Baxter, C.

Denning, D.

Ireland, D.

Jones, A.

Thornback, J.

Webb, A. K.

Jones, A.M.

Webb, A.K.

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5. Microbiology S43
171 Staphylococcus aureus with decreased susceptibility to
glycopeptides in cystic ﬁbrosis patients
A. Filleron1, R. Chiron2, H. Jean-Pierre1,3, M. Reverdy4, F. Counil2,
L. Aleyrangues1, E. Jumas-Bilak1,3, H. Marchandin1,3. 1Laboratoire de
Bacte´riologie, CHU, Montpellier, France; 2CRCM, CHU, Montpellier, France;
3EA3755, Faculte´ de Pharmacie, Montpellier, France; 4Centre National de
Re´fe´rence des staphylocoques, Lyon, France
Cystic ﬁbrosis (CF) patients are frequently colonized or infected with Staphylo-
coccus aureus. Recent reports suggest modiﬁcations in isolates epidemiology with
strains displaying particular virulence or antibiotic resistance pattern.
We describe the clinical and microbiological features of 2 cases of hetero-
Glycopeptide-Intermediate resistance S. aureus (h-GISA) isolation in CF patients,
one of them having received long-term teicoplanin therapy. The strains were
characterized by antibiotyping, population analysis, determination of SCCmec
(1 me´ticillino-resistant strain) and agr types, as well as Sequence Type. They were
unrelated to each other. We discuss their epidemiology and pathogenicity.
We currently investigate a collection of 150 strains of S. aureus for its suscepti-
bility to glycopeptides. In particular, a new Etest vancomycin-teicoplanin strip for
detection of GISA/h-GISA is evaluated. Preliminary results showed that the method
failed to detect the two previous h-GISA isolates whereas the reference strain Mu3
was correctly categorized.
S. aureus strains with decreased susceptibility to glycopeptides were previously
associated to broncho-pulmonary exacerbation, failure of glycopeptides therapy
and clonal spread. Although very rarely reported during CF, these strains may
be underestimated in CF patients due to their detection difﬁculty despite the new
tools proposed in routine practice of microbiological laboratories.
172 Characteristics of Staphylococcus aureus small colony variants
(SCV) in CF patients
S. Yagci1, G. Hascelik1, E. Yalcin2, D. Dogru2, B. Sener1, U. Ozcelik2,
N. Kiper2. 1Clinical Microbiology, Hacettepe University, Ankara, Turkey;
2Pediatric Pulmonology, Hacettepe University, Ankara, Turkey
Background: S. aureus SCV are usually associated with persistence in CF airways.
This study was aimed to determine the prevalence and antibiotic susceptibilities of
S. aureus SCV and the demographic characteristics of SCV positive patients.
Methods: Sputum and throat swab specimens of 248 patients were examined during
February 2007-January 2008. SCV suspected colonies were conﬁrmed by latex
agglutination, coagulase test and S.aureus nucA PCR. Antibiotic susceptibilities
were tested by microdilution method. Medical records were reviewed for data
collection of SCV positive cases.
Results: A total of 48 SCV were detected in 20 of the 248 patients (8.1%). All
the suspected SCV colonies were conﬁrmed as S.aureus. The mean age of SCV
isolated patients was 14.4 years. SCV prevalence was signiﬁcantly higher above
age 11. Cocolonization with P.aeruginosa was 55.6% in SCV positive patients
whereas it was 28.6% in non-SCV patients (p< 0.05). Prior antibiotic use of the
SCV positive patients were most frequently beta-lactam beta-lactamase inhibitor
combinations (12/19) and ciproﬂoxacin (12/19). Resistance rates for SCV and
their normal S.aureus counterparts were 10.4%, 0% for oxacillin; 6.3%, 0% for
gentamicin; 14.6%, 18.2% for ciproﬂoxacin; 16.7%, 3% for TMP-SXT; respectively.
MIC values for tigecycline were higher in SCV isolates. No resistance was detected
for vancomycin and linezolid.
Conclusion: Since SCVs are more resistant to antibiotics and have a tendency to
resist intracellular killing, it is important to consider and report S.aureus SCVs
in CF. Presence of P.aeruginosa in the CF airways might be considered as a
predisposing factor for evolution towards S. aureus SCV.
173 Staphylococcus aureus small colony variants (SASCVs) in CF pts
treated at Children’s Memorial Health Institute, Warsaw, Poland
H. Dmenska1, K. Semczuk2, K. Dzierzanowska-Fangrat2, D. Dzierzanowska2.
1Lung Physiology Dept., The Children’s Memorial Health Institute, Warsaw,
Poland; 2Dept. of Clinical Microbiology and Immunology, The Children’s
Memorial Health Institute, Warsaw, Poland
The aim of the study was to determine the frequency of spontaneous and inducible
SCV formation in SA isolates obtained from CF pts, to determine antibiotic
susceptibility of natural SA (NSA) and SASCV on the basis of minimal inhibitory
concentration (MIC) and to determine possible effect of antibiotic treatments in
selection of these strains.
Material and Methods: Total of 279 SA strains isolated from 33 CF pts (14
boys, 19 girls, mean age 7.5 years) and 40 isolates from the upper airway from
non CF-pts were analysed. The study lasted 8 years. The medical records provided
the information about the antibiotic therapy: betalactams 36%, macrolides 21%,
ﬂuorochinolones 14%, aminoglycosides 13% (mainly in nebulisation).
Results: SASCV were obtained from 13% isolates from 5 pts. In 3/5 pts SASCV
and NSA were isolated simultaneously. In 4/5 pts P. aeruginosa (PA) colonisation
was found. 4/5 pts received aminoglicosides before the study. SASCV presented
decreased susceptibility to some antibiotics in comparison to NSA (MIC SASV
vs MIC NSA): gentamicin (32 vs O.75mg/L), erythromycin (256 vs 0.5mg/L),
ciproﬂoxacin (8 vs 0.75mg/L). In the subinhibitory gentamicin concentration SA
strains from CF pts formed SCVs more frequently (55%) than isolates from non-CF
pts (20%).
Conclusions: The characteristic feature of SA strains, persistently colonizing the
CF pts’ airways is the formation of SCV. The SASCV formation is affected by
the presence of PA. The study has also shown that SASCV formation in CF pts
may be associated with inhaled aminoglycoside treatment. SASCV’s susceptibility
to antibiotics is decreased.
174 Diversity of Candida spp in adult CF patients
C. Baxter1,2, A.M. Jones1, A.K. Webb1, J. Thornback3, D. Ireland3,
D. Denning2,3. 1Manchester Adult CF Unit, Wythenshawe Hospital, Manchester,
United Kingdom; 2Education and Research Centre, Wythenshawe Hospital,
Manchester, United Kingdom; 3Myconostica Ltd, Manchester, United Kingdom
Introduction: Pulmonary infections in Cystic Fibrosis (CF) are predominantly
bacterial but the incidence and diversity of fungi as lung pathogens is increasing.
Some fungi such as Aspergillus are known to cause signiﬁcant morbidity in CF but
other fungi have not yet been evaluated for their prevalence or clinical impact. This
prospective, cross-sectional observational study set out to determine the prevalence
and speciation of Candida spp in an adult CF cohort.
Methods: Sputum samples were collected from 36 patients attending the Manch-
ester Adult CF Unit. After homogenization with Dithiothreiotol, 10 mL of sputum
was inoculated onto sabauroud (SAB) agar and chrome agar then incubated for
72 hours. Yeast colonies were sub-cultured into germ cell tubes for further micro-
scopic identiﬁcation. Remaining sputum was processed in a molecular laboratory
using the MycXtra™ (Myconostica Ltd) fungal DNA extraction kit. Extracted DNA
was stored for Candida DNA microarray analysis.
Results: SAB agar cultured yeast in 24 of 36 samples (67%). Chrome agar and germ
cell culture identiﬁed >1 Candida species in 7 of the 24 positive samples. 4 plates
had species that were unidentiﬁable. Of those colonies identiﬁed the following
species were found: Candida albicans/dublinensis 22, Candida glabrata 5, Candida
tropicalis 1, Candida parapsilosis 1. These species are currently being tested for
antifungal resistance. As there are unidentiﬁed species, we are currently performing
molecular identiﬁcation with a Candida DNA microarray.
Conclusion: There is a wide diversity of Candida spp in adult CF sputum. Fungal-
bacterial interactions are important. More research is required into the clinical
relevance of these yeasts.


