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Aralar A, Goshia T, Ramchandar N, Lawrence SM, Karmakar A, Sharma A, Sinha M, Pride DT, Kuo P, Lecrone K, Chiu M, Mestan KK, Sajti E, Vanderpool M, Lazar S, Crabtree M, Tesfai Y, Fraley SI. Universal Digital High-Resolution Melt Analysis for the Diagnosis of Bacteremia. J Mol Diagn 2024; 26:349-363. [PMID: 38395408 PMCID: PMC11090205 DOI: 10.1016/j.jmoldx.2024.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 01/04/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
Fast and accurate diagnosis of bloodstream infection is necessary to inform treatment decisions for septic patients, who face hourly increases in mortality risk. Blood culture remains the gold standard test but typically requires approximately 15 hours to detect the presence of a pathogen. We, therefore, assessed the potential for universal digital high-resolution melt (U-dHRM) analysis to accomplish faster broad-based bacterial detection, load quantification, and species-level identification directly from whole blood. Analytical validation studies demonstrated strong agreement between U-dHRM load measurement and quantitative blood culture, indicating that U-dHRM detection is highly specific to intact organisms. In a pilot clinical study of 17 whole blood samples from pediatric patients undergoing simultaneous blood culture testing, U-dHRM achieved 100% concordance when compared with blood culture and 88% concordance when compared with clinical adjudication. Moreover, U-dHRM identified the causative pathogen to the species level in all cases where the organism was represented in the melt curve database. These results were achieved with a 1-mL sample input and sample-to-answer time of 6 hours. Overall, this pilot study suggests that U-dHRM may be a promising method to address the challenges of quickly and accurately diagnosing a bloodstream infection.
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Affiliation(s)
- April Aralar
- Department of Bioengineering, University of California, San Diego, La Jolla, California
| | - Tyler Goshia
- Department of Bioengineering, University of California, San Diego, La Jolla, California
| | - Nanda Ramchandar
- Department of Pediatrics, Naval Medical Center San Diego, San Diego, California; Division of Infectious Diseases, Department of Pediatrics, University of California, San Diego, La Jolla, California
| | - Shelley M Lawrence
- Division of Neonatology, Department of Pediatrics, The University of Utah, Salt Lake City, Utah
| | | | | | | | - David T Pride
- Department of Pathology, University of California, San Diego, La Jolla, California
| | - Peiting Kuo
- Department of Pathology, University of California, San Diego, La Jolla, California
| | - Khrissa Lecrone
- Department of Pathology, University of California, San Diego, La Jolla, California
| | - Megan Chiu
- Department of Pathology, University of California, San Diego, La Jolla, California
| | - Karen K Mestan
- Division of Neonatology, Department of Pediatrics, University of California, San Diego, La Jolla, California
| | - Eniko Sajti
- Division of Neonatology, Department of Pediatrics, University of California, San Diego, La Jolla, California
| | - Michelle Vanderpool
- Department of Pathology and Laboratory Medicine, Rady Children's Hospital-San Diego, San Diego, California
| | - Sarah Lazar
- Division of Neonatology, Department of Pediatrics, University of California, San Diego, La Jolla, California
| | - Melanie Crabtree
- Division of Neonatology, Department of Pediatrics, University of California, San Diego, La Jolla, California
| | - Yordanos Tesfai
- Division of Neonatology, Department of Pediatrics, University of California, San Diego, La Jolla, California
| | - Stephanie I Fraley
- Department of Bioengineering, University of California, San Diego, La Jolla, California.
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2
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Stepien TA, Singletary LA, Guerra FE, Karlinsey JE, Libby SJ, Jaslow SL, Gaggioli MR, Gibbs KD, Ko DC, Brehm MA, Greiner DL, Shultz LD, Fang FC. Nuclear factor kappa B-dependent persistence of Salmonella Typhi and Paratyphi in human macrophages. mBio 2024; 15:e0045424. [PMID: 38497655 PMCID: PMC11005419 DOI: 10.1128/mbio.00454-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 02/21/2024] [Indexed: 03/19/2024] Open
Abstract
Salmonella serovars Typhi and Paratyphi cause a prolonged illness known as enteric fever, whereas other serovars cause acute gastroenteritis. Mechanisms responsible for the divergent clinical manifestations of nontyphoidal and enteric fever Salmonella infections have remained elusive. Here, we show that S. Typhi and S. Paratyphi A can persist within human macrophages, whereas S. Typhimurium rapidly induces apoptotic macrophage cell death that is dependent on Salmonella pathogenicity island 2 (SPI2). S. Typhi and S. Paratyphi A lack 12 specific SPI2 effectors with pro-apoptotic functions, including nine that target nuclear factor κB (NF-κB). Pharmacologic inhibition of NF-κB or heterologous expression of the SPI2 effectors GogA or GtgA restores apoptosis of S. Typhi-infected macrophages. In addition, the absence of the SPI2 effector SarA results in deficient signal transducer and activator of transcription 1 (STAT1) activation and interleukin 12 production, leading to impaired TH1 responses in macrophages and humanized mice. The absence of specific nontyphoidal SPI2 effectors may allow S. Typhi and S. Paratyphi A to cause chronic infections. IMPORTANCE Salmonella enterica is a common cause of gastrointestinal infections worldwide. The serovars Salmonella Typhi and Salmonella Paratyphi A cause a distinctive systemic illness called enteric fever, whose pathogenesis is incompletely understood. Here, we show that enteric fever Salmonella serovars lack 12 specific virulence factors possessed by nontyphoidal Salmonella serovars, which allow the enteric fever serovars to persist within human macrophages. We propose that this fundamental difference in the interaction of Salmonella with human macrophages is responsible for the chronicity of typhoid and paratyphoid fever, suggesting that targeting the nuclear factor κB (NF-κB) complex responsible for macrophage survival could facilitate the clearance of persistent bacterial infections.
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Affiliation(s)
- Taylor A. Stepien
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | | | - Fermin E. Guerra
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - Joyce E. Karlinsey
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Stephen J. Libby
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - Sarah L. Jaslow
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Margaret R. Gaggioli
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Kyle D. Gibbs
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Dennis C. Ko
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Michael A. Brehm
- Department of Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Dale L. Greiner
- Department of Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | | | - Ferric C. Fang
- Department of Global Health, University of Washington, Seattle, Washington, USA
- Department of Microbiology, University of Washington, Seattle, Washington, USA
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
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3
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Depew CE, McSorley SJ. The role of tissue resident memory CD4 T cells in Salmonella infection: Implications for future vaccines. Vaccine 2023; 41:6426-6433. [PMID: 37739887 DOI: 10.1016/j.vaccine.2023.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 07/20/2023] [Accepted: 09/05/2023] [Indexed: 09/24/2023]
Abstract
Salmonella infections cause a wide range of intestinal and systemic disease that affects global human health. While some vaccines are available, they do not mitigate the impact of Salmonella on endemic areas. Research using Salmonella mouse models has revealed the important role of CD4 T cells and antibody in the development of protective immunity against Salmonella infection. Recent work points to a critical role for hepatic tissue-resident memory lymphocytes in naturally acquired immunity to systemic infection. Thus, understanding the genesis and function of this Salmonella-specific population is an important objective and is the primary focus of this review. Greater understanding of how these memory lymphocytes contribute to bacterial elimination could suggest new approaches to vaccination against an important human pathogen.
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Affiliation(s)
- Claire E Depew
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, CA 95616, USA.
| | - Stephen J McSorley
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California Davis, Davis, CA 95616, USA.
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4
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Dudhane RA, Bankar NJ, Shelke YP, Badge AK. The Rise of Non-typhoidal Salmonella Infections in India: Causes, Symptoms, and Prevention. Cureus 2023; 15:e46699. [PMID: 38021876 PMCID: PMC10630329 DOI: 10.7759/cureus.46699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 10/08/2023] [Indexed: 12/01/2023] Open
Abstract
Non-typhoidal Salmonella infections (NTS) are a growing concern in India, posing a significant health risk to the population. These infections are becoming more common at worrisome rates, primarily because of inadequate surveillance. Salmonella non-typhoidal causes severe gastroenteritis and can even cause invasive infections, such as bacteremia, and focal infections, such as meningitis and septic arthritis, and is acquired through contaminated food and water sources. From moderate to severe, the symptoms might vary. Certain serovars exhibit a stronger propensity for specific syndromes, with serious infections more commonly observed in vulnerable populations. Consuming contaminated food, using inadequate sanitation procedures while handling meat from animals slaughtered, and contaminated water supplies are some of the causes of these diseases. Proper food and water treatment, better sanitary facilities, public awareness campaigns, and adherence to food safety laws are all part of prevention measures. The issue of antimicrobial resistance further emphasizes the necessity for prudent antibiotic usage. The Indian government has put in place programs including public awareness campaigns, better sanitary facilities, and stricter food safety laws. In the future, efforts should, however, concentrate on improving laws, boosting hygienic practices, and funding the development of new medicines and vaccines. These actions will lessen the burden of NTS infections in India by assisting in their prevention and management. This review aims to understand the reasons for this growing tendency, which is essential for creating efficient control and prevention strategies.
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Affiliation(s)
- Radhika A Dudhane
- Microbiology, Datta Meghe Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Nandkishor J Bankar
- Microbiology, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Yogendra P Shelke
- Microbiology, Bhaktshreshtha Kamalakarpant Laxmanrao Walwalkar Rural Medical College, Ratnagiri, IND
| | - Ankit K Badge
- Microbiology, Datta Meghe Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
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5
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Aralar A, Goshia T, Ramchandar N, Lawrence SM, Karmakar A, Sharma A, Sinha M, Pride DT, Kuo P, Lecrone K, Chiu M, Mestan K, Sajti E, Vanderpool M, Lazar S, Crabtree M, Tesfai Y, Fraley SI. Universal digital high resolution melt analysis for the diagnosis of bacteremia. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.09.07.23295215. [PMID: 37732245 PMCID: PMC10508820 DOI: 10.1101/2023.09.07.23295215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Fast and accurate diagnosis of bloodstream infection is necessary to inform treatment decisions for septic patients, who face hourly increases in mortality risk. Blood culture remains the gold standard test but typically requires ∼15 hours to detect the presence of a pathogen. Here, we assess the potential for universal digital high-resolution melt (U-dHRM) analysis to accomplish faster broad-based bacterial detection, load quantification, and species-level identification directly from whole blood. Analytical validation studies demonstrated strong agreement between U-dHRM load measurement and quantitative blood culture, indicating that U-dHRM detection is highly specific to intact organisms. In a pilot clinical study of 21 whole blood samples from pediatric patients undergoing simultaneous blood culture testing, U-dHRM achieved 100% concordance when compared with blood culture and 90.5% concordance when compared with clinical adjudication. Moreover, U-dHRM identified the causative pathogen to the species level in all cases where the organism was represented in the melt curve database. These results were achieved with a 1 mL sample input and sample-to-answer time of 6 hrs. Overall, this pilot study suggests that U-dHRM may be a promising method to address the challenges of quickly and accurately diagnosing a bloodstream infection. Universal digital high resolution melt analysis for the diagnosis of bacteremia April Aralar, Tyler Goshia, Nanda Ramchandar, Shelley M. Lawrence, Aparajita Karmakar, Ankit Sharma, Mridu Sinha, David Pride, Peiting Kuo, Khrissa Lecrone, Megan Chiu, Karen Mestan, Eniko Sajti, Michelle Vanderpool, Sarah Lazar, Melanie Crabtree, Yordanos Tesfai, Stephanie I. Fraley.
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6
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Ehrhardt K, Becker AL, Grassl GA. Determinants of persistent Salmonella infections. Curr Opin Immunol 2023; 82:102306. [PMID: 36989589 DOI: 10.1016/j.coi.2023.102306] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 03/29/2023]
Abstract
Persistent bacterial infections constitute an enormous challenge for public health. Amongst infections with other bacteria, infections with typhoidal and nontyphoidal Salmonella enterica serovars can result in long-term infections of the human and animal host. Persistent infections that are asymptomatic are difficult to identify and thus can serve as a silent reservoir for transmission. Symptomatic persistent infections are often difficult to treat as they harbor a combination of antibiotic-tolerant and antibiotic-resistant bacteria and boost the spread of genetic antibiotic resistance. In the last couple of years, the field has made some major progress in understanding the role of persisters, their reservoirs as well as their interplay with host factors in persistent Salmonella infections.
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7
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Igiri BE, Okoduwa SIR, Munirat SA, Otu-Bassey IB, Bashir A, Onyiyioza OM, Enang IA, Okoduwa UJ. Diversity in Enteric Fever Diagnostic Protocols and Recommendation for Composite Reference Standard. IRANIAN JOURNAL OF MEDICAL MICROBIOLOGY 2023; 17:22-38. [DOI: 10.30699/ijmm.17.1.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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8
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von Seidlein L. The wrongful indictment of pre-referral rectal artesunate further delays the roll-out of this lifesaving drug. THE LANCET. INFECTIOUS DISEASES 2022; 23:e208-e212. [PMID: 36549312 DOI: 10.1016/s1473-3099(22)00765-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 11/09/2022] [Accepted: 11/09/2022] [Indexed: 12/24/2022]
Abstract
Administering rectal artesunate suppositories to patients with severe malaria before they receive parenteral and oral consolidation therapy was found to reduce mortality more than a decade ago. The roll-out of rectal artesunate could combat the current global increase in malaria deaths. Instead, on Jan 27, 2022, WHO recommended a moratorium on the deployment of rectal artesunate and in doing so stopped the roll-out of a lifesaving intervention. This decision was based mainly on the results from an observational study that is part of a larger project being conducted in Nigeria, Uganda, and DR Congo. The Community Access to Rectal Artesunate for Malaria (CARAMAL) project was not set up to provide patient transport to referral health-care centres for parenteral artesunate administration or logistic support to assure the availability of parenteral and oral antimalarial consolidation therapy. Using a before-after study design, which is known to be prone to bias, the study found that case fatality rates of severe malaria increased instead of decreased after the roll-out of rectal artesunate. However, the study and its analysis have methodological flaws that provide an alternative explanation for study findings. Instead of further delaying the roll-out of rectal artesunate, there is an urgent need for a concerted effort to provide rectal artesunate as originally intended, where and when it is needed.
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Affiliation(s)
- Lorenz von Seidlein
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand.
