1
|
Greig DR, Bird MT, Chattaway MA, Langridge GC, Waters EV, Ribeca P, Jenkins C, Nair S. Characterization of a P1-bacteriophage-like plasmid (phage-plasmid) harbouring bla CTX-M-15 in Salmonella enterica serovar Typhi. Microb Genom 2022; 8:mgen000913. [PMID: 36748517 PMCID: PMC9837566 DOI: 10.1099/mgen.0.000913] [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] [Indexed: 12/12/2022] Open
Abstract
Antimicrobial-resistance (AMR) genes can be transferred between microbial cells via horizontal gene transfer (HGT), which involves mobile and integrative elements such as plasmids, bacteriophages, transposons, integrons and pathogenicity islands. Bacteriophages are found in abundance in the microbial world, but their role in virulence and AMR has not fully been elucidated in the Enterobacterales. With short-read sequencing paving the way to systematic high-throughput AMR gene detection, long-read sequencing technologies now enable us to establish how such genes are structurally connected into meaningful genomic units, raising questions about how they might cooperate to achieve their biological function. Here, we describe a novel ~98 kbp circular P1-bacteriophage-like plasmid termed ph681355 isolated from a clinical Salmonella enterica serovar Typhi isolate. It carries bla CTX-M-15, an IncY plasmid replicon (repY gene) and the ISEcP1 mobile element and is, to our knowledge, the first reported P1-bacteriophage-like plasmid (phage-plasmid) in S. enterica Typhi. We compared ph681355 to two previously described phage-plasmids, pSJ46 from S. enterica serovar Indiana and pMCR-1-P3 from Escherichia coli, and found high nucleotide similarity across the backbone. However, we saw low ph681355 backbone similarity to plasmid p60006 associated with the extensively drug-resistant S. enterica Typhi outbreak isolate in Pakistan, providing evidence of an alternative route for bla CTX-M-15 transmission. Our discovery highlights the importance of utilizing long-read sequencing in interrogating bacterial genomic architecture to fully understand AMR mechanisms and their clinical relevance. It also raises questions regarding how widespread bacteriophage-mediated HGT might be, suggesting that the resulting genomic plasticity might be higher than previously thought.
Collapse
Affiliation(s)
- David R. Greig
- National Infection Service, UK Health Security Agency, London NW9 5EQ, UK,NIHR Health Protection Research Unit in Gastrointestinal Pathogens, Liverpool, UK,Division of Infection and Immunity, Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush EH25 9RG, UK
| | - Matthew T. Bird
- National Infection Service, UK Health Security Agency, London NW9 5EQ, UK,NIHR Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Oxford, UK
| | | | | | - Emma V. Waters
- Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Paolo Ribeca
- National Infection Service, UK Health Security Agency, London NW9 5EQ, UK,NIHR Health Protection Research Unit in Genomics and Enabling Data, Warwick, UK
| | - Claire Jenkins
- National Infection Service, UK Health Security Agency, London NW9 5EQ, UK,NIHR Health Protection Research Unit in Gastrointestinal Pathogens, Liverpool, UK
| | - Satheesh Nair
- National Infection Service, UK Health Security Agency, London NW9 5EQ, UK,*Correspondence: Satheesh Nair,
| |
Collapse
|
2
|
Abstract
PURPOSE OF REVIEW Momentum for achieving widespread control of typhoid fever has been growing over the past decade. Typhoid conjugate vaccines represent a potentially effective tool to reduce the burden of disease in the foreseeable future and new data have recently emerged to better frame their use-case. RECENT FINDINGS We describe how antibiotic resistance continues to pose a major challenge in the treatment of typhoid fever, as exemplified by the emergence of azithromycin resistance and the spread of Salmonella Typhi strains resistant to third-generation cephalosporins. We review efficacy and effectiveness data for TCVs, which have been shown to have high-level efficacy (≥80%) against typhoid fever in diverse field settings. Data from randomized controlled trials and observational studies of TCVs are reviewed herein. Finally, we review data from multicountry blood culture surveillance studies that have provided granular insights into typhoid fever epidemiology. These data are becoming increasingly important as countries decide how best to introduce TCVs into routine immunization schedules and determine the optimal delivery strategy. SUMMARY Continued advocacy is needed to address the ongoing challenge of typhoid fever to improve child health and tackle the rising challenge of antimicrobial resistance.
