendations from a consultation with the working group of experts, the IHME and MCEE modelling groups, and other key stakeholders. We briefly review the methodological approaches of both groups and provide a series of proposals for investigating the drivers for the differences in enteric disease burden estimates.
Collapse
Affiliation(s)
- H J Prudden
- Initiative for Vaccine Research, World Health Organisation, CH-1211 Geneva, Switzerland
| | - M Hasso-Agopsowicz
- Initiative for Vaccine Research, World Health Organisation, CH-1211 Geneva, Switzerland
| | - R E Black
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - C Troeger
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA 98121, USA
| | - R C Reiner
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA 98121, USA
| | - R F Breiman
- Global Health Institute, Emory University, Atlanta, GA, USA
| | - M Jit
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, United Kingdom; Modelling and Economics Unit, National Infections Service, Public Health England, United Kingdom; School of Public Health, University of Hong Kong, Hong Kong
| | - G Kang
- Translational Health Science and Technology Institute, Faridabad, India
| | - L Lamberti
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - C F Lanata
- Instituto de Investigacion Nutricional, Lima, Peru; Department of Pediatrics, School of Medicine, Vanderbilt University, Nashville, TN 37027, USA
| | - B A Lopman
- Global Health Institute, Emory University, Atlanta, GA, USA
| | - W Ndifon
- African Institute for Mathematical Sciences, Cape Town, South Africa
| | - V E Pitzer
- Department of Epidemiology and Microbial Diseases, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - J A Platts-Mills
- Division of Infectious Diseases & International Health, University of Virginia, Charlottesville, VA 22908, USA
| | - M S Riddle
- Uniformed Services University, Bethesda, MD 120814, USA
| | - P G Smith
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, United Kingdom
| | - R Hutubessy
- Initiative for Vaccine Research, World Health Organisation, CH-1211 Geneva, Switzerland
| | - B Giersing
- Initiative for Vaccine Research, World Health Organisation, CH-1211 Geneva, Switzerland.
| |
Collapse
|
22
|
Workflow optimization for syndromic diarrhea diagnosis using the molecular Seegene Allplex™ GI-Bacteria(I) assay. Eur J Clin Microbiol Infect Dis 2020; 39:1245-1250. [PMID: 32026192 PMCID: PMC7303052 DOI: 10.1007/s10096-020-03837-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 01/29/2020] [Indexed: 12/24/2022]
Abstract
Syndromic panel-based molecular testing has been suggested to improve and accelerate microbiological diagnosis. We aimed to analyze workflow improvements when using the multiplex Seegene Allplex™ GI-Bacteria(I) assay as a first-line assay for bacterial diarrhea. Technical assay evaluation was done using spiked stool samples and stored patient samples. After implementation of the assay in the routine clinical workflow, an analysis of 5032 clinical samples analyzed by the Seegene assay and 4173 control samples examined by culture in a similar time period 1 year earlier was performed. Sensitivity of the assay was shown to be between 0.4 and 95.9 genome equivalents/PCR. For 159 positive patient samples with a composite reference of culture and/or a molecular assay, the sensitivity of the assay was 100% for Campylobacter, 92% for Salmonella, 89% for Aeromonas, and 83% for Shigella. Sensitivity for C. difficile toxin B detection was 93.9%. The comparison of clinical samples obtained in two 8-month periods showed increased detection rates for Aeromonas (2.90%vs. 0.34%), Campylobacter spp. (2.25% vs. 1.34%), Shigella spp. (0.42% vs. 0.05%) whereas detection of Salmonella was slightly decreased (0.46% vs. 0.67%) when using the Seegene assay. An analysis of the time-to-result showed that the median dropped from 52.7 to 26.4 h when using the molecular panel testing. The Seegene Allplex™ GI-Bacteria(I) assay allows accelerated, reliable detection of major gastrointestinal bacteria roughly within 1 day. Workload is reduced, specifically in a low-prevalence setting.
