Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Dissemination of Multiresistant Bacteria: Their Selection, Transmission, Virulence and Resistance
Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Klinisk mikrobiologi.
2019 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

Multiresistant bacteria are an emerging threat in modern medicine. Consumption of antimicrobial agents among humans, animals and in agriculture causes a selection of resistance genes. Dissemination of bacteria carrying resistance genes occurs both globally and locally, and hospital settings pose a special risk for spread when staff, environment and vulnerable patients interact. The overall aim of this thesis was to analyse underlying factors that facilitate the dissemination of multiresistant pathogenic bacteria in hospital settings.

Clusters of resistant bacteria from six occasions were investigated. Vancomycin-Resistant Enterococci (VRE), Methicillin-Resistant Staphylococcus pseudintermedius (MSRP), ESBL-producing Escherichia coli and Klebsiella pneumoniae, and carbapenemase-producing Pseudomonas aeruginosa were analysed by a range of methods, from cultures on broth to PCR and whole genome sequencing. Type of resistance, clonality, virulence factors, mobile genetic elements, epidemiology, survival in the environment, and patient history were examined variously depending on study.

The results showed that VRE resistance genes can be acquired during treatment with vancomycin. Furthermore, contamination of the hospital environment could quickly cause an outbreak, when patients are frequently relocated and exposition to contaminated rooms increase. Resistant bacteria emerging among companion animals, such as the dog-associated MRSP, can pose a zoonotic threat, when a virulent clone finds a new niche in humans.

The ability of Gram-negative bacteria to survive in a hospital environment is probably better than expected, given the right prerequisites; incorrect use of sinks enabled the spread of ESBL-producing K. pneumoniae and carbapenemase-producing P. aeruginosa. Additionally, the survival on hospital associated materials was longer for ESBL-producing E. coli than the AmpC-producing counterpart, which could tell part of why ESBL-producing E. coli is increasing. Hence, the survival in the environment calls for consideration when choosing materials and equipment for hospitals and nursing homes.

Exchange of bacteria occurs continuously between humans and our surroundings. Outbreaks of multiresistant bacteria are rare in Sweden but expose the weaknesses in healthcare when occurring. The organization, materials and equipment of hospitals facilitate the dissemination of resistant bacteria, as does animals and humans around us and even the genes in our own microbiota.

Ort, förlag, år, upplaga, sidor
Uppsala: Acta Universitatis Upsaliensis, 2019. , s. 84
Serie
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, ISSN 1651-6206 ; 1527
Nationell ämneskategori
Infektionsmedicin
Forskningsämne
Klinisk bakteriologi
Identifikatorer
URN: urn:nbn:se:uu:diva-369302ISBN: 978-91-513-0537-0 (tryckt)OAI: oai:DiVA.org:uu-369302DiVA, id: diva2:1270320
Disputation
2019-02-15, Jupiter, The Hub, Science Park, Dag Hammarskjölds väg 38, Uppsala, 13:00 (Engelska)
Opponent
Handledare
Tillgänglig från: 2019-01-22 Skapad: 2018-12-12 Senast uppdaterad: 2019-02-18
Delarbeten
1. Fatal acquisition of vanD gene during vancomycin treatment of septicaemia caused by Enterococcus faecium
Öppna denna publikation i ny flik eller fönster >>Fatal acquisition of vanD gene during vancomycin treatment of septicaemia caused by Enterococcus faecium
2016 (Engelska)Ingår i: Journal of Hospital Infection, ISSN 0195-6701, E-ISSN 1532-2939, Vol. 92, nr 4, s. 409-410Artikel i tidskrift, Letter (Refereegranskat) Published
Nationell ämneskategori
Infektionsmedicin
Identifikatorer
urn:nbn:se:uu:diva-299109 (URN)10.1016/j.jhin.2016.01.002 (DOI)000373282000019 ()26876745 (PubMedID)
Tillgänglig från: 2016-07-15 Skapad: 2016-07-14 Senast uppdaterad: 2018-12-12Bibliografiskt granskad
2. Cluster of Infections Caused by Methicillin-Resistant Staphylococcus pseudintermedius in Humans in a Tertiary Hospital
Öppna denna publikation i ny flik eller fönster >>Cluster of Infections Caused by Methicillin-Resistant Staphylococcus pseudintermedius in Humans in a Tertiary Hospital
Visa övriga...
2014 (Engelska)Ingår i: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 52, nr 8, s. 3118-3120Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The dog-associated Staphylococcus pseudintermedius is a rare pathogen in humans. Here we describe a cluster of infections caused by the methicillin-resistant S. pseudintermedius clone ST71-J-t02-II-III. It involved four elderly patients at a tertiary hospital. Three patients had wound infections, and the strain had a tendency to cause bullous skin lesions.