Collapse
|
3
|
McCann N, Nabarro L, Morris-Jones S, Patel T, Godbole G, Heyderman R, Brown M. Outpatient management of uncomplicated enteric fever: A case series of 93 patients from the Hospital of Tropical Diseases, London. J Infect 2022; 85:397-404. [PMID: 35781016 DOI: 10.1016/j.jinf.2022.06.025] [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: 03/04/2022] [Revised: 05/04/2022] [Accepted: 06/24/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Enteric fever is predominantly managed as an outpatient condition in endemic settings but there is little evidence to support this approach in non-endemic settings. This study aims to review the outcomes of outpatients treated for enteric fever at the Hospital of Tropical Diseases in London, UK. METHODS We conducted a retrospective analysis of all patients with confirmed enteric fever between August 2009 and September 2020. Demographic, clinical, laboratory and microbiological data were collected and compared between the inpatient and outpatient populations. Outcomes investigated were complicated enteric fever, treatment failure and relapse. RESULTS Overall, 93 patients (59% male, median age 31) were identified with blood and/or stool culture confirmed enteric fever and 49 (53%) of these were managed as outpatients. The commonest empirical treatment for outpatients was azithromycin (70%) and for inpatients was ceftriaxone (84%). Outpatients were more likely than inpatients to receive only one antibiotic (57% vs 19%, p < 0.01) and receive a shorter duration of antibiotics (median 7 vs 11 days, p <0.01). There were no cases of complicated disease or relapse in either the inpatient or outpatient groups. There was one treatment failure in the outpatient group. Azithromycin was well-tolerated with no reported side effects. CONCLUSIONS Our findings suggest that outpatient management of uncomplicated imported enteric fever is safe and effective with the use of oral azithromycin. Careful monitoring of patients is recommended as treatment failure can occur.
Collapse
Affiliation(s)
- N McCann
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK.
| | - L Nabarro
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; St George's University Hospitals NHS Foundation Trust, London, UK
| | - S Morris-Jones
- 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
| | - T Patel
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK
| | - G Godbole
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Gastrointestinal Pathogens and Food Safety (One Health), United Kingdom Health Security Agency, UK
| | - R 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
| |
Collapse
|
4
|
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.
Collapse
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.
| |
Collapse
|
5
|
Bhutta ZA. International Travel and the Risk of Extensively Drug-resistant Typhoid: Issues and Potential Solutions. Clin Infect Dis 2021; 73:e4590-e4591. [PMID: 32609356 DOI: 10.1093/cid/ciaa908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 06/26/2020] [Indexed: 11/13/2022] Open
Affiliation(s)
- Zulfiqar A Bhutta
- Centre for Global Child Health, Hospital for Sick Children, Toronto, Canada
| |
Collapse
|
6
|
Performance of Immunodiagnostic Tests for Typhoid Fever: A Systematic Review and Meta-Analysis. Pathogens 2021; 10:pathogens10091184. [PMID: 34578216 PMCID: PMC8467574 DOI: 10.3390/pathogens10091184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/01/2021] [Accepted: 09/07/2021] [Indexed: 12/23/2022] Open
Abstract
Typhoid fever, also known as typhoid, is a life-threatening bacterial infection that remains a global health concern. The infection is associated with a significant morbidity and mortality rate, resulting in an urgent need for specific and rapid detection tests to aid prevention and management of the disease. The present review aims to assess the specificity and sensitivity of the available literature on the immunodiagnostics of typhoid fever. A literature search was conducted using three databases (PubMed, ProQuest and Scopus) and manual searches through the references of identified full texts to retrieve relevant literature published between 1 January 2011 and 31 December 2020. Of the 577 studies identified in our search, 12 were included in further analysis. Lipopolysaccharides (LPS) and hemolysin E (HlyE) were the most frequently studied antigens. The specimens examined in these studies included serum and saliva. Using blood culture as the gold standard, anti-LPS IgA gave the highest sensitivity of 96% (95% CI: 93–99) and specificity of 96% (95% CI: 93–99) for distinguishing between typhoid cases and healthy controls, whereas the combination of anti-LPS and anti-flagellin total IgGAM gave the highest sensitivity of 93% (95% CI: 86–99) and specificity of 95% (95% CI: 89–100) for distinguishing typhoid cases and other febrile infections. A comparably high sensitivity of 92% (95% CI: 86–98) and specificity of 89% (95% CI: 78–100) were shown in testing based on detection of the combination of anti-LPS (IgA and IgM) and anti-HlyE IgG as well as a slightly lower sensitivity of 91% (95% CI: 74–100) in the case of anti-50kDa IgA. Anti-50kDa IgM had the lowest sensitivity of 36% (95% CI: 6–65) against both healthy and febrile controls. The development of a rapid diagnostic test targeting antibodies against lipopolysaccharides combined with flagellin appeared to be a suitable approach for the rapid detection test of typhoid fever. Saliva is added benefit for rapid typhoid diagnosis since it is less invasive. As a result, further studies could be done to develop additional approaches for adopting such samples.