Collapse
|
23
|
Hahn A, Meyer CG, Frickmann H. Impact of diagnostic methods on efficacy estimation - a proof-of-principle based on historical examples. Trop Med Int Health 2019; 25:357-363. [PMID: 31758838 DOI: 10.1111/tmi.13351] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Accurate diagnostic methods are essential for evaluating treatment efficacy in clinical trials, including vaccine trials. Although a plethora of studies assessing novel or modified treatment options is available, clinical trials evaluating the sensitivity and specificity of diagnostic methods in compliance with the demands of drug registration trials are scarce. We assessed the accuracy of diagnostic methods in two vaccine trials conducted in 1995 and 2009 to demonstrate the impact of sensitivity and specificity on efficacy estimations. METHODS We applied the sensitivity- and specificity-adjusted vaccine efficacy estimator of Lachenbruch for modelling the impact of test characteristics on the outcome of the two vaccine trials by varying diagnostic specificity. RESULTS Because of non-ideal diagnostic sensitivity and specificity, the estimation of vaccine efficacy is compromised. We demonstrate the impact of diagnostic accuracy on efficacy estimations with increasing confidence limits. CONCLUSIONS Because sensitivity and specificity less than one have a direct impact on efficacy estimations in clinical trials, evaluation of diagnostic methods should lead to a level of evidence comparable with the efficacy assessment of novel treatment options. Furthermore, statistical methods adjusted for sensitivity and specificity of diagnostic methods should be applied for efficacy estimations, or this lack of confidence has to be taken into account when interpreting the results of trials.
Collapse
Affiliation(s)
- Andreas Hahn
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany
| | - Christian G Meyer
- Institute of Tropical Medicine, Eberhard Karls University, Tübingen, Germany.,Duy Tan University, Đà Nẵng, Vietnam.,Vietnamese-German Center of Medical Research, Hanoi, Vietnam
| | - Hagen Frickmann
- Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany.,Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, Hamburg, Germany
| |
Collapse
|
24
|
Adamek M, Teitge F, Steinhagen D. Quantitative diagnostics of gill diseases in common carp: not as simple as it seems. DISEASES OF AQUATIC ORGANISMS 2019; 134:197-207. [PMID: 31120037 DOI: 10.3354/dao03374] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
During a disease outbreak, affected fish exhibit particular clinical signs, and the task in veterinary diagnostics is to identify the causative agent(s) as a prerequisite for appropriate treatment measures. In this study, we present an outbreak of a multifactorial gill disease in a cohort of ornamental koi Cyprinus carpio with gill necrosis as the main exterior clinical sign. By means of pathogen identification and determining pathogen abundance in various tissues, mortality of individual fish was found to be caused by different agents. Three out of 5 diseased individuals suffered from koi herpesvirus disease (KHVD) associated with a systemic infection with cyprinid herpesvirus 3 (CyHV-3), 1 fish succumbed to koi sleepy disease (KSD) caused by a high carp edema virus (CEV) load in the gills co-infected with CyHV-3 and flavobacteria, and the last fish had low loads of both viruses but high flavobacteria and Ichthyobodo burdens and most likely died from an interaction of these bacterial and parasitic agents. The results indicated that correct identification of the agent responsible for the observed clinical signs or mortality during co-infection might require quantitative determination of the abundance of the pathogens as well as detailed knowledge of the infection biology of these pathogens.
Collapse
Affiliation(s)
- Mikolaj Adamek
- Fish Disease Research Unit, Centre of Infectious Diseases, University of Veterinary Medicine, 30559 Hannover, Germany
| | | | | |
Collapse
|
25
|
Nelson MM, Waldron CL, Bracht JR. Rapid molecular detection of macrolide resistance. BMC Infect Dis 2019; 19:144. [PMID: 30755177 PMCID: PMC6373131 DOI: 10.1186/s12879-019-3762-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 01/30/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Emerging antimicrobial resistance is a significant threat to human health. However, methods for rapidly diagnosing antimicrobial resistance generally require multi-day culture-based assays. Macrolide efflux gene A, mef(A), provides resistance against erythromycin and azithromycin and is known to be laterally transferred among a wide range of bacterial species. METHODS We use Recombinase Polymerase Assay (RPA) to detect the antimicrobial resistance gene mef(A) from raw lysates without nucleic acid purification. To validate these results we performed broth dilution assays to assess antimicrobial resistance to erythromycin and ampicillin (a negative control). RESULTS We validate the detection of mef(A) in raw lysates of Streptococcus pyogenes, S. pneumoniae, S. salivarius, and Enterococcus faecium bacterial lysates within 7-10 min of assay time. We show that detection of mef(A) accurately predicts real antimicrobial resistance assessed by traditional culture methods, and that the assay is robust to high levels of spiked-in non-specific nucleic acid contaminant. The assay was unaffected by single-nucleotide polymorphisms within divergent mef(A) gene sequences, strengthening its utility as a robust diagnostic tool. CONCLUSIONS This finding opens the door to implementation of rapid genomic diagnostics in a clinical setting, while providing researchers a rapid, cost-effective tool to track antibiotic resistance in both pathogens and commensal strains.