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9
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Ombelet S, Natale A, Ronat JB, Vandenberg O, Jacobs J, Hardy L. Considerations in evaluating equipment-free blood culture bottles: A short protocol for use in low-resource settings. PLoS One 2022; 17:e0267491. [PMID: 35468169 PMCID: PMC9037908 DOI: 10.1371/journal.pone.0267491] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 04/07/2022] [Indexed: 12/21/2022] Open
Abstract
Use of equipment-free, “manual” blood cultures is still widespread in low-resource settings, as requirements for implementation of automated systems are often not met. Quality of manual blood culture bottles currently on the market, however, is usually unknown. An acceptable quality in terms of yield and speed of growth can be ensured by evaluating the bottles using simulated blood cultures. In these experiments, bottles from different systems are inoculated in parallel with blood and a known quantity of bacteria. Based on literature review and personal experiences, we propose a short and practical protocol for an efficient evaluation of manual blood culture bottles, aimed at research or reference laboratories in low-resource settings. Recommendations include: (1) practical equivalence of horse blood and human blood; (2) a diverse selection of 10 to 20 micro-organisms to be tested (both slow- and fast-growing reference organisms); (3) evaluation of both adult and pediatric bottle formulations and blood volumes; (4) a minimum sample size of 120 bottles per bottle type; (5) a formal assessment of usability. Different testing scenarios for increasing levels of reliability are provided, along with practical tools such as worksheets and surveys that can be used by laboratories wishing to evaluate manual blood culture bottles.
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Affiliation(s)
- Sien Ombelet
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Immunology & Microbiology Department, KU Leuven, Leuven, Belgium
| | | | - Jean-Baptiste Ronat
- Médecins Sans Frontières, Paris, France
- Team ReSIST, INSERM U1184, School of Medicine University Paris-Saclay, Paris, France
- Bacteriology-Hygiene Unit, Assistance Publique – Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
| | - Olivier Vandenberg
- Center for Environmental Health and Occupational Health, School of Public Health, Université Libre de Bruxelles (ULB), Brussels, Belgium
- Innovation and Business Development Unit, Laboratoire Hospitalier Universitaire de Bruxelles - Universitair Laboratorium Brussel (LHUB-ULB), ULB, Brussels, Belgium
- Division of Infection and Immunity, Faculty of Medical Sciences, University College London, London, United Kingdom
| | - Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Immunology & Microbiology Department, KU Leuven, Leuven, Belgium
| | - Liselotte Hardy
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- * E-mail:
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Nabarro LE, McCann N, Herdman MT, Dugan C, Ladhani S, Patel D, Morris-Jones S, Balasegaram S, Heyderman RS, Brown M, Parry CM, Godbole G. British Infection Association Guidelines for the Diagnosis and Management of Enteric Fever in England. J Infect 2022; 84:469-489. [PMID: 35038438 DOI: 10.1016/j.jinf.2022.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 12/10/2021] [Accepted: 01/05/2022] [Indexed: 11/25/2022]
Abstract
Enteric fever (EF) is an infection caused by the bacteria called Salmonella Typhi or Paratyphi. Infection is acquired through swallowing contaminated food or water. Most EF in England occurs in people returning from South Asia and other places where EF is common; catching EF in England is rare. The main symptom is fever, but stomach pain, diarrhoea, muscle aches, rash and other symptoms may occur. EF is diagnosed by culturing the bacteria from blood and/or stool in a microbiology laboratory. EF usually responds well to antibiotic treatment. Depending on how unwell the individual is, antibiotics may be administered by mouth or by injection. Over the past several years, there has been an overall increase in resistance to antibiotics used to treat enteric fever, in all endemic areas. Additionally, since 2016, there has been an ongoing outbreak of drug-resistant EF in Pakistan. This infection is called extensively drug-resistant, or XDR, EF and only responds to a limited number of antibiotics. Occasionally individuals develop complications of EF including confusion, bleeding, a hole in the gut or an infection of the bones or elsewhere. Some people may continue to carry the bacteria in their stool for a longtime following treatment for the initial illness. These people may need treatment with a longer course of antibiotics to eradicate infection. Travellers can reduce their risk of acquiring EF by following safe food and water practices and by receiving the vaccine at least a few weeks before travel. These guidelines aim to help doctors do the correct tests and treat patients for enteric fever in England but may also be useful to doctors and public health professionals in other similar countries.
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Affiliation(s)
- L E Nabarro
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; United Kingdom Health Security Agency, UK; St George's University Hospitals NHS Foundation Trust, London, UK; British Infection Association, UK
| | - N McCann
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK
| | | | - C Dugan
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK
| | - S Ladhani
- United Kingdom Health Security Agency, UK; Paediatric Infectious Diseases Research Group, St George's University, London, UK
| | - D Patel
- National Travel Health Network and Centre (NaTHNaC), UK
| | - S Morris-Jones
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK
| | | | - R S Heyderman
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Research Department of Infection, Division of Infection and Immunity, University College London, London, UK
| | - M Brown
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
| | - C M Parry
- Liverpool School of Tropical Medicine, Liverpool, UK; Alder Hey Hospital and Liverpool University Hospitals, Liverpool, UK; Centre for Tropical Medicine and Global Health, University of Oxford, UK
| | - G Godbole
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; United Kingdom Health Security Agency, UK; British Infection Association, UK.
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11
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Van Be Bay P, Wain J, Phuong LT, Ho VA, Hien TT, Parry CM. OUP accepted manuscript. Trans R Soc Trop Med Hyg 2022; 116:736-744. [PMID: 35092688 PMCID: PMC9356000 DOI: 10.1093/trstmh/trac003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 11/02/2021] [Accepted: 01/10/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
| | | | - Le Thi Phuong
- Dong Thap Provincial Hospital, Cao Lanh, Dong Thap Province, Vietnam
| | - Vo Anh Ho
- Dong Thap Provincial Hospital, Cao Lanh, Dong Thap Province, Vietnam
| | - Tran Tinh Hien
- Well come Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hospital for Tropical Diseases, 764 Vo Van Kiet, District 5, Ho Chi Minh City, Vietnam
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12
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Forster DP, Leder K. Typhoid fever in travellers: estimating the risk of acquisition by country. J Travel Med 2021; 28:6383558. [PMID: 34619766 PMCID: PMC8715417 DOI: 10.1093/jtm/taab150] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 11/13/2022]
Abstract
BACKGROUND Typhoid fever is a notifiable disease within Australia. Although studies in endemic regions give an indication of acquisition risk, many countries lack reliable data, and little is known of the absolute or relative risk in Australian travellers. By combining notified case data with travel statistics provided by the Australian Bureau of Statistics, the aim of this study was to give an indication of risk for typhoid acquisition among Australian travellers. METHODS Australian typhoid notifications between 1st January 2010 and 30th June 2017 were grouped by country of acquisition and age category (<15 or ≥15 years). Australian travel data were used to inform time at risk and incidence rate of Australian typhoid notifications pertaining to country and region of acquisition. Salmonella Paratyphi infections, though notifiable, were excluded as the focus was vaccine preventable illness. Data from New South Wales and Victoria were used to examine the incidence in those acquiring infection in their country of birth (COB) against travellers who did not. RESULTS Nine hundred twenty-three cases of typhoid were notified over the period of review, 96% of which were acquired overseas. The greatest determinant of risk was travel destination, with countries in south Asia associated with highest crude incidence rate (252 per 100 000 person-years), particularly Bangladesh. Younger age and immigrants returning to their COB were generally associated with higher risk of acquisition. CONCLUSIONS The risk of typhoid fever in Australian travellers to endemic regions is considerable. Immigrants returning to their COB appear to be at higher risk and it is likely that this risk extends to their traveling dependents. These findings help clinicians and public health officials to plan and advise pre-travel vaccination strategies with at-risk individuals and groups. Additional sociodemographic data collection with Australian typhoid notifications would enhance the surveillance of differing international travel risk groups leaving Australia.
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Affiliation(s)
- Daniel P Forster
- Public Events, COVID-19 Response, Engagement & Delivery, Department of Health, VIC, Melbourne, Australia.,Victorian Infectious Diseases Service, Royal Melbourne Hospital at the Doherty Institute for Infection and Immunity, VIC, Melbourne, Australia
| | - Karin Leder
- Victorian Infectious Diseases Service, Royal Melbourne Hospital at the Doherty Institute for Infection and Immunity, VIC, Melbourne, Australia.,School of Public Health and Preventive Medicine, Monash University, VIC, Melbourne, Australia
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13
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Srinivasan M, Sindhu KN, Ramanujam K, Ramasamy RK, Subramaniam S, Ganesan SK, Vajja S, David AS, Lankala P, Rose W, Moses PD, Grassly NC, Kang G, John J. Factors Predicting Blood Culture Positivity in Children With Enteric Fever. J Infect Dis 2021; 224:S484-S493. [PMID: 35238358 PMCID: PMC8892536 DOI: 10.1093/infdis/jiab357] [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] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Blood culture, despite low sensitivity, is the gold standard for enteric fever diagnosis. Understanding predictors of blood culture positivity may help design strategies to optimize enteric fever diagnosis. METHODS A cohort of 6760 children aged 0.5-15 years was followed for 3 years for enteric fever with blood cultures in an automated system, for fevers >3 days. Factors affecting test positivity in fevers and participant-level predictors for culture refusals were analyzed using regression models. RESULTS Overall, 6097 suspected typhoid/paratyphoid fever (STF) episodes were reported, of which 5703 (93.5%) STFs had sampling for blood cultures, with 394 (6.5%) refusals. Salmonella enterica serovar Typhi/Paratyphi positivity was culture-confirmed in 3.8% (218/5703) of STF episodes. Older children (odds ratio [OR], 1.96 [95% CI, 1.39-2.77]), larger blood volume inoculated (OR, 2.82 [95% CI, 1.71-4.66]), higher temperatures during fever (OR, 3.77 [95% CI, 2.89-4.91]), and fevers diagnosed as suspected typhoid or acute undifferentiated fever (OR, 6.06 [95% CI, 3.11-11.78]) had a higher probability of culture positivity. Antibiotics before culture did not decrease culture positivity. Blood culture refusals were higher for children from wealthier households or with milder illness. CONCLUSIONS Performing blood cultures in older children with fever, especially those fevers with toxic presentation and increasing blood volume for inoculation are strategies to improve enteric fever detection in surveillance settings.
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Affiliation(s)
- Manikandan Srinivasan
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | | | - Karthikeyan Ramanujam
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Ranjith Kumar Ramasamy
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Sathyapriya Subramaniam
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Santhosh Kumar Ganesan
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Swathi Vajja
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Anita Shirley David
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Pramitha Lankala
- Department of Community Health, Christian Medical College, Vellore, India
| | - Winsley Rose
- Wellcome Trust Research Laboratory, Division of Gastrointestinal Sciences, Christian Medical College, Vellore, India
| | - Prabhakar D Moses
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Nicholas C Grassly
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Gagandeep Kang
- Division of Gastrointestinal Sciences, Wellcome Trust Research Laboratory, Christian Medical College, Vellore, India
| | - Jacob John
- Department of Community Health, Christian Medical College, Vellore, India,Correspondence: Jacob John, MD, PhD, Department of Community Health, Christian Medical College, Vellore, Tamil Nadu 632 004, India ()
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14
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Giri A, Karkey A, Dongol S, Arjyal A, Maharjan A, Veeraraghavan B, Paudyal B, Dolecek C, Gajurel D, Phuong DNT, Thanh DP, Qamar F, Kang G, Hien HV, John J, Lawson K, Wolbers M, Hossain MS, Sharifuzzaman M, Luangasanatip N, Maharjan N, Olliaro P, Rupali P, Shakya R, Shakoor S, Rijal S, Qureshi S, Baker S, Joshi S, Ahmed T, Darton T, Bao TN, Lubell Y, Kestelyn E, Thwaites G, Parry CM, Basnyat B. Azithromycin and cefixime combination versus azithromycin alone for the out-patient treatment of clinically suspected or confirmed uncomplicated typhoid fever in South Asia: a randomised controlled trial protocol. Wellcome Open Res 2021; 6:207. [PMID: 35097222 PMCID: PMC8772527 DOI: 10.12688/wellcomeopenres.16801.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2021] [Indexed: 12/03/2022] Open
Abstract
Background: Typhoid and paratyphoid fever (enteric fever) is a common cause of non-specific febrile infection in adults and children presenting to health care facilities in low resource settings such as the South Asia. A 7-day course of a single oral antimicrobial such as ciprofloxacin, cefixime, or azithromycin is commonly used for its treatment. Increasing antimicrobial resistance threatens the effectiveness of these treatment choices. We hypothesize that combined treatment with azithromycin (active mainly intracellularly) and cefixime (active mainly extracellularly) will be a better option for the treatment of clinically suspected and culture-confirmed typhoid fever in South Asia. Methods: This is a phase IV, international multi-center, multi-country, comparative participant-and observer-blind, 1:1 randomised clinical trial. Patients with suspected uncomplicated typhoid fever will be randomized to one of the two interventions: Arm A: azithromycin 20mg/kg/day oral dose once daily (maximum 1gm/day) and cefixime 20mg/kg/day oral dose in two divided doses (maximum 400mg bd) for 7 days, Arm B: azithromycin 20mg/kg/day oral dose once daily (max 1gm/day) for 7 days AND cefixime-matched placebo for 7 days. We will recruit 1500 patients across sites in Bangladesh, India, Nepal, and Pakistan. We will assess whether treatment outcomes are better with the combination after one week of treatment and at one- and three-months follow-up. Discussion: Combined treatment may limit the emergence of resistance if one of the components is active against resistant sub-populations not covered by the other antimicrobial activity. If the combined treatment is better than the single antimicrobial treatment, this will be an important result for patients across South Asia and other typhoid endemic areas. Clinicaltrials.gov registration: NCT04349826 (16/04/2020)
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Affiliation(s)
- Abhishek Giri
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Abhilasha Karkey
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sabina Dongol
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Amit Arjyal
- Patan Academy of Health Sciences, Lalitpur, Bagmati, 44700, Nepal
| | - Archana Maharjan
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | | | - Buddhi Paudyal
- Patan Academy of Health Sciences, Lalitpur, Bagmati, 44700, Nepal
| | - Christiane Dolecek
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | | | - Duy Pham Thanh
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Farah Qamar
- Aga Khan University Hospital, Karachi, 74800, Pakistan
| | - Gagandeep Kang
- Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Ho Van Hien
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Jacob John
- Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Katrina Lawson
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Marcel Wolbers
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Md. Shabab Hossain
- International Centre for Diarrhoeal Disease Research (icddr, b), Dhaka, Bangladesh
| | - M Sharifuzzaman
- International Centre for Diarrhoeal Disease Research (icddr, b), Dhaka, Bangladesh
| | | | - Nhukesh Maharjan
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Piero Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Ronas Shakya
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Sadia Shakoor
- Aga Khan University Hospital, Karachi, 74800, Pakistan
| | - Samita Rijal
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Sonia Qureshi
- Aga Khan University Hospital, Karachi, 74800, Pakistan
| | - Stephen Baker
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Subi Joshi
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Tahmeed Ahmed
- International Centre for Diarrhoeal Disease Research (icddr, b), Dhaka, Bangladesh
| | - Thomas Darton
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, South Yorkshire, UK
| | - Tran Nguyen Bao
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Yoel Lubell
- Mahidol Oxford Tropical Medicine Research Unit (MORU), Bangkok, 10400, Thailand
| | - Evelyne Kestelyn
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Guy Thwaites
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Christopher M. Parry
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Buddha Basnyat
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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15
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Giri A, Karkey A, Dongol S, Arjyal A, Maharjan A, Veeraraghavan B, Paudyal B, Dolecek C, Gajurel D, Phuong DNT, Thanh DP, Qamar F, Kang G, Hien HV, John J, Lawson K, Wolbers M, Hossain MS, Sharifuzzaman M, Luangasanatip N, Maharjan N, Olliaro P, Rupali P, Shakya R, Shakoor S, Rijal S, Qureshi S, Baker S, Joshi S, Ahmed T, Darton T, Bao TN, Lubell Y, Kestelyn E, Thwaites G, Parry CM, Basnyat B. Azithromycin and cefixime combination versus azithromycin alone for the out-patient treatment of clinically suspected or confirmed uncomplicated typhoid fever in South Asia: a randomised controlled trial protocol. Wellcome Open Res 2021; 6:207. [PMID: 35097222 PMCID: PMC8772527 DOI: 10.12688/wellcomeopenres.16801.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2021] [Indexed: 12/27/2023] Open
Abstract
Background: Typhoid and paratyphoid fever (enteric fever) is a common cause of non-specific febrile infection in adults and children presenting to health care facilities in low resource settings such as the South Asia. A 7-day course of a single oral antimicrobial such as ciprofloxacin, cefixime, or azithromycin is commonly used for its treatment. Increasing antimicrobial resistance threatens the effectiveness of these treatment choices. We hypothesize that combined treatment with azithromycin (active mainly intracellularly) and cefixime (active mainly extracellularly) will be a better option for the treatment of clinically suspected and culture-confirmed typhoid fever in South Asia. Methods: This is a phase IV, international multi-center, multi-country, comparative participant-and observer-blind, 1:1 randomised clinical trial. Patients with suspected uncomplicated typhoid fever will be randomized to one of the two interventions: Arm A: azithromycin 20mg/kg/day oral dose once daily (maximum 1gm/day) and cefixime 20mg/kg/day oral dose in two divided doses (maximum 400mg bd) for 7 days, Arm B: azithromycin 20mg/kg/day oral dose once daily (max 1gm/day) for 7 days AND cefixime-matched placebo for 7 days. We will recruit 1500 patients across sites in Bangladesh, India, Nepal, and Pakistan. We will assess whether treatment outcomes are better with the combination after one week of treatment and at one- and three-months follow-up. Discussion: Combined treatment may limit the emergence of resistance if one of the components is active against resistant sub-populations not covered by the other antimicrobial activity. If the combined treatment is better than the single antimicrobial treatment, this will be an important result for patients across South Asia and other typhoid endemic areas. Clinicaltrials.gov registration: NCT04349826 (16/04/2020).