Collapse
|
7
|
Herdman MT, Karo B, Dave J, Katwa P, Freedman J, Do Nascimento V, Kirkbride H, Chattaway MA, Godbole G, Balasegaram S. Increasingly limited options for the treatment of enteric fever in travellers returning to England, 2014-2019: a cross-sectional analytical study. J Med Microbiol 2021; 70. [PMID: 34351258 PMCID: PMC8513630 DOI: 10.1099/jmm.0.001359] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Introduction. Enteric fever (caused by Salmonella enterica serovars Typhi and Paratyphi) frequently presents as an acute, undifferentiated febrile illness in returning travellers, requiring timely empirical antibiotics.Gap Statement. Determining which empirical antibiotics to prescribe for enteric fever requires up-to-date knowledge of susceptibility patterns.Aim. By characterising factors associated with antimicrobial resistance in cases of S. Typhi and S. Paratyphi imported to England, we aim to guide effective empirical treatment.Methodology. All English isolates of S. Typhi and S. Paratyphi 2014-2019 underwent antimicrobial susceptibility testing; results were compared to a previous survey in London 2005-2012. Risk factors for antimicrobial resistance were analysed with logistic regression models to predict adjusted odds ratios (aOR) for resistance to individual antibiotics and multi-drug resistance.Results. We identified 1088 cases of S. Typhi, 729 S. Paratyphi A, 93 S. Paratyphi B, and one S. Paratyphi C. In total, 93 % were imported. Overall, 90 % of S. Typhi and 97 % of S. Paratyphi A isolates were resistant to ciprofloxacin; 26 % of S. Typhi were multidrug resistant to ciprofloxacin, amoxicillin, co-trimoxazole, and chloramphenicol (MDR+FQ). Of the isolates, 4 % of S. Typhi showed an extended drug resistance (XDR) phenotype of MDR+FQ plus resistance to third-generation cephalosporins, with cases of XDR rising sharply in recent years (none before 2017, one in 2017, six in 2018, 32 in 2019). For S. Typhi isolates, resistance to ciprofloxacin was associated with travel to Pakistan (aOR=32.0, 95 % CI: 15.4-66.4), India (aOR=21.8, 95 % CI: 11.6-41.2), and Bangladesh (aOR=6.2, 95 % CI: 2.8-13.6) compared to travel elsewhere, after adjusting for rising prevalence of resistance over time. MDR+FQ resistance in S. Typhi isolates was associated with travel to Pakistan (aOR=3.5, 95 % CI: 2.4-5.2) and less likely with travel to India (aOR=0.07, 95 % CI 0.04-0.15) compared to travel elsewhere. All XDR cases were imported from Pakistan. No isolate was resistant to azithromycin. Comparison with the 2005-2012 London survey indicates substantial increases in the prevalence of resistance of S. Typhi isolates to ciprofloxacin associated with travel to Pakistan (from 79-98 %) and Africa (from 12-60 %).Conclusion. Third-generation cephalosporins and azithromycin remain appropriate choices for empirical treatment of enteric fever in most returning travellers to the UK from endemic countries, except from Pakistan, where XDR represents a significant risk.