Diversity of Candida spp in adult CF patients 

Introduction Pulmonary infections in Cystic Fibrosis (CF) are predominantly bacterial but the incidence and diversity of fungi as lung pathogens is increasing. Some fungi such as Aspergillus are known to cause significant morbidity in CF but other fungi have not yet been evaluated for their prevalence or clinical impact. This prospective, cross-sectional observational study set out to determine the prevalence and speciation of Candida spp in an adult CF cohort. Methods Sputum samples were collected from 36 patients attending the Manchester Adult CF Unit. After homogenization with Dithiothreiotol, 10µL of sputum was inoculated onto sabauroud (SAB) agar and chrome agar then incubated for 72 hours. Yeast colonies were sub-cultured into germ cell tubes for further microscopic identification. Remaining sputum was processed in a molecular laboratory using the MycXtra™ (Myconostica Ltd) fungal DNA extraction kit. Extracted DNA was stored for Candida DNA microarray analysis. Results SAB agar cultured yeast in 24 of 36 samples (67%). Chrome agar and germ cell culture identified &gt; 1 Candida species in 7 of the 24 positive samples. 4 plates had species that were unidentifiable. Of those colonies identified the following species were found: Candida albicans/dublinensis 22, Candida glabrata 5, Candida tropicalis 1, Candida parapsilosis 1. These species are currently being tested for antifungal resistance. As there are unidentified species we are currently performing molecular identification with a Candida DNA microarray. Conclusion There is a wide diversity of Candida spp in adult CF sputum. Fungal-bacterial interactions are important. More research is required into the clinical relevance of these yeasts

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Diversity of Candida spp in adult CF patients

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Diversity of Candida spp in adult CF patients

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