Collapse
Affiliation(s)
- Megan M. Nelson
- Department of Biology, American University, Washington, DC 20016 USA
| | | | - John R. Bracht
- Department of Biology, American University, Washington, DC 20016 USA
| |
Collapse
|
26
|
Reali S, Najib EY, Treuerné Balázs KE, Chern Hui Tan A, Váradi L, Hibbs DE, Groundwater PW. Novel diagnostics for point-of-care bacterial detection and identification. RSC Adv 2019; 9:21486-21497. [PMID: 35521339 PMCID: PMC9066158 DOI: 10.1039/c9ra03118a] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 06/30/2019] [Indexed: 12/20/2022] Open
Abstract
In addition to limiting the effectiveness of antimicrobial agents, antimicrobial resistance (AMR) is a significant global health concern as it is responsible for significant mortality/morbidity and increased economic burdens on healthcare systems. Diagnostic tests have been suggested as a means of prolonging the effectiveness of current antimicrobials; culture and other conventional diagnostics are hindered in their practicality as they are time- and labour intensive to perform. Point-of-care (POC) testing is performed near where the patient is being treated and can provide timely results that allow evidence based clinical interventions to be made. This review aims to outline the chemical principles behind some novel and emerging diagnostic techniques which have the required speed, simplicity, effectiveness and low-cost for incorporation into POC devices which can be used to inform and optimize antimicrobial use. The WHO global action plan on antimicrobial resistance outlines the need for new diagnostic tools. Point-of-care testing for bacterial infections would enable clinically meaningful interventions using methods that are rapid, low-cost, easy-to-operate, and portable.![]()
Collapse
Affiliation(s)
- Savannah Reali
- The University of Sydney School of Pharmacy
- Camperdown Campus
- Sydney
- Australia
| | - Elias Y. Najib
- The University of Sydney School of Pharmacy
- Camperdown Campus
- Sydney
- Australia
| | | | | | | | - David E. Hibbs
- The University of Sydney School of Pharmacy
- Camperdown Campus
- Sydney
- Australia
| | | |
Collapse
|
27
|
Allaband C, McDonald D, Vázquez-Baeza Y, Minich JJ, Tripathi A, Brenner DA, Loomba R, Smarr L, Sandborn WJ, Schnabl B, Dorrestein P, Zarrinpar A, Knight R. Microbiome 101: Studying, Analyzing, and Interpreting Gut Microbiome Data for Clinicians. Clin Gastroenterol Hepatol 2019; 17:218-230. [PMID: 30240894 PMCID: PMC6391518 DOI: 10.1016/j.cgh.2018.09.017] [Citation(s) in RCA: 161] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 09/13/2018] [Indexed: 02/07/2023]
Abstract
Advances in technical capabilities for reading complex human microbiomes are leading to an explosion of microbiome research, leading in turn to intense interest among clinicians in applying these techniques to their patients. In this review, we discuss the content of the human microbiome, including intersubject and intrasubject variability, considerations of study design including important confounding factors, and different methods in the laboratory and on the computer to read the microbiome and its resulting gene products and metabolites. We highlight several common pitfalls for clinicians, including the expectation that an individual's microbiome will be stable, that diet can induce rapid changes that are large compared with the differences among subjects, that everyone has essentially the same core stool microbiome, and that different laboratory and computational methods will yield essentially the same results. We also highlight the current limitations and future promise of these techniques, with the expectation that an understanding of these considerations will help accelerate the path toward routine clinical application of these techniques developed in research settings.