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Affiliation(s)
- Abhishek Giri
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Abhilasha Karkey
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Sabina Dongol
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Amit Arjyal
- Patan Academy of Health Sciences, Lalitpur, Bagmati, 44700, Nepal
| | - Archana Maharjan
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | | | - Buddhi Paudyal
- Patan Academy of Health Sciences, Lalitpur, Bagmati, 44700, Nepal
| | - Christiane Dolecek
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | | | - Duy Pham Thanh
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Farah Qamar
- Aga Khan University Hospital, Karachi, 74800, Pakistan
| | - Gagandeep Kang
- Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Ho Van Hien
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Jacob John
- Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Katrina Lawson
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Marcel Wolbers
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Md. Shabab Hossain
- International Centre for Diarrhoeal Disease Research (icddr, b), Dhaka, Bangladesh
| | - M Sharifuzzaman
- International Centre for Diarrhoeal Disease Research (icddr, b), Dhaka, Bangladesh
| | | | - Nhukesh Maharjan
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Piero Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Ronas Shakya
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Sadia Shakoor
- Aga Khan University Hospital, Karachi, 74800, Pakistan
| | - Samita Rijal
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Sonia Qureshi
- Aga Khan University Hospital, Karachi, 74800, Pakistan
| | - Stephen Baker
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Subi Joshi
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
| | - Tahmeed Ahmed
- International Centre for Diarrhoeal Disease Research (icddr, b), Dhaka, Bangladesh
| | - Thomas Darton
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, South Yorkshire, UK
| | - Tran Nguyen Bao
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Yoel Lubell
- Mahidol Oxford Tropical Medicine Research Unit (MORU), Bangkok, 10400, Thailand
| | - Evelyne Kestelyn
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Guy Thwaites
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Christopher M. Parry
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Buddha Basnyat
- Oxford University Clinical Research Unit-Nepal, Patan Academy of Health Scineces, Lalitpur, Bagmati, 44700, Nepal
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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16
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Wilairatana P, Mala W, Klangbud WK, Kotepui KU, Rattaprasert P, Kotepui M. Prevalence, probability, and outcomes of typhoidal/non-typhoidal Salmonella and malaria co-infection among febrile patients: a systematic review and meta-analysis. Sci Rep 2021; 11:21889. [PMID: 34750425 PMCID: PMC8576030 DOI: 10.1038/s41598-021-00611-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/14/2021] [Indexed: 11/09/2022] Open
Abstract
The geographical overlaps of malaria parasites and Salmonella spp. can lead to co-infection of these two pathogens, especially in the tropics where malaria is endemic. Moreover, few literatures suggested that malaria infection was associated with Salmonella bacteremia. Therefore, this study quantified pooled prevalence of typhoidal/non-typhoidal Salmonella (NTS) and probability of typhoidal/NTS and malaria co-infection among febrile patients. The systematic review protocol was registered at PROSPERO (CRD42021252322). Studies on co-infection of typhoidal/NTS and malaria were searched in PubMed, Scopus, and Web of Science. The risk of bias of the included studies was assessed using the checklist for analytical cross-sectional studies developed by the Joanna Briggs Institute. Meta-analyses on the following criteria were performed: (1) pooled prevalence of typhoidal/NTS and malaria co-infection among febrile patients, (2) pooled prevalence of typhoidal/NTS among malaria patients, (3) pooled prevalence of malaria infections among patients with Salmonella spp. infection, and (4) probability of typhoidal/NTS and malaria co-infection among febrile patients. Additionally, the case fatality rate and mean difference of malarial parasitemia between typhoidal/NTS and malaria co-infection and Plasmodium monoinfection were also determined. The subgroup analyses of typhoidal/NTS, regions (Africa and Asia), countries, time (publication year), characteristics of participants, and diagnostic tests for identifying Salmonella spp. were also conducted. A sensitivity test was performed to determine the robustness of the study outcomes. Publication bias among the included studies was evaluated using the funnel plot and Egger’s test. All analyses were performed using Stata version 15 (StataCorp LLC, Texas, USA) with a p-value < 0.05 indicating statistical significance. Eighty-one studies that met the eligibility criteria were included in the analyses. Of the 73,775 study participants, 4523 had typhoidal/NTS and malaria co-infections. The pooled prevalence rates of typhoidal/NTS and malaria co-infection among febrile patients were 14% (95% confidence interval [CI], 9–19%; I2, 99.4%; 2971/17,720 cases) and 1% (95% CI 1–1%; I2, 89.9%; 252/29,081 cases) using the Widal test and culture methods for identifying Salmonella spp., respectively. The pooled prevalence rates of typhoidal/NTS infection among patients with malaria were 31% (95% CI 23–39%; I2, 99.5%; 3202/19,208 cases) and 3% (95% CI 2–3%; I2, 86.8%; 407/40,426 cases) using the Widal test and culture methods for identifying Salmonella spp., respectively. The pooled prevalence rates of malaria infection among patients with typhoidal/NTS were 17% (95% CI 6–29%; I2, 33.3%; 13/75 cases) and 43% (95% CI 32–53%; I2, 89.1%; 287/736 cases), respectively. Malaria infection was associated with typhoidal/NTS in children aged < 15 years (p < 0.0001; odds ratio, 0.36; 95% CI 0.23–0.58; I2, 73.9%; 3188/43,212 cases). The case fatality rate in patients with malaria and NTS co-infections was 16% (95% CI 9–24%; I2, 89.1%; 18/103 cases). From the view of the present study, the inappropriate use of the Widal test for Salmonella spp. diagnosis can overestimate the prevalence of typhoidal/NTS and malaria co-infections. Malaria infection associated with typhoidal/NTS in children and the high case fatality rates among few patients with co-infections were highlighted. Future prospective longitudinal studies using the appropriate and confirmatory dsiagnosis for Salmonella spp. infections are highly recommended to ensure the real prevalence of co-infection and highlight the outcome of co-infection for providing adequate treatment in febrile patients who live in areas where malaria is endemic, such as tropical Africa and India.
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Affiliation(s)
- Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Wanida Mala
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Wiyada Kwanhian Klangbud
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Kwuntida Uthaisar Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Pongruj Rattaprasert
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Manas Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand.
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Abstract
Highlights (1) Blood culture is the gold standard for the diagnosis of bacterial infections. (2) Bone marrow culture is more sensitive than blood culture even in patients with enteric fever receiving antibiotics. (3) Microscopic agglutination test is considered the gold standard for diagnosing leptospirosis; however, now IgM ELISA and polymerase chain reaction (PCR) are more frequently used for diagnosis. (4) Tuberculosis is diagnosed with the help of nucleic acid amplification tests like Xpert MTB/RIF Ultra which also detects rifampicin resistance. Other tests include microscopy, Lowenstein-Jensen and mycobacteria growth indicator tube culture, line probe assay. (5) Tropical rickettsial infections are diagnosed by serological reactions (Weil-Felix, ELISA for antibodies) and PCR. (6) For Brucellosis culture from blood, bone marrow or tissue specimens remain the mainstay in diagnosis. (7) Dengue, Zika, Crimean-Congo hemorrhagic fever, Ebola, hantavirus, rabies are diagnosed with reverse transcriptase-polymerase chain reaction. Serological tests like IgM ELISA or paired sera samples for IgG are also used for diagnosis. How to cite this article Basu S, Shetty A. Laboratory Diagnosis of Tropical Infections. Indian J Crit Care Med 2021;25(Suppl 2):S122-S126.
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Affiliation(s)
- Shaoli Basu
- Department of Microbiology, PD Hinduja Hospital, Mumbai, Maharashtra, India
| | - Anjali Shetty
- Department of Microbiology, PD Hinduja Hospital, Mumbai, Maharashtra, India
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Zahid I, Sarwar A, Hussain A, Sohail M, Amin A. Antibiotyping and genotyping of extensively drug-resistant (XDR) Salmonella sp. isolated from clinical samples of Lahore, Pakistan. J Appl Microbiol 2021; 132:633-641. [PMID: 33969606 DOI: 10.1111/jam.15131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 04/12/2021] [Accepted: 04/30/2021] [Indexed: 11/30/2022]
Abstract
AIMS Antibiotic resistance is a major problem in Salmonella enterica serovar Typhi. The objective of this study was to evaluate the prevalence of XDR Salmonella among local population of Lahore and genotyping of isolates for antibiotic-resistant genes. METHODS AND RESULTS A total of 200 blood samples from suspected typhoid fever patients were collected. One hundred and fifty-seven bacterial samples were confirmed as Salmonella Typhi and 23 samples were confirmed as Salmonella Paratyphi after biochemical, serological and PCR based molecular characterization. Antibiogram analysis classified 121 (67·2%) Salmonella isolates as MDR and 62 isolates (34·4%) as XDR. The predominant resistance gene was ampC with 47·7% prevalence, followed by gyrA, catA1, tet(A), aac (3)-la, qnrS, blaNDM-1 and blaCTX-M-15 genes in 45·5, 40, 21·6, 18·3, 11·6, 2·2 and 0·5% isolates respectively. Sequence analysis showed the presence of sul1 and dfrA7 gene cassette arrays in 12 class 1 integron integrase positive isolates. CONCLUSION Large number of clinical XDR S. Typhi-resistant against third generation cephalosporins have been reported. SIGNIFICANCE AND IMPACT OF THE STUDY The current study highlights the possible emergence of clinical XDR S. Typhi cases in Lahore, Pakistan. Potential attribution of phenotypic and genotypic XDR cases may help to contribute targeted therapy.
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Affiliation(s)
- Iqra Zahid
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
| | - Arslan Sarwar
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
| | - Abid Hussain
- Department of Medical Lab Technology, Faculty of Rehabilitation & Allied Health Sciences, Riphah International University Islamabad, QIE Campus, Lahore, Pakistan
| | - Muhammad Sohail
- Department of Medical Lab Technology, Faculty of Rehabilitation & Allied Health Sciences, Riphah International University Islamabad, QIE Campus, Lahore, Pakistan
| | - Aatif Amin
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
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19
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The Brief Case: Salmonella enterica Serovar Typhi in a Central American Refugee. J Clin Microbiol 2021; 59:59/5/e01359-20. [PMID: 33879561 DOI: 10.1128/jcm.01359-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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20
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Enteric Fever Diagnosis: Current Challenges and Future Directions. Pathogens 2021; 10:pathogens10040410. [PMID: 33915749 PMCID: PMC8065732 DOI: 10.3390/pathogens10040410] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/23/2021] [Accepted: 03/27/2021] [Indexed: 12/21/2022] Open
Abstract
Enteric fever is a life-threatening systemic febrile disease caused by Salmonella enterica serovars Typhi and Paratyphi (S. Typhi and S. Paratyphi). Unfortunately, the burden of the disease remains high primarily due to the global spread of various drug-resistant Salmonella strains despite continuous advancement in the field. An accurate diagnosis is critical for effective control of the disease. However, enteric fever diagnosis based on clinical presentations is challenging due to overlapping symptoms with other febrile illnesses that are also prevalent in endemic areas. Current laboratory tests display suboptimal sensitivity and specificity, and no diagnostic methods are available for identifying asymptomatic carriers. Several research programs have employed systemic approaches to identify more specific biomarkers for early detection and asymptomatic carrier detection. This review discusses the pros and cons of currently available diagnostic tests for enteric fever, the advancement of research toward improved diagnostic tests, and the challenges of discovering new ideal biomarkers and tests.
