Download Résistance aux antibiotiques chez les mycoplasmes et les chlamydiae

Résistance aux antibiotiques chez les mycoplasmes et les chlamydiae
C. Bébéar, B. de Barbeyrac, S. Pereyre, C.M. Bébéar
Laboratoire de Bactériologie, EA 3671, Centre national de référence des infections à
chlamydiae, Université Victor Segalen Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux
Cedex.
Tirés à part :
C. Bebear,
voir adresse ci-dessus.
e-mail : [email protected]
Mots-clés : Mycoplasmes, chlamydiae, résistance, tétracyclines, macrolides,
fluoroquinolones.
Antibiotic resistance in mycoplasmas and chlamydiae
C. Bébéar, B. de Barbeyrac, S. Pereyre, C.M. Bébéar
Mycoplasmas and chlamydiae, bacteria involved in respiratory tract and urogenital infections,
differ by their growth requirements, acellular specific media for mycoplasmas, cell culture
methods for chlamydiae. Tetracyclines, macrolides and related antibiotics (MLSKs) and
fluoroquinolones, are active against both microorganisms. However innate resistance to
certain MLSKs are observed in M. hominis (Mh) and Ureaplasma spp. (U spp.), two genital
mycoplasmas. Acquired resistance has been reported in clinical isolates of Mh and U spp.,
and linked to therapeutic failure. It concerns mainly tetracyclines and is due to the presence of
the tet(M) gene. Acquired resistance to macrolides and fluoroquinolones, very rarely observed
in these two species, mainly in immunosuppressed patients, is linked to mutations in the
antibiotic target. For M. pneumoniae, only resistance to macrolides has been reported in a
very small number of clinical isolates, while mutants resistant to fluoroquinolones and
tetracyclines were obtained in vitro. Antibiotic resistance is not documented in M. genitalium.
Acquired resistance is more controversial in chlamydiae. Clinical treatment failures have been
attributed to C. trachomatis strains exhibiting heterotypic multidrug resistance, concerning
only a small number of organisms. Induction of resistance has been observed in vitro but
homotypic stable resistance has been demonstrated only in swine isolates. So heterotypic
stable resistance is perhaps induction of a persistent phenotype refractory to multiple
antibiotics and its responsibility in therapeutic failure is not clear.
Key words: Mycoplasmas, chlamydiae, resistance, tetracyclines, macrolides,
fluoroquinolones.
Antibiotiques 2004 ; 6 : 263-272
Figure 1.M. hominis (Mh) and Ureaplasma spp. colonies (magnificationX170).