Collapse
Affiliation(s)
- Celeste Allaband
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California
| | - Daniel McDonald
- Department of Pediatrics, University of California San Diego, La Jolla, California
| | | | - Jeremiah J. Minich
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California
| | - Anupriya Tripathi
- Division of Biological Sciences, University of California San Diego, La Jolla, California
| | - David A. Brenner
- Department of Medicine, University of California San Diego, La Jolla, California
| | - Rohit Loomba
- Department of Medicine, University of California San Diego, La Jolla, California, Center for Microbiome Innovation, University of California San Diego, La Jolla, California
| | - Larry Smarr
- Center for Microbiome Innovation, University of California San Diego, La Jolla, California, Department of Computer Science and Engineering, University of California San Diego, La Jolla, California, California Institute of Telecommunications and Information Technology, University of California San Diego, La Jolla, California
| | - William J. Sandborn
- Center for Microbiome Innovation, University of California San Diego, La Jolla, California, Division of Gastroenterology, Veterans Administration San Diego Health System, La Jolla, California
| | - Bernd Schnabl
- Department of Medicine, University of California San Diego, La Jolla, California, Center for Microbiome Innovation, University of California San Diego, La Jolla, California, Division of Gastroenterology, Veterans Administration San Diego Health System, La Jolla, California
| | - Pieter Dorrestein
- Department of Pediatrics, University of California San Diego, La Jolla, California, Center for Microbiome Innovation, University of California San Diego, La Jolla, California, Skaggs School of Pharmacy, University of California San Diego, La Jolla, California
| | - Amir Zarrinpar
- Department of Medicine, University of California San Diego, La Jolla, California, Center for Microbiome Innovation, University of California San Diego, La Jolla, California, Division of Gastroenterology, Veterans Administration San Diego Health System, La Jolla, California
| | - Rob Knight
- Department of Pediatrics, University of California San Diego, La Jolla, California; Center for Microbiome Innovation, University of California San Diego, La Jolla, California; Department of Computer Science and Engineering, University of California San Diego, La Jolla, California; Department of Bioengineering, University of California San Diego, La Jolla, California.
| |
Collapse
|
28
|
Multicenter performance evaluation of the Unyvero IAI cartridge for detection of intra-abdominal infections. Eur J Clin Microbiol Infect Dis 2018; 37:2107-2115. [PMID: 30094522 DOI: 10.1007/s10096-018-3345-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/02/2018] [Indexed: 10/28/2022]
Abstract
Intra-abdominal infections (IAIs) are one of the most common type of infections in patients with sepsis and an important cause of death in intensive care units. Early detection and treatment are necessary to reduce patient complications and improve outcomes. The Unyvero IAI Application (Curetis GmbH) is the first automated assay to rapidly and simultaneously identify a large panel of bacteria, fungi, toxins, and antibiotic resistance markers directly from IAI-related samples. The assay was evaluated in four European clinical laboratories in comparison to routine microbiological practices. A total of 300 clinical samples were tested with an overall sensitivity of 89.3% and specificity of 99.5%, while time to results was reduced by an average of about 17 h compared to identification (ID) results and 41 h compared to full antibiotic susceptibility testing (AST) results. The Unyvero IAI was able to detect additional microorganisms compared with culture, in particular anaerobes, with most detections confirmed by sequencing. The most frequent resistance markers detected were mecA/mecC (n = 25), aacA4 (n = 20), and blaCTX-M (n = 17) and carbapenemase genes were identified in nine specimens. Further studies are now required to determine the clinical impact of this new rapid test which could play a role in the successful treatment of IAI.
Collapse
|
29
|
Walter JM, Wunderink RG. Testing for Respiratory Viruses in Adults With Severe Lower Respiratory Infection. Chest 2018; 154:1213-1222. [PMID: 29908153 PMCID: PMC6224704 DOI: 10.1016/j.chest.2018.06.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 05/29/2018] [Accepted: 06/04/2018] [Indexed: 12/31/2022] Open
Abstract
Viral pathogens are a common cause of severe lower respiratory tract infection in adults. Our ability to rapidly and accurately identify viral infections has dramatically improved as slow culture-based techniques have been largely replaced by multiplex high-throughput systems. Given these advances, reevaluation of the role of respiratory viral testing in adults presenting with lower respiratory tract infection is important. This article reviews the potential benefits of testing, provides an overview of the most commonly used diagnostic techniques, and considers whether current evidence supports routine testing.