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21
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Alhaj-Qasem DM, Al-Hatamleh MAI, Irekeola AA, Khalid MF, Mohamud R, Ismail A, Mustafa FH. Laboratory Diagnosis of Paratyphoid Fever: Opportunity of Surface Plasmon Resonance. Diagnostics (Basel) 2020; 10:diagnostics10070438. [PMID: 32605310 PMCID: PMC7400347 DOI: 10.3390/diagnostics10070438] [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: 05/29/2020] [Revised: 06/18/2020] [Accepted: 06/25/2020] [Indexed: 12/19/2022] Open
Abstract
Paratyphoid fever is caused by the bacterium Salmonellaenterica serovar Paratyphi (A, B and C), and contributes significantly to global disease burden. One of the major challenges in the diagnosis of paratyphoid fever is the lack of a proper gold standard. Given the absence of a licensed vaccine against S. Paratyphi, this diagnostic gap leads to inappropriate antibiotics use, thus, enhancing antimicrobial resistance. In addition, the symptoms of paratyphoid overlap with other infections, including the closely related typhoid fever. Since the development and utilization of a standard, sensitive, and accurate diagnostic method is essential in controlling any disease, this review discusses a new promising approach to aid the diagnosis of paratyphoid fever. This advocated approach is based on the use of surface plasmon resonance (SPR) biosensor and DNA probes to detect specific nucleic acid sequences of S. Paratyphi. We believe that this SPR-based genoassay can be a potent alternative to the current conventional diagnostic methods, and could become a rapid diagnostic tool for paratyphoid fever.
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Affiliation(s)
| | - Mohammad A. I. Al-Hatamleh
- Department of Immunology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia; (M.A.I.A.-H.); (R.M.)
| | - Ahmad Adebayo Irekeola
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia;
- Microbiology Unit, Department of Biological Sciences, College of Natural and Applied Sciences, Summit University Offa, Offa PMB 4412, Kwara State, Nigeria
| | - Muhammad Fazli Khalid
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia; (M.F.K.); (A.I.)
| | - Rohimah Mohamud
- Department of Immunology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia; (M.A.I.A.-H.); (R.M.)
- Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia
| | - Aziah Ismail
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia; (M.F.K.); (A.I.)
| | - Fatin Hamimi Mustafa
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Kubang Kerian, Kelantan 16150, Malaysia; (M.F.K.); (A.I.)
- Correspondence: ; Tel.: +60-9767-2432
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Pouzol S, Tanmoy AM, Ahmed D, Khanam F, Brooks WA, Bhuyan GS, Fabre L, Bryant JE, Gustin MP, Vanhems P, Carman B, Weill FX, Qadri F, Saha S, Endtz H. Clinical Evaluation of a Multiplex PCR for the Detection of Salmonella enterica Serovars Typhi and Paratyphi A from Blood Specimens in a High-Endemic Setting. Am J Trop Med Hyg 2020; 101:513-520. [PMID: 31287048 PMCID: PMC6726943 DOI: 10.4269/ajtmh.18-0992] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Enteric fever is a major public health concern in endemic areas, particularly in infrastructure-limited countries where Salmonella Paratyphi A has emerged in increasing proportion of cases. We aimed to evaluate a method to detect Salmonella Typhi (S. Typhi) and Salmonella Paratyphi A (S. Paratyphi A) in febrile patients in Bangladesh. We conducted a prospective study enrolling patients with fever > 38°C admitted to two large urban hospitals and two outpatient clinics located in Dhaka, Bangladesh. We developed and evaluated a method combining short culture with a new molecular assay to simultaneously detect and differentiate S. Typhi and S. Paratyphi A from other Salmonella directly from 2 to 4 mL of whole blood in febrile patients (n = 680). A total of 680 cases were enrolled from the four participating sites. An increase in the detection rate (+38.8%) in S. Typhi and S. Paratyphi A was observed with a multiplex polymerase chain reaction (PCR) assay, and absence of non-typhoidal Salmonella detection was reported. All 45 healthy controls were culture and PCR negative, generating an estimated 92.9% of specificity on clinical samples. When clinical performance was assessed in the absence of blood volume prioritization for testing, a latent class model estimates clinical performance ≥ 95% in sensitivity and specificity with likelihood ratio (LR) LR+ > 10 and LR− < 0.1 for the multiplex PCR assay. The alternative method to blood culture we developed may be useful alone or in combination with culture or serological tests for epidemiological studies in high disease burden settings and should be considered as secondary endpoint test for future vaccine trials.
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Affiliation(s)
- Stephane Pouzol
- Laboratoire des Pathogènes Emergents, Fondation Mérieux, Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Arif Mohammad Tanmoy
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, The Netherlands.,Child Health Research Foundation (CHRF), Dhaka, Bangladesh
| | - Dilruba Ahmed
- International Centre for Diarrhoeal Disease Research (icddr,b), Dhaka, Bangladesh
| | - Farhana Khanam
- International Centre for Diarrhoeal Disease Research (icddr,b), Dhaka, Bangladesh
| | - W Abdullah Brooks
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland
| | - Golam Sarower Bhuyan
- Institute for Developing Science and Health Initiatives (ideSHi), Dhaka, Bangladesh
| | - Laetitia Fabre
- Unité des Bactéries Pathogènes Entériques, Institut Pasteur, Paris, France
| | - Juliet E Bryant
- Laboratoire des Pathogènes Emergents, Fondation Mérieux, Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Marie-Paule Gustin
- Department of Public Health, Institute of Pharmacy, University of Lyon 1, Lyon, France.,Laboratoire des Pathogènes Emergents, Fondation Mérieux, Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Philippe Vanhems
- Service d'Hygiène, Epidémiologie et Prévention, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France.,Laboratoire des Pathogènes Emergents, Fondation Mérieux, Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Bill Carman
- Fast Track Diagnostics, Esch sur alzette, Esch-sur-Alzette, Luxembourg
| | | | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research (icddr,b), Dhaka, Bangladesh
| | - Samir Saha
- Child Health Research Foundation (CHRF), Dhaka, Bangladesh
| | - Hubert Endtz
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, The Netherlands.,Laboratoire des Pathogènes Emergents, Fondation Mérieux, Centre International de Recherche en Infectiologie (CIRI), Lyon, France
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Sai SK, Padhi S, Varghese RGB, Kanungo R, Basheer A, Iqbal N. Diagnostic utility of bone marrow examination in evaluation of fever: a descriptive study on 98 immunocompetent adults from a tertiary care institute in south India. Trop Doct 2019; 49:88-96. [PMID: 30614411 DOI: 10.1177/0049475518822844] [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: 11/17/2022]
Abstract
Five-year clinico-laboratory data from 99 (one HIV seropositive) adults (mean age = 41.3 ± 20.4 years) who underwent bone marrow examination for fever persisting for ≥ 1 week were analysed and correlated with microbiological characteristics. Infections, reactive marrow changes and haematolymphoid malignancies were most commonly associated with fever. A high concordance rate of 71% was noted between aspiration and trephine biopsies. Bone marrow granulomas (BMG) were seen exclusively on sections and were most commonly of tubercular and typhoidal in origin (two Salmonella Typhi, one Salmonella Paratyphi A). The common aetiologies associated with fever and cytopenia(s) were BMG, acute leukaemia and haemophagocytic lymphohistiocytosis (HLH; n = 3). The yield from bone marrow culture was inferior compared to other body fluids. In conclusion, bone marrow histology is superior to smears in the evaluation of prolonged fever. Marrow culture may not be useful in immunocompetent individuals other than if Salmonellosis is suspected.
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Affiliation(s)
- Sri Krishna Sai
- 1 Junior Resident, Department of Pathology, Pondicherry Institute of Medical Sciences, Pondicherry, India
| | - Somanath Padhi
- 2 Associate Professor, Department of Pathology, Pondicherry Institute of Medical Sciences, Pondicherry, India
| | - Renu G Boy Varghese
- 3 Professor and Head, Department of Pathology, Pondicherry Institute of Medical Sciences, Pondicherry, India
| | - Reba Kanungo
- 4 Professor and Head, Department of Microbiology, Pondicherry Institute of Medical Sciences, Pondicherry, India
| | - Aneesh Basheer
- 5 Associate Professor, Department of General Medicine, Pondicherry Institute of Medical Sciences, Pondicherry, India
| | - Nayyar Iqbal
- 5 Associate Professor, Department of General Medicine, Pondicherry Institute of Medical Sciences, Pondicherry, India
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Gal-Mor O. Persistent Infection and Long-Term Carriage of Typhoidal and Nontyphoidal Salmonellae. Clin Microbiol Rev 2019; 32:e00088-18. [PMID: 30487167 PMCID: PMC6302356 DOI: 10.1128/cmr.00088-18] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The ability of pathogenic bacteria to affect higher organisms and cause disease is one of the most dramatic properties of microorganisms. Some pathogens can establish transient colonization only, but others are capable of infecting their host for many years or even for a lifetime. Long-term infection is called persistence, and this phenotype is fundamental for the biology of important human pathogens, including Helicobacter pylori, Mycobacterium tuberculosis, and Salmonella enterica Both typhoidal and nontyphoidal serovars of the species Salmonella enterica can cause persistent infection in humans; however, as these two Salmonella groups cause clinically distinct diseases, the characteristics of their persistent infections in humans differ significantly. Here, following a general summary of Salmonella pathogenicity, host specificity, epidemiology, and laboratory diagnosis, I review the current knowledge about Salmonella persistence and discuss the relevant epidemiology of persistence (including carrier rate, duration of shedding, and host and pathogen risk factors), the host response to Salmonella persistence, Salmonella genes involved in this lifestyle, as well as genetic and phenotypic changes acquired during prolonged infection within the host. Additionally, I highlight differences between the persistence of typhoidal and nontyphoidal Salmonella strains in humans and summarize the current gaps and limitations in our understanding, diagnosis, and curing of persistent Salmonella infections.
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Affiliation(s)
- Ohad Gal-Mor
- Infectious Diseases Research Laboratory, Sheba Medical Center, Tel-Hashomer, Israel
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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Dash HR, Das S. Microbial Degradation of Forensic Samples of Biological Origin: Potential Threat to Human DNA Typing. Mol Biotechnol 2018; 60:141-153. [PMID: 29214499 DOI: 10.1007/s12033-017-0052-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Forensic biology is a sub-discipline of biological science with an amalgam of other branches of science used in the criminal justice system. Any nucleated cell/tissue harbouring DNA, either live or dead, can be used as forensic exhibits, a source of investigation through DNA typing. These biological materials of human origin are rich source of proteins, carbohydrates, lipids, trace elements as well as water and, thus, provide a virtuous milieu for the growth of microbes. The obstinate microbial growth augments the degradation process and is amplified with the passage of time and improper storage of the biological materials. Degradation of these biological materials carriages a huge challenge in the downstream processes of forensic DNA typing technique, such as short tandem repeats (STR) DNA typing. Microbial degradation yields improper or no PCR amplification, heterozygous peak imbalance, DNA contamination from non-human sources, degradation of DNA by microbial by-products, etc. Consequently, the most precise STR DNA typing technique is nullified and definite opinion can be hardly given with degraded forensic exhibits. Thus, suitable precautionary measures should be taken for proper storage and processing of the biological exhibits to minimize their decaying process by micro-organisms.
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Affiliation(s)
- Hirak Ranjan Dash
- DNA Fingerprinting Unit, State Forensic Science Laboratory, Sagar, Madhya Pradesh, 470001, India
| | - Surajit Das
- Department of Life Science, Laboratory of Environmental Microbiology and Ecology (LEnME), National Institute of Technology, Rourkela, Odisha, 769008, India.
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Yaseen MM, Abuharfeil NM, Yaseen MM, Shabsoug BM. The role of polymorphonuclear neutrophils during HIV-1 infection. Arch Virol 2017; 163:1-21. [PMID: 28980078 DOI: 10.1007/s00705-017-3569-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 08/14/2017] [Indexed: 12/23/2022]
Abstract
It is well-recognized that human immunodeficiency virus type-1 (HIV-1) mainly targets CD4+ T cells and macrophages. Nonetheless, during the past three decades, a huge number of studies have reported that HIV-1 can directly or indirectly target other cellular components of the immune system including CD8+ T cells, B cells, dendritic cells, natural killer cells, and polymorphonuclear neutrophils (PMNs), among others. PMNs are the most abundant leukocytes in the human circulation, and are known to play principal roles in the elimination of invading pathogens, regulating different immune responses, healing of injured tissues, and maintaining mucosal homeostasis. Until recently, little was known about the impact of HIV-1 infection on PMNs as well as the impact of PMNs on HIV-1 disease progression. This is because early studies focused on neutropenia and recurrent microbial infections, particularly, during advanced disease. However, recent studies have extended the investigation area to cover new aspects of the interactions between HIV-1 and PMNs. This review aims to summarize these advances and address the impact of HIV-1 infection on PMNs as well as the impact of PMNs on HIV-1 disease progression to better understand the pathophysiology of HIV-1 infection.
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Affiliation(s)
- Mahmoud Mohammad Yaseen
- Medical Laboratory Sciences, College of Applied Medical Sciences, Jordan University of Science and Technology, Irbid, 22110, Jordan.
| | - Nizar Mohammad Abuharfeil
- Applied Biological Sciences, College of Science and Arts, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Mohammad Mahmoud Yaseen
- Public Health, College of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Barakat Mohammad Shabsoug
- Chemical Sciences, College of Science and Arts, Jordan University of Science and Technology, Irbid, 22110, Jordan
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Kuijpers LMF, Phe T, Veng CH, Lim K, Ieng S, Kham C, Fawal N, Fabre L, Le Hello S, Vlieghe E, Weill FX, Jacobs J, Peetermans WE. The clinical and microbiological characteristics of enteric fever in Cambodia, 2008-2015. PLoS Negl Trop Dis 2017; 11:e0005964. [PMID: 28931025 PMCID: PMC5624643 DOI: 10.1371/journal.pntd.0005964] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 10/02/2017] [Accepted: 09/14/2017] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Enteric fever remains a major public health problem in low resource settings and antibiotic resistance is increasing. In Asia, an increasing proportion of infections is caused by Salmonella enterica serovar Paratyphi A, which for a long time was assumed to cause a milder clinical syndrome compared to Salmonella enterica serovar Typhi. METHODOLOGY A retrospective chart review study was conducted of 254 unique cases of blood culture confirmed enteric fever who presented at a referral adult hospital in Phnom Penh, Cambodia between 2008 and 2015. Demographic, clinical and laboratory data were collected from clinical charts and antibiotic susceptibility testing was performed. Whole genome sequence analysis was performed on a subset of 121 isolates. RESULTS One-hundred-and-ninety unique patients were diagnosed with Salmonella Paratyphi A and 64 with Salmonella Typhi. In the period 2008-2012, Salmonella Paratyphi A comprised 25.5% of 47 enteric fever cases compared to 86.0% of 207 cases during 2013-2015. Presenting symptoms were identical for both serovars but higher median leukocyte counts (6.8 x 109/L vs. 6.3 x 109/L; p = 0.035) and C-reactive protein (CRP) values (47.0 mg/L vs. 36 mg/L; p = 0.034) were observed for Salmonella Typhi infections. All but one of the Salmonella Typhi isolates belonged to haplotype H58 associated with multidrug resistance (MDR) (i.e. resistance to ampicillin, chloramphenicol and co-trimoxazole).;42.9% actually displayed MDR compared to none of the Salmonella Paratyphi A isolates. Decreased ciprofloxacin susceptibility (DCS) was observed in 96.9% (62/64) of Salmonella Typhi isolates versus 11.5% (21/183) of Salmonella Paratyphi A isolates (all but one from 2015). All isolates were susceptible to azithromycin and ceftriaxone. CONCLUSIONS In Phnom Penh, Cambodia, Salmonella Paratyphi A now causes the majority of enteric fever cases and decreased susceptibility against ciprofloxacin is increasing. Overall, Salmonella Typhi was significantly more associated with MDR and DCS compared to Salmonella Paratyphi A.