Nationell ämneskategori
Mikrobiologi inom det medicinska området
Identifikatorer
urn:nbn:se:uu:diva-231237 (URN)10.1128/JCM.00703-14 (DOI)000339544200062 ()
Tillgänglig från: 2014-09-08 Skapad: 2014-09-05 Senast uppdaterad: 2018-12-12Bibliografiskt granskad
3. The Initial Epidemiology of a Major Clonal Outbreak Caused by VanB-Carrying Enterococcus faecium Clone ST192
Öppna denna publikation i ny flik eller fönster >>The Initial Epidemiology of a Major Clonal Outbreak Caused by VanB-Carrying Enterococcus faecium Clone ST192
(Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
Nationell ämneskategori
Infektionsmedicin
Identifikatorer
urn:nbn:se:uu:diva-369413 (URN)
Tillgänglig från: 2018-12-12 Skapad: 2018-12-12 Senast uppdaterad: 2018-12-12
4. Minor outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in an intensive care unit due to a contaminated sink
Öppna denna publikation i ny flik eller fönster >>Minor outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in an intensive care unit due to a contaminated sink
2012 (Engelska)Ingår i: Journal of Hospital Infection, ISSN 0195-6701, E-ISSN 1532-2939, Vol. 82, nr 2, s. 122-124Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

During a period of seven months four patients on the neurosurgical intensive care unit at a tertiary care hospital in Sweden became infected or colonized by an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strain. The investigation revealed that the source of the outbreak was a contaminated sink. By replacing the sink and its plumbing and improving routines regarding sink practices, the outbreak was successfully controlled.

Nyckelord
Environmental source, Extended-spectrum, beta-lactamase, Klebsiella pneumoniae, Outbreak
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:uu:diva-183561 (URN)10.1016/j.jhin.2012.07.004 (DOI)000309045400007 ()
Tillgänglig från: 2012-12-07 Skapad: 2012-10-29 Senast uppdaterad: 2018-12-12Bibliografiskt granskad
5. The first Swedish outbreak with VIM-2-producing Pseudomonas aeruginosa was prolonged and probably due to contaminated hospital sinks
Öppna denna publikation i ny flik eller fönster >>The first Swedish outbreak with VIM-2-producing Pseudomonas aeruginosa was prolonged and probably due to contaminated hospital sinks
Visa övriga...
(Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
Abstract [en]

Background: Metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa is an increasing clinical problem worldwide. VIM-2 is the predominant enzyme, and it has been linked to several outbreaks. During the spring of 2006, a cluster of patients were colonized or infected with multiresistant Pseudomonas aeruginosa at two neighbouring hospitals in southeast Sweden.

Aim: To describe the first documented outbreak of a VIM-2-producing P. aeruginosa strain in Sweden.

Methods: The isolates were characterized with PCR, pulse-field gel electrophoresis (PFGE), and whole genome sequencing. Patient charts, laboratory records and hygiene routines were reviewed, and patients, staff and the environment were screened.

Findings: The investigation revealed that it was a clonal outbreak of a VIM-2-producing P. aeruginosa strain susceptible only to gentamicin and colistin. It belonged to the high-risk clonal complex 111. No direct contact between patients could be established, but most of them had stayed in the same room/wards with weeks to months apart. Environmental cultures from two sinks yielded growth of P. aeruginosa with the same PFGE-pattern as the patient isolates. The outbreak ended when control measures against the sinks were taken.

Conclusions: Contaminated hospital sinks were the probable reservoir in the first nosocomial outbreak of MBL-producing P. aeruginosa in Sweden. When facing prolonged outbreaks with this bacterium, sinks and other water sources in the hospital environment should be considered. By implementing proactive control measures to limit the bacterial load in sinks and plumbing systems, the waterborne transmission of P. aeruginosa could probably be reduced.