Collapse
Affiliation(s)
- M Trent Herdman
- National Infection Service, Public Health England, England, UK
| | - Basel Karo
- National Infection Service, Public Health England, England, UK
| | - Jayshree Dave
- National Infection Service, Public Health England, England, UK
| | - Parisha Katwa
- National Infection Service, Public Health England, England, UK
| | - Joanne Freedman
- National Infection Service, Public Health England, England, UK.,Health Education, East of England, Cambridge, UK
| | | | | | | | - Gauri Godbole
- National Infection Service, Public Health England, England, UK
| | | |
Collapse
|
8
|
Nair S, Chattaway M, Langridge GC, Gentle A, Day M, Ainsworth EV, Mohamed I, Smith R, Jenkins C, Dallman TJ, Godbole G. ESBL-producing strains isolated from imported cases of enteric fever in England and Wales reveal multiple chromosomal integrations of blaCTX-M-15 in XDR Salmonella Typhi. J Antimicrob Chemother 2021; 76:1459-1466. [DOI: 10.1093/jac/dkab049] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/28/2021] [Indexed: 01/18/2023] Open
Abstract
Abstract
Background
There are approximately 300 cases of enteric fever reported annually from England and Wales; most are imported infections. Clinical management of enteric fever remains a challenge with the emergence of ESBL-producing strains, especially XDR Salmonella Typhi from Sindh, Pakistan.
Methods
All strains of S. Typhi and Salmonella Paratyphi A isolated from cases presenting with symptoms of enteric fever in England and Wales, between 1 April 2014 and 31 March 2020, were characterized using WGS. Antibiotic susceptibility testing was performed using an agar dilution method.
Results
ESBL strains contributed to 69 cases of enteric fever (S. Typhi n = 68, S. Paratyphi A n = 1); 68 were imported (Pakistan n = 64, Iraq n = 2, Bangladesh n = 1 and India n = 1). Ages ranged from 1 to 56 years, 36/69 (52%) were children, 52% were female and the duration of hospital stay ranged from 1 to 23 days. The ESBL phenotype was conferred by the presence of blaCTX-M-15 (S. Typhi n = 67 and S. Paratyphi A n = 1) or blaCTX-M-55 (S. Typhi n = 1). An IncY plasmid harbouring blaCTX-M-15 and qnr was detected in 56 strains from Pakistan. The IncY plasmid was absent in the remaining strains and there was evidence of a 4 kb ISEcpl-blaCTX-M-15-tnp gene cassette insertion into the chromosome at one of three integration points.
Conclusions
Chromosomal integration of blaCTX-M-15 within the XDR Sindh strains may lead to the maintenance of resistance in the absence of antibiotic selection pressure. Empirical treatment of cases of complicated enteric fever returning from Pakistan will henceforth have to include a carbapenem.
Collapse
Affiliation(s)
- Satheesh Nair
- Gastrointestinal Bacteria Reference Unit, National Infection Service, Public Health England, London, UK
| | - Marie Chattaway
- Gastrointestinal Bacteria Reference Unit, National Infection Service, Public Health England, London, UK
| | | | - Amy Gentle
- Gastrointestinal Bacteria Reference Unit, National Infection Service, Public Health England, London, UK
| | - Martin Day
- Gastrointestinal Bacteria Reference Unit, National Infection Service, Public Health England, London, UK
| | - Emma V Ainsworth
- Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Iman Mohamed
- Travel Health and International Health Regulations, National Infection Service, Public Health England, London, UK
| | - Robert Smith
- Communicable Disease Surveillance Centre, Public Health Wales, Cardiff, UK
| | - Claire Jenkins
- Gastrointestinal Pathogens Department, National Infection Service, Public Health England, London, UK
| | - Timothy J Dallman
- Gastrointestinal Bacteria Reference Unit, National Infection Service, Public Health England, London, UK
| | - Gauri Godbole
- Gastrointestinal Pathogens Department, National Infection Service, Public Health England, London, UK
| |
Collapse
|
9
|
Goldblatt J, Ward A, Yusuf M, Day M, Godbole G, Morris-Jones S. Azithromycin susceptibility testing for Salmonella enterica isolates: discordances in results using MIC gradient strips. J Antimicrob Chemother 2020; 75:1820-1823. [PMID: 32221592 DOI: 10.1093/jac/dkaa097] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 02/14/2020] [Accepted: 02/19/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Azithromycin resistance is emerging in typhoidal Salmonella. Confirmation of azithromycin MIC is the most frequent antibiotic susceptibility request made to the Gastrointestinal Bacteria Reference Unit (GBRU) laboratory in England by local diagnostic laboratories. OBJECTIVES (i) Determine concordance between local diagnostic and reference laboratory estimations of azithromycin MIC by gradient strip in Salmonella enterica serovars Typhi and Paratyphi. (ii) Consider causes of variation. METHODS Isolates from patients with enteric fever attending a central London hospital between May 2011 and April 2019 were tested for azithromycin susceptibility using gradient strips, according to EUCAST methodology. Matched local diagnostic and reference laboratory estimations of azithromycin and ciprofloxacin (as a comparator) MICs were included; concordance in estimations was examined. RESULTS Local diagnostic laboratory readings overestimated azithromycin MIC values compared with the reference laboratory, resulting in poor concordance in susceptibility/resistance attribution (concordant susceptibility interpretation in 8/19, κ = 0). In contrast, ciprofloxacin MIC estimation demonstrated superior concordance (concordant susceptibility interpretation in 16/17, κ = 0.85). None of the isolates was resistant to azithromycin at the reference laboratory and no known genes associated with azithromycin resistance were detected in any isolate using WGS. CONCLUSIONS Overestimation of azithromycin resistance is likely to be due to difficulty in interpreting the point of intersection of the 'trailing edge' with the gradient strip, used to determine MIC. We advise local diagnostic laboratories to review their experience and consider adopting a 'second reader' system to mitigate this.
Collapse
Affiliation(s)
- Jennifer Goldblatt
- Department of Clinical Microbiology, University College London Hospital NHS Foundation Trust, 5th Floor, 250 Euston Road, London NW1 2PG, UK
| | - Andrew Ward
- The Doctors Laboratory, The Halo Building, 1 Mabledon Place, London WC1H 9AX, UK
| | - Mohammed Yusuf
- Health Services Laboratories, 1 Mabledon Place, London WC1H 9AX, UK
| | - Martin Day
- Gastrointestinal Bacteria Reference Unit, Public Health England, National Infection Service, Colindale, London NW9 5EQ, UK
| | - Gauri Godbole
- Gastrointestinal Bacteria Reference Unit, Public Health England, National Infection Service, Colindale, London NW9 5EQ, UK
| | - Stephen Morris-Jones
- Department of Clinical Microbiology, University College London Hospital NHS Foundation Trust, 5th Floor, 250 Euston Road, London NW1 2PG, UK
| |
Collapse
|
10
|
François Watkins LK, Winstead A, Appiah GD, Friedman CR, Medalla F, Hughes MJ, Birhane MG, Schneider ZD, Marcenac P, Hanna SS, Godbole G, Walblay KA., Wiggington AE, Leeper M, Meservey EH, Tagg KA, Chen JC, Abubakar A, Lami F, Asaad AM, Sabaratnam V, Ikram A, Angelo KM, Walker A, Mintz E. Update on Extensively Drug-Resistant Salmonella Serotype Typhi Infections Among Travelers to or from Pakistan and Report of Ceftriaxone-Resistant Salmonella Serotype Typhi Infections Among Travelers to Iraq - United States, 2018-2019. MMWR-MORBIDITY AND MORTALITY WEEKLY REPORT 2020; 69:618-622. [PMID: 32437343 PMCID: PMC7357342 DOI: 10.15585/mmwr.mm6920a2] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