Collapse
Affiliation(s)
- James M Walter
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL.
| | - Richard G Wunderink
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL
| |
Collapse
|
30
|
Lääveri T, Vilkman K, Pakkanen S, Kirveskari J, Kantele A. Despite antibiotic treatment of travellers' diarrhoea, pathogens are found in stools from half of travellers at return. Travel Med Infect Dis 2018; 23:49-55. [PMID: 29702254 DOI: 10.1016/j.tmaid.2018.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 03/24/2018] [Accepted: 04/09/2018] [Indexed: 01/01/2023]
Abstract
BACKGROUND Among visitors to the (sub)tropics, 20-50% contract travellers' diarrhoea (TD) and 5-30% take antibiotics. While shortening the duration of illness, antimicrobials predispose to acquisition of multi-drug resistant bacteria. Therefore, liberal use is no longer advocated. Although antibiotics kill pathogens, no data support the view that they could prevent post-infectious sequelae. We investigated how antibiotic use for TD abroad impacts the pathogen findings at return. MATERIALS AND METHODS We revisited 456 travellers' clinical data and stool pathogens examined by qPCR for Salmonella, Yersinia, Campylobacter, Shigella, Vibrio cholerae and enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enterohaemorrhagic (EHEC) and enteroinvasive (EIEC) Escherichia coli. RESULTS Among travellers with TD, antibiotic users had pathogen-positive samples less frequently than non-users (50% versus 83%). The difference was significant for EPEC (23% versus 47%) and EAEC (27% versus 54%), but not ETEC (17% versus 26%) or the other pathogens. Shigella/EIEC was found more often among antibiotic users than non-users (4% versus 1%). CONCLUSION Despite antibiotic treatment of TD, half of the users still had stool pathogens at return, reflecting either antibiotic resistance of pathogens or recolonisation/reinfection while abroad. Treatment of TD with antibiotics during travel should not be interpreted to indicate eradication of pathogens.
Collapse
Affiliation(s)
- Tinja Lääveri
- Inflammation Center, Division of Infectious Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland, POB 348, FIN-00029 HUS, Finland.
| | - Katri Vilkman
- Inflammation Center, Division of Infectious Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland, POB 348, FIN-00029 HUS, Finland.
| | - Sari Pakkanen
- Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland, POB 21, FIN-00014 Helsinki, Finland.
| | - Juha Kirveskari
- Helsinki University Hospital Laboratory (HUSLAB), Department of Bacteriology, Helsinki, Finland, POB 720, FIN-00029 HUS, Finland; Mobidiag Ltd, Espoo, Finland, Keilaranta 16 A, FIN-02150 Espoo Finland.
| | - Anu Kantele
- Inflammation Center, Division of Infectious Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland, POB 348, FIN-00029 HUS, Finland; Clinicum, University of Helsinki, Helsinki, Finland, POB 63, FI-00014 Helsinki, Finland; Aava Travel Clinic, Medical Centre Aava, Helsinki, Finland, Annankatu 32, FIN-00100 Helsinki, Finland; Unit of Infectious Diseases, Department of Medicine/Solna, Karolinska Institutet, Stockholm, Sweden, SE-17176 Stockholm, Sweden.
| |
Collapse
|
31
|
Tang YW, Stratton CW. Interpretation and Relevance of Advanced Technique Results. ADVANCED TECHNIQUES IN DIAGNOSTIC MICROBIOLOGY 2018. [PMCID: PMC7120226 DOI: 10.1007/978-3-319-95111-9_31] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Advanced techniques in the field of diagnostic microbiology have made amazing progress over the past 25 years due largely to a technological revolution in the molecular aspects of microbiology [1, 2]. In particular, rapid molecular methods for nucleic acid amplification and characterization combined with automation in the clinical microbiology laboratory as well as user-friendly software and robust laboratory informatics systems have significantly broadened the diagnostic capabilities of modern clinical microbiology laboratories. Molecular methods such as nucleic acid amplification tests (NAATs) rapidly are being developed and introduced in the clinical laboratory setting [3, 4]. Indeed, every section of the clinical microbiology laboratory, including bacteriology, mycology, mycobacteriology, parasitology, and virology, has benefited from these advanced techniques. Because of the rapid development and adaptation of these molecular techniques, the interpretation and relevance of the results produced by such molecular methods continues to lag behind. The purpose of this chapter is to review, update, and discuss the interpretation and relevance of results produced by these advanced molecular techniques.
Collapse
Affiliation(s)
- Yi-Wei Tang
- Departments of Laboratory Medicine and Internal Medicine, Memorial Sloan Kettering Cancer Center, New York, NY USA
| | - Charles W. Stratton
- Department of Pathology, Microbiology and Immunology and Medicine, Vanderbilt University Medical Center, Nashville, TN USA
| |
Collapse
|