Nationell ämneskategori
Infektionsmedicin
Forskningsämne
Klinisk bakteriologi
Identifikatorer
urn:nbn:se:uu:diva-369296 (URN)
Tillgänglig från: 2018-12-11 Skapad: 2018-12-11 Senast uppdaterad: 2018-12-12
6. Survival in the environment is a possible key factor for the expansion of Escherichia coli strains producing extended-spectrum beta-lactamases
Öppna denna publikation i ny flik eller fönster >>Survival in the environment is a possible key factor for the expansion of Escherichia coli strains producing extended-spectrum beta-lactamases
2014 (Engelska)Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 122, nr 1, s. 59-67Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Acquired resistance to cephalosporins in Enterobacteriaceae is a global problem. After an outbreak at Uppsala University Hospital of extended-spectrum -lactamase (ESBL)-positive Klebsiella pneumoniae producing CTX-M-15, there was a shift from AmpC to ESBL production among Escherichia coli isolates. To explore the basis for this epidemiological shift, 46 E. coli isolates (ESBLs, n=23; AmpC, n=23) were characterized with regard to genetic relatedness, -lactamase, replicon and integron types, antibiotic resistance profiles, and genes encoding virulence factors. In addition, the survival in the environment and on hospital-associated materials was analysed. CTX-M-15 was the most frequent ESBL (78%). Only three (13%) of the AmpC enzymes were harboured on plasmids (CMY-2, DHA-1). Independent of plasmid-mediated beta-lactamase, IncF plasmids predominated and only class I integrons were detected. The ESBL producers carried more virulence genes (p=0.04), exhibited a broader resistance phenotype (p=0.01) and survived significantly longer (p=0.03) on different materials than the AmpC-producing isolates. In conclusion, ESBL-producing isolates had properties which are likely to augment their competitiveness. Apart from antibiotic resistance and virulence factors, extended survival in the environment could be a selective trait for successful ESBL-producing E. coli strains.

Nyckelord
E-coli, AmpC, ESBL, environment, virulence genes, plasmids
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:uu:diva-216726 (URN)10.1111/apm.12102 (DOI)000328909100008 ()
Tillgänglig från: 2014-01-27 Skapad: 2014-01-24 Senast uppdaterad: 2018-12-12Bibliografiskt granskad
7. Lack of hygiene routines among patients and family members at patient hotels - a possible route for transmitting puerperal fever
Öppna denna publikation i ny flik eller fönster >>Lack of hygiene routines among patients and family members at patient hotels - a possible route for transmitting puerperal fever
2010 (Engelska)Ingår i: Scandinavian Journal of Infectious Diseases, ISSN 0036-5548, E-ISSN 1651-1980, Vol. 42, s. 554-556Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The use of patient hotels for ambulatory care of women with uncomplicated deliveries has become a routine in Sweden. This report describes a minor outbreak of a group A Streptococcus strain in 2 newly delivered mothers and their newborn babies at a patient hotel.

Nationell ämneskategori
Infektionsmedicin
Identifikatorer
urn:nbn:se:uu:diva-366358 (URN)10.3109/00365541003699656 (DOI)
Tillgänglig från: 2018-11-20 Skapad: 2018-11-20 Senast uppdaterad: 2018-12-12
8. First documented case of a Staphylococcus lugdunensis strain carrying the mecA gene in Northern Europe
Öppna denna publikation i ny flik eller fönster >>First documented case of a Staphylococcus lugdunensis strain carrying the mecA gene in Northern Europe
2011 (Engelska)Ingår i: Infection Ecology & Epidemiology, ISSN 2000-8686, E-ISSN 2000-8686, Vol. 1, s. 8410-Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Staphylococcus lugdunensis is a clinically common wound pathogen belonging to coagulase-negative staphylococci. We herein report the first case of a S. lugdunensis isolate carrying the mecA gene in Northern Europe.

Nationell ämneskategori
Klinisk laboratoriemedicin
Identifikatorer
urn:nbn:se:uu:diva-248751 (URN)10.3402/iee.v1i0.8410 (DOI)22957119 (PubMedID)
Tillgänglig från: 2015-04-08 Skapad: 2015-04-08 Senast uppdaterad: 2018-12-12Bibliografiskt granskad

Open Access i DiVA

fulltext(1618 kB)163 nedladdningar
Filinformation
Filnamn FULLTEXT01.pdfFilstorlek 1618 kBChecksumma SHA-512
b7b29ebfd5316563e6440d251628c0a17a715b825e70ef0e3021700f75bd02eb6211fa0d3af12cc0871a88362edabeafb60de4c3fd98cc2edb44367f17d51fe9
Typ fulltextMimetyp application/pdf
Köp publikationen >>

Sök vidare i DiVA

Av författaren/redaktören
Starlander, Gustaf
Av organisationen
Klinisk mikrobiologi
Infektionsmedicin

Sök vidare utanför DiVA

GoogleGoogle Scholar
Totalt: 163 nedladdningar
Antalet nedladdningar är summan av nedladdningar för alla fulltexter. Det kan inkludera t.ex tidigare versioner som nu inte längre är tillgängliga.

isbn
urn-nbn

Altmetricpoäng

isbn
urn-nbn
Totalt: 976 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf