Transcript Antimicrobial susceptibility patterns of Polish invasive isolates of

Antimicrobial susceptibility patterns
of Polish invasive isolates of Neisseria
meningitidis in the years 1997-2006
Marcin Kadłubowski1, Anna Skoczyńska1, Tomasz Wołkowicz2, Waleria Hryniewicz1
1 National Reference Centre for Bacterial Meningitis, Department of Epidemiology and Clinical
Microbiology, National Medicines Institute, Warsaw, Poland
2 Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, Warsaw
University, Warsaw, Poland
INTRODUCTION
RESULTS
Monitoring of antimicrobial susceptibility of invasive bacterial pathogens,
such as Neisseria meningitidis is extremely important for establishment
of therapeutic and prophylactic recommendations. In Poland
antimicrobial susceptibility determination of the leading communityacquired invasive bacterial pathogens has been performed in the
National Reference Centre for Bacterial Meningitis (NRCBM).
More than ninety percent of the isolates studied were fully susceptible to
penicillin. There was no change in penicillin susceptibility pattern despite
the increase in prevalence of serogroup C isolates. Even the occurrence
and dissemination of ST-8/A-4 Cluster meningococci in Poland in 20032005 has not influenced the overall penicillin susceptibility results. There
is still full susceptibility of Polish N. meningitidis invasive isolates to
ceftriaxone, chloramphenicol, rifampin and ciprofloxacin. No significant
changes in MIC50 and MIC90 values of these drugs were observed in
the 10-years study period. MIC50 and MIC90 values for each year are
presented in the following graphs. There is a high percentage of the
isolates non-susceptible to co-trimoxazole and MIC50 as well as MIC90
values of this drug correspond to the resistant phenotype during all the
study period.
The percentages of susceptible, intermediate and resistant isolates were
analysed for each drug and each year. Also, the MIC50 and MIC90
values were calculated. Susceptibility of isolates to antimicrobial drugs
was analysed for major serogroups as well as for particular clonal
complexes.
Penicillin
0,07
0,035
0,06
0,03
0,05
0,025
0,04
MIC50
MIC90
0,03
0,02
0,01
0,01
0,005
0
0
1998
1999
2000
2001
2002
2003
2004
2005
1998
1999
2000
2001
2002
years
years
Chloramphenicol
Rifampin
2,5
2003
2004
2005
2006
0,3
0,25
2
0,2
1,5
MIC50
MIC90
1
MIC50
0,15
MIC90
0,1
0,5
0,05
0
CONCLUSIONS
ACKNOWLEDGEMENTS
MIC90
1997
2006
0
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
1997
1998
1999
2000
2001
years
2002
2003
2004
2005
2006
years
Co-trimoxazole
Ciprofloxacin
9
0,016
8
0,014
7
0,012
0,01
MIC50
0,008
MIC90
0,006
MIC values
6
MIC values
Susceptibility of invasive meningococcal isolates to
antimicrobial drugs has been very stable in Poland.
There is still almost full susceptibility to penicillin, and
this antibiotic is recommended as the drug of choice for
treatment of IMD. In contrast to other European
countries, the emergence of ST-8/A-4 cluster
meningococci has not changed the penicillin
susceptibility pattern in Poland. One hundred percent
susceptibility
of
the
isolates
to
ceftriaxone,
chloramphenicol, rifampin and ciprofloxacin provides a
good coverage for both therapy and chemoprophylaxis
of meningococcal infections. Frequent resistance of
meningococci to co-trimoxazole suggests, that this drug
should not be used neither in treatment, nor in
prophylaxis, and its testing can have only
epidemiological value.
MIC50
0,015
0,02
1997
antimicrobials
Ceftriaxone
MIC values
The analysis was performed on all, over seven-hundred invasive
isolates of N. meningitidis, collected in the NRCBM between 1997 and
2006. Susceptibility to penicillin G, ceftriaxone, chloramphenicol,
rifampin and ciprofloxacin was evaluated by agar dilution method, using
Mueller-Hinton agar supplemented with 5% of defibrinated sheep blood.
For co-trimoxazole the susceptibility was performed by the same
method, using Mueller-Hinton agar with 5% of lysed horse blood. The
Streptococcus pneumoniae ATCC 49619 was used for quality control
purposes. The results were interpreted according to the Clinical and
Laboratory Standards Institute (CLSI) guidelines for N. meningitidis.
MIC values
MATERIALS AND METHODS
MIC50
and
MIC90
values
of
different
for N. meningitidis in Poland, 1997-2006.
MIC values
The aim of this study was to determine the susceptibility of
meningococcal invasive isolates to drugs commonly used in both
therapy and prophylaxis of the invasive meningococcal disease (IMD).
MIC values
AIM
5
MIC50
4
MIC90
3
0,004
2
0,002
1
0
0
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
1997
1998
1999
years
2000
2001
2002
2003
2004
years
Author’s contact details:
Marcin Kadłubowski
National Reference Centre for Bacterial Meningitis,
Dept. of Epidemiology and Clinical Microbiology,
National Medicines Institute
Chelmska 30/34 Street, 00-725 Warsaw
Email: [email protected]
The study was supported by unrestricted grants from Polish Ministry of Health and Ministry of Science. None part of this was supported by any
industrial grant.
The attendance of the presenting author to the Meningitis and Septicaemia Conference was kindly supported by Glaxo Smith Kline Biologicals.
2005
2006