Abstract | AIMS: We report the analysis of genetic determinants conferring resistance to pristinamycin in Staphylococcus epidermidis strains and epidemiology typing of these strains by pulsed-field gel electrophoresis. METHODS AND RESULTS: Staphylococcus epidermidis (346 isolates) were searched for strains with pristinamycin resistance. Pristinamycin-resistant strains (seven isolates) were isolated in five patients with haematological cancer in the Bone Marrow Transplant Centre of Tunisia in 2002. Resistance to pristinamycin was observed in 2% of isolates. The seven pristinamycin-resistant strains shared resistance to oxacillin (MIC = 8-512 microg ml(-1)), gentamicin (MIC = 16-512 microg ml(-1)), erythromycin (MIC > 1024 microg ml(-1)), lincomycin (MIC > 1024 microg ml(-1)), pristinamycin (MIC = 4-16 microg ml(-1)) and rifampin (MIC = 128-256 microg ml(-1)). erm genes were amplified: ermA from six strains and ermC from one. vga gene encoding streptogramins A resistance ( pristinamycin résistance) was amplified from all strains and typed as vgaA by analysis after electrophoresis of restriction profiles of vga amplicons (two fragments with Sau3A of 164 and 378 bp; one fragment with EcoRI). Pulsed-field gel electrophoresis (PFGE) of SmaI chromosomal DNA digests of the seven S. epidermidis isolates divided them into two distinct pattern types: pulsed-field type A (classified from A1 to A6 subtypes) and type B. The six strains harbouring ermA genes belonged to the PFGE type A while the strain harbouring ermC genes belonged to the PFGE type B. We characterized an epidemic strain carrying the vgaA and ermA genes responsible for the outbreak. CONCLUSIONS: Two clones of pristinamycin-resistant S. epidermidis were isolated in our patients. One of them, isolated in all patients, had expanded over six months suggesting acquisition by cross-contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: Increasing isolation of pristinamycin resistant S. epidermidis strains is an alarming indicator of nosocomial dissemination. The vector will be determined to establish a system of epidemiological surveillance.
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Authors | W Achour, O Bouchami, S Galopin, R Leclercq, A Ben Hassen |
Journal | Letters in applied microbiology
(Lett Appl Microbiol)
Vol. 46
Issue 3
Pg. 358-63
(Mar 2008)
ISSN: 1472-765X [Electronic] England |
PMID | 18194160
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Anti-Bacterial Agents
- Bacterial Proteins
- DNA Primers
- Pristinamycin
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Topics |
- Anti-Bacterial Agents
(pharmacology)
- Bacterial Proteins
(genetics)
- Bone Marrow Transplantation
- DNA Primers
- Drug Resistance, Bacterial
(genetics)
- Electrophoresis, Gel, Pulsed-Field
- Hematologic Neoplasms
(complications)
- Humans
- Microbial Sensitivity Tests
- Polymerase Chain Reaction
- Pristinamycin
(pharmacology)
- Sequence Analysis, DNA
- Staphylococcal Infections
(epidemiology, microbiology)
- Staphylococcus epidermidis
(classification, drug effects, genetics, isolation & purification)
- Tunisia
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