surveillance of antibiotic consumption and antibiotic resistance in swedish intensive care units

83 Pages·2007·0.55 MB·English

Linköping University Medical Dissertations No. 1019
SURVEILLANCE OF
ANTIBIOTIC CONSUMPTION
AND ANTIBIOTIC RESISTANCE
IN SWEDISH INTENSIVE CARE UNITS
MARCUS ERLANDSSON
Linköping 2007
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Linköping University Medical Dissertations No. 1019
SURVEILLANCE OF
ANTIBIOTIC CONSUMPTION
AND ANTIBIOTIC RESISTANCE
IN SWEDISH INTENSIVE CARE UNITS
MARCUS ERLANDSSON
Department of Clinical and Experimental Medicine, Division of Infectious Diseases, Faculty of Health Sciences, Linköping University, Sweden
Linköping 2007
Surveillance of Antibiotic Consumption and
Antibiotic Resistance in Swedish Intensive Care Units
© Marcus Erlandsson 2007
All previously published papers, figures and tables are
reprinted with permission from the publishers.
Date of disputation: 2007-10-26
Institution: IKE
ISBN: 978-91-85895-77-9
ISSN: 0345-0082
Art direction: Niklas Ramviken, ENO form
Printed by LiU-Tryck, Linköping, Sweden, 2007

ABSTRACT
INTRODUCTION: Nosocomial infec- in the ICU, and to investigate the emer-
tions remain a major cause of mortal- gence of resistance and transmission of
ity and morbidity. The problem is most Pseudomonas aeruginosa in the ICU
apparent in intensive care units (ICUs). using cluster analysis based on antibio-
Most ICU patients are compromised and grams and genotype data obtained by
vulnerable as a result of disease or se- AFLP.
vere trauma. One in ten people admitted
to hospital is given an antibiotic for in- MATERIAL AND METHODS: In pa-
fection. The risk of acquiring a nosoco- per 1-3, antibiotic consumption data
mial infection in a European ICU is ap- together with bacterial antibiotic resist-
proximately 20%. It is vitally important ance data and specific ICU-demographic
that ways are found to prevent transmis- data were collected from an increasing
sion between patients and personnel, and number of ICUs over the years 1997-
that local hygiene routines and antibiotic 2001. Data from ICUs covering up to
policies are developed. This thesis is a six million out of Sweden’s nine million
holistic work focused particularly on an- inhabitants were included. In paper 4,
timicrobial antibiotic resistance, antibi- the indications for antibiotic prescribing
otic consumption and to some extent on were studied during two weeks in 2000.
hygiene in Swedish ICUs. Paper 5 investigated Pseudomonas aeru-
ginosa isolates in order to detect cross-
AIMS: The general aim of this thesis was transmission with genotype obtained by
to investigate bacterial resistance and AFLP, and antibiogram-based cluster
antibiotic consumption in Swedish ICUs analysis was also performed in order to
and to try to correlate ICU demographic see if this could be a quicker and easier
data with antibiotic consumption and an- substitute for AFLP.
tibiotic resistance. Additional aims were
to investigate on which clinical indica-
tions antibacterial drugs are prescribed
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RESULTS: This thesis has produced CONCLUSION: For the period studied,
three important findings. Firstly, antibi- multidrug resistance in Swedish ICUs
otic consumption in participating ICUs was not a major problem. Signs of cross-
was relatively high during the study pe- transmission with non-multiresistant
riod, and every patient received on aver- bacteria were observed, indicating a
age more than one antimicrobial drug per hygiene problem and identifying sim-
day (I-IV). Secondly, levels of antimi- ple improvements that could be made in
crobial drug resistance seen in S. aureus, patient care guidelines and barrier pre-
E. coli and Klebsiella spp remained low cautions. A need for better follow up of
when data were pooled from all ICUs prescribed antibiotics was evident. With
throughout the study period, despite further surveillance studies and moni-
relatively high antibiotic consumption toring of antibiotics and bacterial resist-
(I-V). Thirdly, the prevalence of antibi- ance patterns in the local setting as well
otic resistance in CoNS and E. faecium, as on a national and international level,
cefotaxime resistance in Enterobacter, some of the strategic goals in the pre-
and ciprofloxacin and imipenem resist- vention and control of the emergence of
ance in P. aeruginosa was high enough antimicrobial-resistant microbes may be
to cause concern. achievable.
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TABLE OF
CONTENTS
ABSTRACT .................................................................................................. 6
TABLE OF CONTENTS ................................................................................ 8
LIST OF PUBLICATIONS ............................................................................ 10
ABBREVIATIONS ....................................................................................... 12
INTRODUCTION ......................................................................................... 14
Nosocomial ICU infections .......................................................................... 15
ICU pathogens .......................................................................................... 16
Antimicrobial drugs .................................................................................... 18
Susceptibility breakpoints ........................................................................... 21
ATC, DDD and DDD ............................................................................. 21
1000
Antimicrobial drug resistance mechanisms, development and spread ............. 21
Surveillance of microbial antibiotic resistance,
antibiotic consumption and nosocomial infections ........................................ 24
Hospital hygiene and factors affecting nosocomial infection rates ................. 24
AIMS .......................................................................................................... 26
MATERIALS AND METHODS .................................................................... 28
Patients and settings ................................................................................ 28
Susceptibility testing and bacterial isolates .................................................. 30
Antibiotic consumption .............................................................................. 30
Laboratory and physiological parameters ..................................................... 31
Questionnaire on ICU characteristics and Infection control ............................ 31
Genotyping of Pseudomonas aeruginosa ..................................................... 31
Detection of Metallo-β-lactamases in Pseudomonas aeruginosa ................... 31
Antibiogram-based cluster analysis of Pseudomonas aeruginosa ................... 32
Statistical methods ..................................................................................... 32
RESULTS ................................................................................................... 34
ICU characteristics and infection control ...................................................... 35
Antibiotic consumption and prescriptions ..................................................... 37
Bacterial species and antibiotic resistance ................................................... 39
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DISCUSSION ............................................................................................ 44
Main findings ............................................................................................. 45
Settings .................................................................................................... 45
Antibiotic consumption .............................................................................. 46
Testing for bacterial antibiotic resistance and breakpoints ............................. 52
Bacterial isolates, antibacterial drug resistance and
the emergence of resistance ..................................................................... 54
Genotyping methods ................................................................................. 57
Validation of antibiogram-based cluster analysis ........................................... 58
Adherence to hospital hygiene procedures, hygiene factors and
infection control measures .......................................................................... 58
Validation of the ICU-STRAMA database .................................................... 60
How to continue the battle against multiresistant
microbes in Swedish ICUs .......................................................................... 61
CONCLUSION ........................................................................................... 64
ACKNOWLEDGEMENTS ........................................................................... 00
REFERENCES ............................................................................................ 70
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LIST OF
PUBLICATIONS
10