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Affiliation(s)
- Laura M. F. Kuijpers
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Microbiology & Immunology, KU Leuven, Leuven, Belgium
- * E-mail:
| | - Thong Phe
- Sihanouk Hospital Center of HOPE, Phnom Penh, Cambodia
| | - Chhun H. Veng
- Sihanouk Hospital Center of HOPE, Phnom Penh, Cambodia
| | - Kruy Lim
- Sihanouk Hospital Center of HOPE, Phnom Penh, Cambodia
| | - Sovann Ieng
- Sihanouk Hospital Center of HOPE, Phnom Penh, Cambodia
| | - Chun Kham
- Sihanouk Hospital Center of HOPE, Phnom Penh, Cambodia
| | - Nizar Fawal
- Unité des Bactéries Pathogènes Entériques, Centre National de Référence des E. coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Laetitia Fabre
- Unité des Bactéries Pathogènes Entériques, Centre National de Référence des E. coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Simon Le Hello
- Unité des Bactéries Pathogènes Entériques, Centre National de Référence des E. coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Erika Vlieghe
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of General Internal Medicine, Infectious diseases and Tropical Medicine, University Hospital Antwerp, Antwerp, Belgium
| | - François-Xavier Weill
- Unité des Bactéries Pathogènes Entériques, Centre National de Référence des E. coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Jan Jacobs
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Microbiology & Immunology, KU Leuven, Leuven, Belgium
| | - Willy E. Peetermans
- Department of Internal Medicine, University Hospital Leuven, Leuven, Belgium
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Abstract
BACKGROUND Differentiating both typhoid (Salmonella Typhi) and paratyphoid (Salmonella Paratyphi A) infection from other causes of fever in endemic areas is a diagnostic challenge. Although commercial point-of-care rapid diagnostic tests (RDTs) for enteric fever are available as alternatives to the current reference standard test of blood or bone marrow culture, or to the widely used Widal Test, their diagnostic accuracy is unclear. If accurate, they could potentially replace blood culture as the World Health Organization (WHO)-recommended main diagnostic test for enteric fever. OBJECTIVES To assess the diagnostic accuracy of commercially available rapid diagnostic tests (RDTs) and prototypes for detecting Salmonella Typhi or Paratyphi A infection in symptomatic persons living in endemic areas. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, IndMED, African Index Medicus, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) up to 4 March 2016. We manually searched WHO reports, and papers from international conferences on Salmonella infections. We also contacted test manufacturers to identify studies. SELECTION CRITERIA We included diagnostic accuracy studies of enteric fever RDTs in patients with fever or with symptoms suggestive of enteric fever living in endemic areas. We classified the reference standard used as either Grade 1 (result from a blood culture and a bone marrow culture) or Grade 2 (result from blood culture and blood polymerase chain reaction, or from blood culture alone). DATA COLLECTION AND ANALYSIS Two review authors independently extracted the test result data. We used a modified QUADAS-2 extraction form to assess methodological quality. We performed a meta-analysis when there were sufficient studies for the test and heterogeneity was reasonable. MAIN RESULTS Thirty-seven studies met the inclusion criteria and included a total of 5080 participants (range 50 to 1732). Enteric fever prevalence rates in the study populations ranged from 1% to 75% (median prevalence 24%, interquartile range (IQR) 11% to 46%). The included studies evaluated 16 different RDTs, and 16 studies compared two or more different RDTs. Only three studies used the Grade 1 reference standard, and only 11 studies recruited unselected febrile patients. Most included studies were from Asia, with five studies from sub-Saharan Africa. All of the RDTs were designed to detect S.Typhi infection only.Most studies evaluated three RDTs and their variants: TUBEX in 14 studies; Typhidot (Typhidot, Typhidot-M, and TyphiRapid-Tr02) in 22 studies; and the Test-It Typhoid immunochromatographic lateral flow assay, and its earlier prototypes (dipstick, latex agglutination) developed by the Royal Tropical Institute, Amsterdam (KIT) in nine studies. Meta-analyses showed an average sensitivity of 78% (95% confidence interval (CI) 71% to 85%) and specificity of 87% (95% CI 82% to 91%) for TUBEX; and an average sensitivity of 69% (95% CI 59% to 78%) and specificity of 90% (95% CI 78% to 93%) for all Test-It Typhoid and prototype tests (KIT). Across all forms of the Typhidot test, the average sensitivity was 84% (95% CI 73% to 91%) and specificity was 79% (95% CI 70% to 87%). When we based the analysis on the 13 studies of the Typhidot test that either reported indeterminate test results or where the test format means there are no indeterminate results, the average sensitivity was 78% (95% CI 65% to 87%) and specificity was 77% (95% CI 66% to 86%). We did not identify any difference in either sensitivity or specificity between TUBEX, Typhidot, and Test-it Typhoid tests when based on comparison to the 13 Typhidot studies where indeterminate results are either reported or not applicable. If TUBEX and Test-it Typhoid are compared to all Typhidot studies, the sensitivity of Typhidot was higher than Test-it Typhoid (15% (95% CI 2% to 28%), but other comparisons did not show a difference at the 95% level of CIs.In a hypothetical cohort of 1000 patients presenting with fever where 30% (300 patients) have enteric fever, on average Typhidot tests reporting indeterminate results or where tests do not produce indeterminate results will miss the diagnosis in 66 patients with enteric fever, TUBEX will miss 66, and Test-It Typhoid and prototype (KIT) tests will miss 93. In the 700 people without enteric fever, the number of people incorrectly diagnosed with enteric fever would be 161 with Typhidot tests, 91 with TUBEX, and 70 with Test-It Typhoid and prototype (KIT) tests. The CIs around these estimates were wide, with no difference in false positive results shown between tests.The quality of the data for each study was evaluated using a standardized checklist called QUADAS-2. Overall, the certainty of the evidence in the studies that evaluated enteric fever RDTs was low. AUTHORS' CONCLUSIONS In 37 studies that evaluated the diagnostic accuracy of RDTs for enteric fever, few studies were at a low risk of bias. The three main RDT tests and variants had moderate diagnostic accuracy. There was no evidence of a difference between the average sensitivity and specificity of the three main RDT tests. More robust evaluations of alternative RDTs for enteric fever are needed.
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Affiliation(s)
- Lalith Wijedoru
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolUKL3 5QA
| | - Sue Mallett
- University of BirminghamInstitute of Applied Health SciencesEdgbastonBirminghamUKB15 2TT
| | - Christopher M Parry
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesLiverpoolUKL3 5QA
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Tran Vu Thieu N, Trinh Van T, Tran Tuan A, Klemm EJ, Nguyen Ngoc Minh C, Voong Vinh P, Pham Thanh D, Ho Ngoc Dan T, Pham Duc T, Langat P, Martin LB, Galan J, Liang L, Felgner PL, Davies DH, de Jong HK, Maude RR, Fukushima M, Wijedoru L, Ghose A, Samad R, Dondorp AM, Faiz A, Darton TC, Pollard AJ, Thwaites GE, Dougan G, Parry CM, Baker S. An evaluation of purified Salmonella Typhi protein antigens for the serological diagnosis of acute typhoid fever. J Infect 2017; 75:104-114. [PMID: 28551371 PMCID: PMC5522525 DOI: 10.1016/j.jinf.2017.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 05/15/2017] [Accepted: 05/16/2017] [Indexed: 12/14/2022]
Abstract
Objectives The diagnosis of typhoid fever is a challenge. Aiming to develop a typhoid diagnostic we measured antibody responses against Salmonella Typhi (S. Typhi) protein antigens and the Vi polysaccharide in a cohort of Bangladeshi febrile patients. Methods IgM against 12 purified antigens and the Vi polysaccharide was measured by ELISA in plasma from patients with confirmed typhoid fever (n = 32), other confirmed infections (n = 17), and healthy controls (n = 40). ELISAs with the most specific antigens were performed on plasma from 243 patients with undiagnosed febrile disease. Results IgM against the S. Typhi protein antigens correlated with each other (rho > 0.8), but not against Vi (rho < 0.6). Typhoid patients exhibited higher IgM against 11/12 protein antigens and Vi than healthy controls and those with other infections. Vi, PilL, and CdtB exhibited the greatest sensitivity and specificity. Specificity and sensitivity was improved when Vi was combined with a protein antigen, generating sensitivities and specificities of 0.80 and >0.85, respectively. Applying a dynamic cut-off to patients with undiagnosed febrile disease suggested that 34–58% had an IgM response indicative of typhoid. Conclusions We evaluated the diagnostic potential of several S. Typhi antigens; our assays give good sensitivity and specificity, but require further assessment in differing patient populations.
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Affiliation(s)
- Nga Tran Vu Thieu
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Tan Trinh Van
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Anh Tran Tuan
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Elizabeth J Klemm
- The Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Chau Nguyen Ngoc Minh
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Phat Voong Vinh
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Duy Pham Thanh
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Thanh Ho Ngoc Dan
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Trung Pham Duc
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Pinky Langat
- The Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire, United Kingdom
| | - Laura B Martin
- Sclavo Berhing Vaccines Institute for Global Health, Siena, Italy
| | - Jorge Galan
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Li Liang
- Department of Medicine, Division of Infectious Diseases, University of California, Irvine, CA, USA
| | - Philip L Felgner
- Department of Medicine, Division of Infectious Diseases, University of California, Irvine, CA, USA
| | - D Huw Davies
- Department of Medicine, Division of Infectious Diseases, University of California, Irvine, CA, USA
| | - Hanna K de Jong
- Department of Internal Medicine, Division of Infectious Diseases and Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Rapeephan R Maude
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Oxford University, Oxford, United Kingdom
| | - Masako Fukushima
- Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Lalith Wijedoru
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Rasheda Samad
- Chittagong Medical College Hospital, Chittagong, Bangladesh
| | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Malaria Research Group and Dev Care Foundation, Bangladesh
| | - Abul Faiz
- Malaria Research Group and Dev Care Foundation, Bangladesh
| | - Thomas C Darton
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Sheffield Teaching Hospitals NHS Trust Foundation and the University of Sheffield, Sheffield, United Kingdom
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Guy E Thwaites
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Centre for Tropical Medicine and Global Health, Oxford University, Oxford, United Kingdom
| | - Gordon Dougan
- The Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire, United Kingdom; The Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Christopher M Parry
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Stephen Baker
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Centre for Tropical Medicine and Global Health, Oxford University, Oxford, United Kingdom; The Department of Medicine, University of Cambridge, Cambridge, United Kingdom.
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Prabagaran SR, Kalaiselvi V, Chandramouleeswaran N, Deepthi KNG, Brahmadathan KN, Mani M. Molecular diagnosis of Salmonella typhi and its virulence in suspected typhoid blood samples through nested multiplex PCR. J Microbiol Methods 2017; 139:150-154. [PMID: 28545919 DOI: 10.1016/j.mimet.2017.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/19/2017] [Accepted: 05/22/2017] [Indexed: 10/19/2022]
Abstract
A nested multiplex polymerase chain reaction (PCR) based diagnosis was developed for the detection of virulent Salmonella typhi in the blood specimens from patients suspected for typhoid fever. After the Widal test, two pairs of primers were used for the detection of flagellin gene (fliC) of S. typhi. Among them, those positive for fliC alone were subjected to identification of genes in Via B operon of Salmonella Pathogenesity Island (SPI-7) where four primer pairs were used to detect tviA and tviB genes. Among 250 blood samples tested, 115 were positive by fliC PCR; 22 of these were negative for tviA and tviB. Hence, the method described here can be used to diagnose the incidence of Vi-negative serovar typhi especially in endemic regions where the Vi vaccine is administered.
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Affiliation(s)
| | - Vellingiri Kalaiselvi
- Department of Biotechnology, Bharathiar University, Coimbatore, Tamilnadu 641 046, India
| | | | | | | | - Mariappa Mani
- Microbiological Laboratory, Cowley Brown Road (East), R. S. Puram, Coimbatore- 641 002, India
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Darton TC, Zhou L, Blohmke CJ, Jones C, Waddington CS, Baker S, Pollard AJ. Blood culture-PCR to optimise typhoid fever diagnosis after controlled human infection identifies frequent asymptomatic cases and evidence of primary bacteraemia. J Infect 2017; 74:358-366. [PMID: 28130144 PMCID: PMC5345565 DOI: 10.1016/j.jinf.2017.01.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/11/2017] [Accepted: 01/14/2017] [Indexed: 01/09/2023]
Abstract
Background Improved diagnostics for typhoid are needed; a typhoid controlled human infection model may accelerate their development and translation. Here, we evaluated a blood culture-PCR assay for detecting infection after controlled human infection with S. Typhi and compared test performance with optimally performed blood cultures. Methodology/Principal findings Culture-PCR amplification of blood samples was performed alongside daily blood culture in 41 participants undergoing typhoid challenge. Study endpoints for typhoid diagnosis (TD) were fever and/or bacteraemia. Overall, 24/41 (59%) participants reached TD, of whom 21/24 (86%) had ≥1 positive blood culture (53/674, 7.9% of all cultures) or 18/24 (75%) had ≥1 positive culture-PCR assay result (57/684, 8.3%). A further five non-bacteraemic participants produced culture-PCR amplicons indicating infection; overall sensitivity/specificity of the assay compared to the study endpoints were 70%/65%. We found no significant difference between blood culture and culture-PCR methods in ability to identify cases (12 mismatching pairs, p = 0.77, binomial test). Clinical and stool culture metadata demonstrated that additional culture-PCR amplification positive individuals likely represented true cases missed by blood culture, suggesting the overall attack rate may be 30/41 (73%) rather than 24/41 (59%). Several participants had positive culture-PCR results soon after ingesting challenge providing new evidence for occurrence of an early primary bacteraemia. Conclusions/Significance Overall the culture-PCR assay performed well, identifying extra typhoid cases compared with routine blood culture alone. Despite limitations to widespread field-use, the benefits of increased diagnostic yield, reduced blood volume and faster turn-around-time, suggest that this assay could enhance laboratory typhoid diagnostics in research applications and high-incidence settings. Culture in ox-bile/tryptone soy broth selectively enriches for bile-tolerant Salmonella Typhi while lysing human cells. PCR sensitivity for detecting typhoid in clinical blood is limited by very low level bacteraemia during clinical illness. PCR amplification of S. Typhi fliC-d in pre-cultured blood can accurately identify typhoid infection in challenge study participants. Daily culture-PCR of blood collected from challenge study participants suggests primary bacteraemia occurs 12–36 h after S. Typhi ingestion. Additional use of culture-PCR demonstrates the true attack rate after typhoid challenge is markedly higher (75%) than previously assumed (60%).
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Affiliation(s)
- Thomas C Darton
- Oxford Vaccine Group, Department of Paediatrics and the NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom; The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam.
| | - Liqing Zhou
- Oxford Vaccine Group, Department of Paediatrics and the NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Christoph J Blohmke
- Oxford Vaccine Group, Department of Paediatrics and the NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Claire Jones
- Oxford Vaccine Group, Department of Paediatrics and the NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Claire S Waddington
- Oxford Vaccine Group, Department of Paediatrics and the NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
| | - Stephen Baker
- The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Oxford University, Oxford, United Kingdom
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics and the NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, United Kingdom
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Nanotheranostic approaches for management of bloodstream bacterial infections. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2017; 13:329-341. [DOI: 10.1016/j.nano.2016.09.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 08/30/2016] [Accepted: 09/16/2016] [Indexed: 12/14/2022]
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von Kalckreuth V, Konings F, Aaby P, Adu-Sarkodie Y, Ali M, Aseffa A, Baker S, Breiman RF, Bjerregaard-Andersen M, Clemens JD, Crump JA, Cruz Espinoza LM, Deerin JF, Gasmelseed N, Sow AG, Im J, Keddy KH, Cosmas L, May J, Meyer CG, Mintz ED, Montgomery JM, Olack B, Pak GD, Panzner U, Park SE, Rakotozandrindrainy R, Schütt-Gerowitt H, Soura AB, Warren MR, Wierzba TF, Marks F. The Typhoid Fever Surveillance in Africa Program (TSAP): Clinical, Diagnostic, and Epidemiological Methodologies. Clin Infect Dis 2016; 62 Suppl 1:S9-S16. [PMID: 26933028 DOI: 10.1093/cid/civ693] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND New immunization programs are dependent on data from surveillance networks and disease burden estimates to prioritize target areas and risk groups. Data regarding invasive Salmonella disease in sub-Saharan Africa are currently limited, thus hindering the implementation of preventive measures. The Typhoid Fever Surveillance in Africa Program (TSAP) was established by the International Vaccine Institute to obtain comparable incidence data on typhoid fever and invasive nontyphoidal Salmonella (iNTS) disease in sub-Saharan Africa through standardized surveillance in multiple countries. METHODS Standardized procedures were developed and deployed across sites for study site selection, patient enrolment, laboratory procedures, quality control and quality assurance, assessment of healthcare utilization and incidence calculations. RESULTS Passive surveillance for bloodstream infections among febrile patients was initiated at thirteen sentinel sites in ten countries (Burkina Faso, Ethiopia, Ghana, Guinea-Bissau, Kenya, Madagascar, Senegal, South Africa, Sudan, and Tanzania). Each TSAP site conducted case detection using these standardized methods to isolate and identify aerobic bacteria from the bloodstream of febrile patients. Healthcare utilization surveys were conducted to adjust population denominators in incidence calculations for differing healthcare utilization patterns and improve comparability of incidence rates across sites. CONCLUSIONS By providing standardized data on the incidence of typhoid fever and iNTS disease in sub-Saharan Africa, TSAP will provide vital input for targeted typhoid fever prevention programs.
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Affiliation(s)
| | - Frank Konings
- International Vaccine Institute, Seoul, Republic of Korea
| | - Peter Aaby
- Bandim Health Project, Bissau, Guinea-Bissau
| | - Yaw Adu-Sarkodie
- Kumasi Centre for Collaborative Research in Tropical Medicine School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Mohammad Ali
- International Vaccine Institute, Seoul, Republic of Korea Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Stephen Baker
- Oxford University Clinical Resarch Unit, Ho Chi Minh City, Vietnam
| | - Robert F Breiman
- Centers for Disease Control and Prevention, Nairobi, Kenya Global Health Institute, Emory University, Atlanta, Georgia
| | | | - John D Clemens
- International Vaccine Institute, Seoul, Republic of Korea International Centre for Diarrheal Disease Research, Dhaka, Bangladesh
| | - John A Crump
- Division of Infectious Diseases and International Health, Duke University Medical Center Duke Global Health Institute, Duke University, Durham, North Carolina Kilimanjaro Christian Medical Centre, Moshi, Tanzania Centre for International Health, University of Otago, Dunedin, New Zealand
| | | | | | | | - Amy Gassama Sow
- Institute Pasteur Senegal Université Cheikh Anta Diop de Dakar, Senegal
| | - Justin Im
- International Vaccine Institute, Seoul, Republic of Korea
| | - Karen H Keddy
- National Institute for Communicable Diseases School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Leonard Cosmas
- Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Jürgen May
- Department of Infection Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg
| | - Christian G Meyer
- Institute of Tropical Medicine, Eberhard-Karls University Tübingen, Germany
| | - Eric D Mintz
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | | | - Gi Deok Pak
- International Vaccine Institute, Seoul, Republic of Korea
| | - Ursula Panzner
- International Vaccine Institute, Seoul, Republic of Korea
| | - Se Eun Park
- International Vaccine Institute, Seoul, Republic of Korea
| | | | | | | | | | | | - Florian Marks
- International Vaccine Institute, Seoul, Republic of Korea
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Galen JE, Buskirk AD, Tennant SM, Pasetti MF. Live Attenuated Human Salmonella Vaccine Candidates: Tracking the Pathogen in Natural Infection and Stimulation of Host Immunity. EcoSal Plus 2016; 7:10.1128/ecosalplus.ESP-0010-2016. [PMID: 27809955 PMCID: PMC5119766 DOI: 10.1128/ecosalplus.esp-0010-2016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Indexed: 04/08/2023]
Abstract
Salmonellosis, caused by members of the genus Salmonella, is responsible for considerable global morbidity and mortality in both animals and humans. In this review, we will discuss the pathogenesis of Salmonella enterica serovar Typhi and Salmonella enterica serovar Typhimurium, focusing on human Salmonella infections. We will trace the path of Salmonella through the body, including host entry sites, tissues and organs affected, and mechanisms involved in both pathogenesis and stimulation of host immunity. Careful consideration of the natural progression of disease provides an important context in which attenuated live oral vaccines can be rationally designed and developed. With this in mind, we will describe a series of attenuated live oral vaccines that have been successfully tested in clinical trials and demonstrated to be both safe and highly immunogenic. The attenuation strategies summarized in this review offer important insights into further development of attenuated vaccines against other Salmonella for which live oral candidates are currently unavailable.
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Affiliation(s)
- James E. Galen
- Center for Vaccine Development, Institute for Global Health, University of Maryland School of Medicine, Baltimore MD 21201
- Division of Geographic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore MD 21201
| | - Amanda D. Buskirk
- Center for Vaccine Development, Institute for Global Health, University of Maryland School of Medicine, Baltimore MD 21201
- Division of Infectious Diseases and Tropical Pediatrics, Department of Pediatrics, University of Maryland School of Medicine, Baltimore MD 21201
| | - Sharon M. Tennant
- Center for Vaccine Development, Institute for Global Health, University of Maryland School of Medicine, Baltimore MD 21201
- Division of Geographic Medicine, Department of Medicine, University of Maryland School of Medicine, Baltimore MD 21201
| | - Marcela F. Pasetti
- Center for Vaccine Development, Institute for Global Health, University of Maryland School of Medicine, Baltimore MD 21201
- Division of Infectious Diseases and Tropical Pediatrics, Department of Pediatrics, University of Maryland School of Medicine, Baltimore MD 21201
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Nichols C, Cruz Espinoza LM, von Kalckreuth V, Aaby P, Ahmed El Tayeb M, Ali M, Aseffa A, Bjerregaard-Andersen M, Breiman RF, Cosmas L, Crump JA, Dekker DM, Gassama Sow A, Gasmelseed N, Hertz JT, Im J, Kabore LP, Keddy KH, Konings F, Valborg Løfberg S, Meyer CG, Montgomery JM, Niang A, Njariharinjakamampionona A, Olack B, Pak GD, Panzner U, Park JK, Park SE, Rabezanahary H, Rakotondrainiarivelo JP, Rakotozandrindrainy R, Raminosoa TM, Rubach MP, Teferi M, Seo HJ, Sooka A, Soura A, Tall A, Toy T, Yeshitela B, Clemens JD, Wierzba TF, Baker S, Marks F. Bloodstream Infections and Frequency of Pretreatment Associated With Age and Hospitalization Status in Sub-Saharan Africa. Clin Infect Dis 2016; 61 Suppl 4:S372-9. [PMID: 26449954 DOI: 10.1093/cid/civ730] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The clinical diagnosis of bacterial bloodstream infections (BSIs) in sub-Saharan Africa is routinely confused with malaria due to overlapping symptoms. The Typhoid Surveillance in Africa Program (TSAP) recruited febrile inpatients and outpatients of all ages using identical study procedures and enrollment criteria, thus providing an opportunity to assess disease etiology and pretreatment patterns among children and adults. METHODS Inpatients and outpatients of all ages with tympanic or axillary temperatures of ≥38.0 or ≥37.5°C, respectively, and inpatients only reporting fever within the previous 72 hours were eligible for recruitment. All recruited patients had one blood sample drawn and cultured for microorganisms. Data from 11 TSAP surveillance sites in nine different countries were used in the analysis. Bivariate analysis was used to compare frequencies of pretreatment and BSIs in febrile children (<15 years old) and adults (≥15 years old) in each country. Pooled Cochran Mantel-Haenszel odds ratios (ORs) were calculated for overall trends. RESULTS There was no significant difference in the odds of a culture-proven BSI between children and adults among inpatients or outpatients. Among both inpatients and outpatients, children had significantly higher odds of having a contaminated blood culture compared with adults. Using country-pooled data, child outpatients had 66% higher odds of having Salmonella Typhi in their bloodstream than adults (OR, 1.66; 95% confidence interval [CI], 1.01-2.73). Overall, inpatient children had 59% higher odds of pretreatment with analgesics in comparison to inpatient adults (OR, 1.59; 95% CI, 1.28-1.97). CONCLUSIONS The proportion of patients with culture-proven BSIs in children compared with adults was similar across the TSAP study population; however, outpatient children were more likely to have Salmonella Typhi infections than outpatient adults. This finding points to the importance of including outpatient facilities in surveillance efforts, particularly for the surveillance of typhoid fever. Strategies to reduce contamination among pediatric blood cultures are needed across the continent to prevent the misdiagnosis of BSI cases in children.
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Affiliation(s)
| | | | | | - Peter Aaby
- Bandim Health Project, Bissau, Guinea-Bissau Research Center for Vitamins and Vaccines, Copenhagen, Denmark
| | | | - Mohammad Ali
- International Vaccine Institute, Seoul, Republic of Korea Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | | | - Robert F Breiman
- Kenya Medical Research Institute-Center for Global Health Research, Nairobi Global Health Institute, Emory University, Atlanta, Georgia
| | - Leonard Cosmas
- Kenya Medical Research Institute-Center for Global Health Research, Nairobi Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention-Kenya, Nairobi
| | - John A Crump
- Division of Infectious Diseases and International Health, Duke University Medical Center Duke Global Health Institute, Duke University, Durham, North Carolina Centre for International Health, University of Otago, Dunedin, New Zealand Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | | | - Amy Gassama Sow
- Université Cheikh Anta Diop de Dakar Institut Pasteur de Dakar, Senegal
| | | | - Julian T Hertz
- Division of Infectious Diseases and International Health, Duke University Medical Center Duke Global Health Institute, Duke University, Durham, North Carolina
| | - Justin Im
- International Vaccine Institute, Seoul, Republic of Korea
| | | | - Karen H Keddy
- National Institute for Communicable Diseases Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Frank Konings
- International Vaccine Institute, Seoul, Republic of Korea
| | - Sandra Valborg Løfberg
- Bandim Health Project, Bissau, Guinea-Bissau Research Center for Vitamins and Vaccines, Copenhagen, Denmark
| | - Christian G Meyer
- Institute of Tropical Medicine, Eberhard-Karls University Tübingen, Germany
| | - Joel M Montgomery
- Kenya Medical Research Institute-Center for Global Health Research, Nairobi Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention-Kenya, Nairobi
| | | | | | - Beatrice Olack
- Kenya Medical Research Institute-Center for Global Health Research, Nairobi
| | - Gi Deok Pak
- International Vaccine Institute, Seoul, Republic of Korea
| | - Ursula Panzner
- International Vaccine Institute, Seoul, Republic of Korea
| | - Jin Kyung Park
- International Vaccine Institute, Seoul, Republic of Korea
| | - Se Eun Park
- International Vaccine Institute, Seoul, Republic of Korea
| | | | | | | | | | - Matthew P Rubach
- Division of Infectious Diseases and International Health, Duke University Medical Center
| | | | - Hye Jin Seo
- International Vaccine Institute, Seoul, Republic of Korea
| | | | - Abdramane Soura
- Institut Supérieur des Sciences de la Population, University of Ouagadougou, Burkina Faso
| | | | - Trevor Toy
- International Vaccine Institute, Seoul, Republic of Korea
| | | | - John D Clemens
- International Centre for Diarrheal Disease Research, Bangladesh, Dhaka UCLA Fielding School of Public Health
| | | | - Stephen Baker
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Florian Marks
- International Vaccine Institute, Seoul, Republic of Korea
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Tennant SM, Toema D, Qamar F, Iqbal N, Boyd MA, Marshall JM, Blackwelder WC, Wu Y, Quadri F, Khan A, Aziz F, Ahmad K, Kalam A, Asif E, Qureshi S, Khan E, Zaidi AK, Levine MM. Detection of Typhoidal and Paratyphoidal Salmonella in Blood by Real-time Polymerase Chain Reaction. Clin Infect Dis 2016; 61 Suppl 4:S241-50. [PMID: 26449938 DOI: 10.1093/cid/civ726] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The gold standard for diagnosis of enteric fever caused by Salmonella Typhi or Salmonella Paratyphi A or B is bone marrow culture. However, because bone marrow aspiration is highly invasive, many hospitals and large health centers perform blood culture instead. As blood culture has several limitations, there is a need for novel typhoid diagnostics with improved sensitivity and more rapid time to detection. METHODS We developed a clyA-based real-time polymerase chain reaction (qPCR) method to detect Salmonella Typhi and Salmonella Paratyphi A simultaneously in blood. The sensitivity and specificity of this probeset was first evaluated in vitro in the laboratory and then in a typhoid-endemic population, in Karachi, Pakistan, and in healthy US volunteers. RESULTS We optimized a DNA extraction and real-time PCR-based method that could reliably detect 1 colony-forming unit/mL of Salmonella Typhi. The probe set was able to detect clinical Salmonella Typhi and Salmonella Paratyphi A strains and also diarrheagenic Escherichia coli, but not invasive E. coli or other invasive bacteria. In the field, the clyA qPCR diagnostic was 40% as sensitive as blood culture. However, when qPCR-positive specimens were considered to be true positives, blood culture only exhibited 28.57% sensitivity. Specificity was ≥90% for all comparisons and in the healthy US volunteers. qPCR was significantly faster than blood culture in terms of detection of typhoid and paratyphoid. CONCLUSIONS Based on lessons learned, we recommend that future field trials of this and other novel diagnostics that detect typhoidal and nontyphoidal Salmonella employ multiple methodologies to define a "positive" sample.
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Affiliation(s)
- Sharon M Tennant
- Center for Vaccine Development Department of Medicine, University of Maryland, Baltimore
| | - Deanna Toema
- Center for Vaccine Development Department of Medicine, University of Maryland, Baltimore
| | | | - Najeeha Iqbal
- Department of Paediatrics and Child Health Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Mary Adetinuke Boyd
- Center for Vaccine Development Department of Pediatrics, University of Maryland, Baltimore
| | - Joanna M Marshall
- Center for Vaccine Development Department of Medicine, University of Maryland, Baltimore
| | - William C Blackwelder
- Center for Vaccine Development Department of Medicine, University of Maryland, Baltimore
| | - Yukun Wu
- Center for Vaccine Development Department of Medicine, University of Maryland, Baltimore
| | | | - Asia Khan
- Department of Paediatrics and Child Health
| | | | | | - Adil Kalam
- Department of Paediatrics and Child Health
| | | | | | - Erum Khan
- Department of Pathology and Microbiology, Aga Khan University, Karachi, Pakistan
| | | | - Myron M Levine
- Center for Vaccine Development Department of Medicine, University of Maryland, Baltimore Department of Pediatrics, University of Maryland, Baltimore
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Mogasale V, Ramani E, Mogasale VV, Park J. What proportion of Salmonella Typhi cases are detected by blood culture? A systematic literature review. Ann Clin Microbiol Antimicrob 2016; 15:32. [PMID: 27188991 PMCID: PMC4869319 DOI: 10.1186/s12941-016-0147-z] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 05/09/2016] [Indexed: 12/29/2022] Open
Abstract
Blood culture is often used in definitive diagnosis of typhoid fever while, bone marrow culture has a greater sensitivity and considered reference standard. The sensitivity of blood culture measured against bone marrow culture results in measurement bias because both tests are not fully sensitive. Here we propose a combination of the two cultures as a reference to define true positive S. Typhi cases. Based on a systematic literature review, we identified ten papers that had performed blood and bone marrow culture for S. Typhi in same subjects. We estimated the weighted mean of proportion of cases detected by culture measured against true S. Typhi positive cases using a random effects model. Of 529 true positive S. Typhi cases, 61 % (95 % CI 52–70 %) and 96 % (95 % CI 93–99 %) were detected by blood and bone marrow cultures respectively. Blood culture sensitivity was 66 % (95 % CI 56–75 %) when compared with bone marrow culture results. The use of blood culture sensitivity as a proxy measure to estimate the proportion of typhoid fever cases detected by blood culture is likely to be an underestimate. As blood culture sensitivity is used as a correction factor in estimating typhoid disease burden, epidemiologists and policy makers should account for the underestimation.
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Affiliation(s)
- Vittal Mogasale
- Policy and Economic Research Department, Development and Delivery Unit, International Vaccine Institute, Seoul, Republic of Korea.
| | - Enusa Ramani
- Policy and Economic Research Department, Development and Delivery Unit, International Vaccine Institute, Seoul, Republic of Korea
| | - Vijayalaxmi V Mogasale
- Epidemiology Department, Development and Delivery Unit, International Vaccine Institute, Seoul, Republic of Korea
| | - JuYeon Park
- Biostatistics and Data Management Department, Development and Delivery Unit, International Vaccine Institute, Seoul, Republic of Korea
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Zhou L, Jones C, Gibani MM, Dobinson H, Thomaides-Brears H, Shrestha S, Blohmke CJ, Darton TC, Pollard AJ. Development and Evaluation of a Blood Culture PCR Assay for Rapid Detection of Salmonella Paratyphi A in Clinical Samples. PLoS One 2016; 11:e0150576. [PMID: 26930553 PMCID: PMC4773247 DOI: 10.1371/journal.pone.0150576] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 02/17/2016] [Indexed: 01/15/2023] Open
Abstract
Background Enteric fever remains an important cause of morbidity in many low-income countries and Salmonella Paratyphi A has emerged as the aetiological agent in an increasing proportion of cases. Lack of adequate diagnostics hinders early diagnosis and prompt treatment of both typhoid and paratyphoid but development of assays to identify paratyphoid has been particularly neglected. Here we describe the development of a rapid and sensitive blood culture PCR method for detection of Salmonella Paratyphi A from blood, potentially allowing for appropriate diagnosis and antimicrobial treatment to be initiated on the same day. Methods Venous blood samples from volunteers experimentally challenged orally with Salmonella Paratyphi A, who subsequently developed paratyphoid, were taken on the day of diagnosis; 10 ml for quantitative blood culture and automated blood culture, and 5 ml for blood culture PCR. In the latter assay, bacteria were grown in tryptone soy broth containing 2.4% ox bile and micrococcal nuclease for 5 hours (37°C) before bacterial DNA was isolated for PCR detection targeting the fliC-a gene of Salmonella Paratyphi A. Results An optimized broth containing 2.4% ox bile and micrococcal nuclease, as well as a PCR test was developed for a blood culture PCR assay of Salmonella Paratyphi A. The volunteers diagnosed with paratyphoid had a median bacterial burden of 1 (range 0.1–6.9) CFU/ml blood. All the blood culture PCR positive cases where a positive bacterial growth was shown by quantitative blood culture had a bacterial burden of ≥ 0.3 CFU/ ml blood. The blood culture PCR assay identified an equal number of positive cases as automated blood culture at higher bacterial loads (≥0.3 CFU/ml blood), but utilized only half the volume of specimens. Conclusions The blood culture PCR method for detection of Salmonella Paratyphi A can be completed within 9 hours and offers the potential for same-day diagnosis of enteric fever. Using 5 ml blood, it exhibited a lower limit of detection equal to 0.3 CFU/ml blood, and it performed at least as well as automated blood culture at higher bacterial loads (≥0.3 CFU/ml blood) of clinical specimens despite using half the volume of blood. The findings warrant its further study in endemic populations with a potential use as a novel diagnostic which fills the present gap of paratyphoid diagnostics.
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Affiliation(s)
- Liqing Zhou
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
- * E-mail:
| | - Claire Jones
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Malick M. Gibani
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Hazel Dobinson
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Helena Thomaides-Brears
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Sonu Shrestha
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Christoph J. Blohmke
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Thomas C. Darton
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Andrew J. Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
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Al-Emran HM, Hahn A, Baum J, Cruz Espinoza LM, Deerin J, Im J, Ibrango S, Kabore LP, von Kalckreuth V, Konings F, Marks F, Sampo E, Panzner U, Park SE, Pak GD, Schütt-Gerowitt H, Vinnemeier CD, Warren M, Soura AB. DiagnosingSalmonella entericaSerovar Typhi Infections by Polymerase Chain Reaction Using EDTA Blood Samples of Febrile Patients From Burkina Faso. Clin Infect Dis 2016; 62 Suppl 1:S37-41. [DOI: 10.1093/cid/civ770] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Storey HL, Huang Y, Crudder C, Golden A, de los Santos T, Hawkins K. A Meta-Analysis of Typhoid Diagnostic Accuracy Studies: A Recommendation to Adopt a Standardized Composite Reference. PLoS One 2015; 10:e0142364. [PMID: 26566275 PMCID: PMC4643909 DOI: 10.1371/journal.pone.0142364] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/21/2015] [Indexed: 01/09/2023] Open
Abstract
Novel typhoid diagnostics currently under development have the potential to improve clinical care, surveillance, and the disease burden estimates that support vaccine introduction. Blood culture is most often used as the reference method to evaluate the accuracy of new typhoid tests; however, it is recognized to be an imperfect gold standard. If no single gold standard test exists, use of a composite reference standard (CRS) can improve estimation of diagnostic accuracy. Numerous studies have used a CRS to evaluate new typhoid diagnostics; however, there is no consensus on an appropriate CRS. In order to evaluate existing tests for use as a reference test or inclusion in a CRS, we performed a systematic review of the typhoid literature to include all index/reference test combinations observed. We described the landscape of comparisons performed, showed results of a meta-analysis on the accuracy of the more common combinations, and evaluated sources of variability based on study quality. This wide-ranging meta-analysis suggests that no single test has sufficiently good performance but some existing diagnostics may be useful as part of a CRS. Additionally, based on findings from the meta-analysis and a constructed numerical example demonstrating the use of CRS, we proposed necessary criteria and potential components of a typhoid CRS to guide future recommendations. Agreement and adoption by all investigators of a standardized CRS is requisite, and would improve comparison of new diagnostics across independent studies, leading to the identification of a better reference test and improved confidence in prevalence estimates.
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Affiliation(s)
- Helen L. Storey
- Diagnostics Program, PATH, Seattle, Washington, United States of America
- * E-mail:
| | - Ying Huang
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Chris Crudder
- Diagnostics Program, PATH, Seattle, Washington, United States of America
| | - Allison Golden
- Diagnostics Program, PATH, Seattle, Washington, United States of America
| | - Tala de los Santos
- Diagnostics Program, PATH, Seattle, Washington, United States of America
| | - Kenneth Hawkins
- Diagnostics Program, PATH, Seattle, Washington, United States of America
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Abstract
Salmonella enterica is a leading cause of community-acquired bloodstream infection in Africa. The contribution of typhoidal and nontyphoidal Salmonella serovars to invasive disease varies considerably in place and time, even within the same country. Nonetheless, many African countries are now thought to experience typhoid fever incidence >100 per 100,000 per year with approximately 1% of patients dying. Invasive nontyphoidal Salmonella (iNTS) disease was estimated to cause 3.4 million illnesses and 681 316 deaths in 2010, with the most disease in Africa. Antimicrobial drug resistance is a growing problem in S. enterica that threatens to further compromise patient outcomes. Reservoirs for nontyphoidal Salmonella and the predominant routes of transmission for typhoidal and nontyphoidal Salmonella are not well understood in Africa, hampering the design of evidence-based, non-vaccine- and vaccine-based prevention measures. It is difficult to distinguish clinically invasive Salmonella disease from febrile illnesses caused by other pathogens. Blood cultures are the mainstay of laboratory diagnosis, but lack sensitivity due to the low magnitude of bacteremia, do not produce results at point of care, and are not widely available in Africa. Serologic approaches to diagnosis remain inaccurate, and nucleic acid amplification tests are also compromised by low concentrations of bacteria. High-throughput whole-genome sequencing, together with a range of novel analytic pipelines, has provided new insights into the complex pattern of epidemiology, pathogenesis, and host adaptation. Concerted efforts are therefore needed to apply these new tools in the context of high-quality field surveillance to improve diagnosis, patient management, control, and prevention of invasive Salmonella infections in Africa.
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Affiliation(s)
- John A. Crump
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - Robert S. Heyderman
- Division of Infection and Immunity, Faculty of Medical Sciences, University College London, United Kingdom
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, University of Malawi College of Medicine, Blantyre
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Development of a TaqMan Array Card for Acute-Febrile-Illness Outbreak Investigation and Surveillance of Emerging Pathogens, Including Ebola Virus. J Clin Microbiol 2015; 54:49-58. [PMID: 26491176 DOI: 10.1128/jcm.02257-15] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 09/28/2015] [Indexed: 12/20/2022] Open
Abstract
Acute febrile illness (AFI) is associated with substantial morbidity and mortality worldwide, yet an etiologic agent is often not identified. Convalescent-phase serology is impractical, blood culture is slow, and many pathogens are fastidious or impossible to cultivate. We developed a real-time PCR-based TaqMan array card (TAC) that can test six to eight samples within 2.5 h from sample to results and can simultaneously detect 26 AFI-associated organisms, including 15 viruses (chikungunya, Crimean-Congo hemorrhagic fever [CCHF] virus, dengue, Ebola virus, Bundibugyo virus, Sudan virus, hantaviruses [Hantaan and Seoul], hepatitis E, Marburg, Nipah virus, o'nyong-nyong virus, Rift Valley fever virus, West Nile virus, and yellow fever virus), 8 bacteria (Bartonella spp., Brucella spp., Coxiella burnetii, Leptospira spp., Rickettsia spp., Salmonella enterica and Salmonella enterica serovar Typhi, and Yersinia pestis), and 3 protozoa (Leishmania spp., Plasmodium spp., and Trypanosoma brucei). Two extrinsic controls (phocine herpesvirus 1 and bacteriophage MS2) were included to ensure extraction and amplification efficiency. Analytical validation was performed on spiked specimens for linearity, intra-assay precision, interassay precision, limit of detection, and specificity. The performance of the card on clinical specimens was evaluated with 1,050 blood samples by comparison to the individual real-time PCR assays, and the TAC exhibited an overall 88% (278/315; 95% confidence interval [CI], 84% to 92%) sensitivity and a 99% (5,261/5,326, 98% to 99%) specificity. This TaqMan array card can be used in field settings as a rapid screen for outbreak investigation or for the surveillance of pathogens, including Ebola virus.
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43
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Crump JA, Sjölund-Karlsson M, Gordon MA, Parry CM. Epidemiology, Clinical Presentation, Laboratory Diagnosis, Antimicrobial Resistance, and Antimicrobial Management of Invasive Salmonella Infections. Clin Microbiol Rev 2015; 28:901-37. [PMID: 26180063 PMCID: PMC4503790 DOI: 10.1128/cmr.00002-15] [Citation(s) in RCA: 640] [Impact Index Per Article: 71.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Salmonella enterica infections are common causes of bloodstream infection in low-resource areas, where they may be difficult to distinguish from other febrile illnesses and may be associated with a high case fatality ratio. Microbiologic culture of blood or bone marrow remains the mainstay of laboratory diagnosis. Antimicrobial resistance has emerged in Salmonella enterica, initially to the traditional first-line drugs chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole. Decreased fluoroquinolone susceptibility and then fluoroquinolone resistance have developed in association with chromosomal mutations in the quinolone resistance-determining region of genes encoding DNA gyrase and topoisomerase IV and also by plasmid-mediated resistance mechanisms. Resistance to extended-spectrum cephalosporins has occurred more often in nontyphoidal than in typhoidal Salmonella strains. Azithromycin is effective for the management of uncomplicated typhoid fever and may serve as an alternative oral drug in areas where fluoroquinolone resistance is common. In 2013, CLSI lowered the ciprofloxacin susceptibility breakpoints to account for accumulating clinical, microbiologic, and pharmacokinetic-pharmacodynamic data suggesting that revision was needed for contemporary invasive Salmonella infections. Newly established CLSI guidelines for azithromycin and Salmonella enterica serovar Typhi were published in CLSI document M100 in 2015.
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Affiliation(s)
- John A Crump
- Centre for International Health, University of Otago, Dunedin, Otago, New Zealand Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Maria Sjölund-Karlsson
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Melita A Gordon
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Christopher M Parry
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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Liaquat S, Sarwar Y, Ali A, Haque A. Comparative growth analysis of capsulated (Vi+) and acapsulated (Vi-) Salmonella typhi isolates in human blood. EXCLI JOURNAL 2015; 14:213-9. [PMID: 26417360 PMCID: PMC4553862 DOI: 10.17179/excli2014-674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 11/27/2014] [Indexed: 11/10/2022]
Abstract
Salmonella enterica serovar Typhi (S. Typhi) is a human restricted pathogen. It biosynthesizes a virulence capsular polysaccharide named as Vi antigen. S. Typhi regulates expression of genes involved in the biosynthesis of Vi antigen in response to osmolarity. Beside Vi-positive isolates, Vi-negative (acapsulated) isolates are also pathogenic. However, Vi-positive isolates are more prevalent. The present study was planned to investigate comparative growth of Vi-positive and Vi-negative S. Typhi isolates in an ex vivo human whole blood model. Four isolates of each type were tested for growth in human whole blood and in an enrichment medium (Tryptic soy broth-TSB) as a control. It was found that capsulated (Vi-positive) strains formed smooth circular colonies and grew with shorter lag and generation time than Vi-negative isolates. Overall growth pattern of S. Typhi isolates both in vitro and ex vivo conditions showed that Vi-positive isolates grew at a faster rate. Especially in human blood, the lag time of acapsulated isolates was almost doubled as compared to capsulated S. Typhi isolates. It was also observed that Vi-negative isolates reduced in number up to 81 % during the first 12 hours of incubation in human whole blood. Interestingly, both types of isolates had similar growth curve in TSB indicating that Vi capsule is dispensable for bacterial growth in vitro. This study shows for the first time that absence of capsular antigen retards the growth of Vi-negative isolates on initial contact with human blood, but with passage of time they adjust themselves according to the new environment.
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Affiliation(s)
- Sadia Liaquat
- Enteric Pathogen Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan affiliated with Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan ; Department of Bioinformatics and Biotechnology, GC University, Faisalabad, Pakistan
| | - Yasra Sarwar
- Enteric Pathogen Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan affiliated with Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan
| | - Aamir Ali
- Enteric Pathogen Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Pakistan affiliated with Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan
| | - Abdul Haque
- Dean, Faculty of Health Sciences, University of Faisalabad, Pakistan
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Cappella A, Bertoglio B, Castoldi E, Maderna E, Di Giancamillo A, Domeneghini C, Andreola S, Cattaneo C. The taphonomy of blood components in decomposing bone and its relevance to physical anthropology. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2015; 158:636-45. [DOI: 10.1002/ajpa.22830] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/17/2015] [Accepted: 07/23/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Annalisa Cappella
- Dipartimento Di Scienze Biomediche per La Salute, LABANOF, Laboratorio Di Antropologia E Odontologia Forense, Sezione Di Medicina Legale; Università Degli Studi Di Milano; Milan 20133 Italy
| | - Barbara Bertoglio
- Dipartimento Di Scienze Biomediche per La Salute, LABANOF, Laboratorio Di Antropologia E Odontologia Forense, Sezione Di Medicina Legale; Università Degli Studi Di Milano; Milan 20133 Italy
- Fellow of the Genetics; Molecular and Cellular Biology Ph.D. program of the University of Pavia
| | - Elisa Castoldi
- Dipartimento Di Scienze Biomediche per La Salute, LABANOF, Laboratorio Di Antropologia E Odontologia Forense, Sezione Di Medicina Legale; Università Degli Studi Di Milano; Milan 20133 Italy
| | - Emanuela Maderna
- Dipartimento Di Scienze Biomediche per La Salute, LABANOF, Laboratorio Di Antropologia E Odontologia Forense, Sezione Di Medicina Legale; Università Degli Studi Di Milano; Milan 20133 Italy
| | - Alessia Di Giancamillo
- Department of Health, Animal Science and Food Safety; Università Degli Studi Di Milano; Milan 20133 Italy
| | - Cinzia Domeneghini
- Department of Health, Animal Science and Food Safety; Università Degli Studi Di Milano; Milan 20133 Italy
| | - Salvatore Andreola
- Dipartimento Di Scienze Biomediche per La Salute, LABANOF, Laboratorio Di Antropologia E Odontologia Forense, Sezione Di Medicina Legale; Università Degli Studi Di Milano; Milan 20133 Italy
| | - Cristina Cattaneo
- Dipartimento Di Scienze Biomediche per La Salute, LABANOF, Laboratorio Di Antropologia E Odontologia Forense, Sezione Di Medicina Legale; Università Degli Studi Di Milano; Milan 20133 Italy
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46
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Abstract
Salmonella are gram-negative bacilli within the family Enterobacteriaceae. They are the cause of significant morbidity and mortality worldwide. Animals (pets) are an important reservoir for nontyphoidal Salmonella, whereas humans are the only natural host and reservoir for Salmonella Typhi. Salmonella infections are a major cause of gastroenteritis worldwide. They account for an estimated 2.8 billion cases of diarrheal disease each year. The transmission of Salmonella is frequently associated with the consumption of contaminated water and food of animal origin, and it is facilitated by conditions of poor hygiene. Nontyphoidal Salmonella infections have a worldwide distribution, whereas most typhoidal Salmonella infections in the United States are acquired abroad. In the United States, Salmonella is a common agent for food-borne–associated infections. Several outbreaks have been identified and are most commonly associated with agricultural products. Nontyphoidal Salmonella infection is usually characterized by a self-limited gastroenteritis in immunocompetent hosts in industrialized countries, but it may also cause invasive disease in vulnerable individuals (eg, children less than 1 year of age, immunocompromised). Antibiotic treatment is not recommended for treatment of mild to moderate gastroenteritis by nontyphoidal Salmonella in immunocompetent adults or children more than 1 year of age. Antibiotic treatment is recommended for nontyphoidal Salmonella infections in infants less than 3 months of age, because they are at higher risk for bacteremia and extraintestinal complications. Typhoid (enteric) fever and its potential complications have a significant impact on children, especially those who live in developing countries. Antibiotic treatment of typhoid fever has become challenging because of the emergence of Salmonella Typhi strains that are resistant to classically used first-line agents: ampicillin, trimethoprim-sulfamethoxazole, and chloramphenicol. The choice of antibiotics for the management of typhoid fever should be guided by the local resistance pattern. Recommendations include using an extended spectrum cephalosporin, azithromycin, or a fluoroquinolone. Fecal carriage of Salmonella is an important factor in the spread of the organism to healthy individuals. The most important measures to prevent the spread and outbreaks of Salmonella infections and typhoid fever are adequate sanitation protocols for food processing and handling as well as hand hygiene. In the United States, 2 vaccines are commercially available against Salmonella Typhi. The WHO recommends the use of these vaccines in endemic areas and for outbreak control.
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47
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Maude RR, de Jong HK, Wijedoru L, Fukushima M, Ghose A, Samad R, Hossain MA, Karim MR, Faiz MA, Parry CM. The diagnostic accuracy of three rapid diagnostic tests for typhoid fever at Chittagong Medical College Hospital, Chittagong, Bangladesh. Trop Med Int Health 2015; 20:1376-84. [PMID: 26094960 PMCID: PMC4832346 DOI: 10.1111/tmi.12559] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Objective To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh. Methods Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert® blood cultures and real‐time PCR to detect Salmonella enterica Typhi and Paratyphi A and assays for Rickettsia, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test‐it™ Typhoid IgM lateral flow assay detecting IgM antibodies against S. Typhi O antigen, CTKBiotech Onsite Typhoid IgG/IgM Combo Rapid‐test cassette lateral flow assay detecting IgG and IgM antibodies against S. Typhi O and H antigens and SD Bioline line assay for IgG and IgM antibodies against S. Typhi proteins. Results In 300 malaria smear‐negative febrile patients [median (IQR) age of 13.5 (5–31) years], 34 (11.3%) had confirmed typhoid fever: 19 positive by blood culture for S. Typhi (three blood PCR positive) and 15 blood culture negative but PCR positive for S. Typhi in blood. The respective sensitivity and specificity of the three RDTs in patients using a composite reference standard of blood culture and/or PCR‐confirmed typhoid fever were 59% and 61% for LifeAssay, 59% and 74% for the CTK IgM and/or IgG, and 24% and 96% for the SD Bioline RDT IgM and/or IgG. The LifeAssay RDT had a sensitivity of 63% and a specificity of 91% when modified with a positive cut‐off of ≥2+ and analysed using a Bayesian latent class model. Conclusions These typhoid RDTs demonstrated moderate diagnostic accuracies, and better tests are needed.
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Affiliation(s)
- Rapeephan R Maude
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Hanna K de Jong
- Department of Internal Medicine, Division of Infectious Diseases and Center for Infection and Immunity Amsterdam (CINIMA), Amsterdam, The Netherlands.,Center for Experimental Molecular Medicine (CEMM), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Lalith Wijedoru
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Masako Fukushima
- Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - Rasheda Samad
- Chittagong Medical College Hospital, Chittagong, Bangladesh
| | | | | | - Mohammed Abul Faiz
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Specialized Care and Research, Chittagong, Bangladesh
| | - Christopher M Parry
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK.,London School of Hygiene and Tropical Medicine, London, UK.,School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
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48
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Andrews JR, Ryan ET. Diagnostics for invasive Salmonella infections: Current challenges and future directions. Vaccine 2015; 33 Suppl 3:C8-15. [PMID: 25937611 DOI: 10.1016/j.vaccine.2015.02.030] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/03/2015] [Accepted: 02/08/2015] [Indexed: 10/23/2022]
Abstract
Invasive Salmonellosis caused by Salmonella enterica serotype Typhi or Paratyphi A, B, C, or invasive non-typhoidal Salmonella serotypes, is an immensely important disease cluster for which reliable, rapid diagnostic tests are not available. Blood culture remains the gold standard but is insensitive, slow, and resource-intensive. Existing molecular diagnostics have poor sensitivity due to the low organism burden in bodily fluids. Commercially available serologic tests for typhoidal Salmonella have had limited sensitivity and specificity. In high burden, resource-limited settings, reliance on clinical diagnosis or inaccurate tests often results in frequent, unnecessary treatment, which contributes selective pressure for the emergence of antimicrobial resistance. This practice also results in inadequate therapy for other etiologies of acute febrile illnesses, including leptospirosis and rickettsial infections. A number of novel serologic, molecular, transcriptomic and metabolomic approaches to diagnostics are under development. Target product profiles that outline specific needs may focus development and investment, and establish benchmarks for accuracy, cost, speed, and portability of new diagnostics. Of note, a critical barrier to diagnostic assay rollout will be the low cost and low perceived harm of empiric therapy on behalf of providers and patients, which leaves few perceived incentives to utilize diagnostics. Approaches that align incentives with societal goals of limiting inappropriate antimicrobial use, such as subsidizing diagnostics, may be essential for stimulating development and uptake of such assays in resource-limited settings. New diagnostics for invasive Salmonellosis should be developed and deployed alongside diagnostics for alternative etiologies of acute febrile illnesses to improve targeted use of antibiotics.
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Affiliation(s)
- Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, United States.
| | - Edward T Ryan
- Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States.
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Abstract
In this issue of Blood, Malleret and colleagues show the importance of the bone marrow in Plasmodium vivax biology by proving the preferential infection of young reticulocytes (generally restricted to the bone marrow), which then experience accelerated maturation postinvasion.
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50
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Bone marrow granuloma in typhoid Fever: a morphological approach and literature review. Case Rep Infect Dis 2015; 2015:628028. [PMID: 25789187 PMCID: PMC4350621 DOI: 10.1155/2015/628028] [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: 10/30/2014] [Accepted: 02/10/2015] [Indexed: 11/30/2022] Open
Abstract
Typhoid fever is one of the few bacterial infections in humans where bone marrow evaluation is routinely recommended. However, the morphological aspect of typhoid fever in bone marrow has been rarely described in the literature. We describe a 25-year-old male patient who presented with prolonged fever suspected to be of tubercular etiology. Bone marrow examination showed well-formed histiocytic and epithelioid granulomas and erythrophagocytosis; and the bone marrow aspirate culture grew Salmonella typhi A. In view of potential clinical implications, typhoid fever should be considered as a differential diagnosis to tuberculosis in the evaluation of prolonged fever; especially in high prevalent areas. We suggest that erythrophagocytosis may serve as a morphological marker in typhoid granulomas in the bone marrow; and bone marrow culture should be submitted in every suspected case for appropriate patient management.
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