11
|
Jin C, Gibani MM, Pennington SH, Liu X, Ardrey A, Aljayyoussi G, Moore M, Angus B, Parry CM, Biagini GA, Feasey NA, Pollard AJ. Treatment responses to Azithromycin and Ciprofloxacin in uncomplicated Salmonella Typhi infection: A comparison of Clinical and Microbiological Data from a Controlled Human Infection Model. PLoS Negl Trop Dis 2019; 13:e0007955. [PMID: 31877141 PMCID: PMC6948818 DOI: 10.1371/journal.pntd.0007955] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 01/08/2020] [Accepted: 11/26/2019] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The treatment of enteric fever is complicated by the emergence of antimicrobial resistant Salmonella Typhi. Azithromycin is commonly used for first-line treatment of uncomplicated enteric fever, but the response to treatment may be sub-optimal in some patient groups when compared with fluoroquinolones. METHODS We performed an analysis of responses to treatment with azithromycin (500mg once-daily, 14 days) or ciprofloxacin (500mg twice-daily, 14 days) in healthy UK volunteers (18-60 years) enrolled into two Salmonella controlled human infection studies. Study A was a single-centre, open-label, randomised trial. Participants were randomised 1:1 to receive open-label oral ciprofloxacin or azithromycin, stratified by vaccine group (Vi-polysaccharide, Vi-conjugate or control Men-ACWY vaccine). Study B was an observational challenge/re-challenge study, where participants were randomised to challenge with Salmonella Typhi or Salmonella Paratyphi A. Outcome measures included fever clearance time, blood-culture clearance time and a composite measure of prolonged treatment response (persistent fever ≥38.0°C for ≥72 hours, persistently positive S. Typhi blood cultures for ≥72 hours, or change in antibiotic treatment). Both trials are registered with ClinicalTrials.gov (NCT02324751 and NCT02192008). FINDINGS In 81 participants diagnosed with S. Typhi in two studies, treatment with azithromycin was associated with prolonged bacteraemia (median 90.8 hours [95% CI: 65.9-93.8] vs. 20.1 hours [95% CI: 7.8-24.3], p<0.001) and prolonged fever clearance times <37.5°C (hazard ratio 2.4 [95%CI: 1.2-5.0]; p = 0.02). Results were consistent when studies were analysed independently and in a sub-group of participants with no history of vaccination or previous challenge. A prolonged treatment response was observed significantly more frequently in the azithromycin group (28/52 [54.9%]) compared with the ciprofloxacin group (1/29 [3.5%]; p<0.001). In participants treated with azithromycin, observed systemic plasma concentrations of azithromycin did not exceed the minimum inhibitory concentration (MIC), whilst predicted intracellular concentrations did exceed the MIC. In participants treated with ciprofloxacin, the observed systemic plasma concentrations and predicted intracellular concentrations of ciprofloxacin exceeded the MIC. INTERPRETATION Azithromycin at a dose of 500mg daily is an effective treatment for fully sensitive strains of S. Typhi but is associated with delayed treatment response and prolonged bacteraemia when compared with ciprofloxacin within the context of a human challenge model. Whilst the cellular accumulation of azithromycin is predicted to be sufficient to treat intracellular S. Typhi, systemic exposure may be sub-optimal for the elimination of extracellular circulating S. Typhi. In an era of increasing antimicrobial resistance, further studies are required to define appropriate azithromycin dosing regimens for enteric fever and to assess novel treatment strategies, including combination therapies. TRIAL REGISTRATION ClinicalTrials.gov (NCT02324751 and NCT02192008).
Collapse
Affiliation(s)
- Celina Jin
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Malick M. Gibani
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
- Department of Infectious Diseases, Imperial College London, London, United Kingdom
| | - Shaun H. Pennington
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Xinxue Liu
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Alison Ardrey
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Ghaith Aljayyoussi
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Maria Moore
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| | - Brian Angus
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Christopher M. Parry
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- School of Tropical Medicine and Global Health, Nagsaki University, Nagasaki, Japan
| | - Giancarlo A. Biagini
- Research Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Nicholas A. Feasey
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- Malawi Liverpool Wellcome Trust Clinical research Programme, Blantyre, Malawi
| | - Andrew J. Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom
| |
Collapse
|