Abstract

One hundred macrolide-resistant staphylococcal isolates from clinically relevant infections in Italy during a 19-month period were studied. Four distinct resistance phenotypes were observed using the triple-disk induction test (erythromycin, clindamycin, telithromycin): the cMLS(B) phenotype (24 isolates); the iMLS(B) phenotype (41 isolates); the MS phenotype (three isolates); and the iMTS phenotype (erythromycin-induced telithromycin resistance) (32 isolates). ermC and ermA genes predominated within erythromycin-resistant Staphylococcus aureus isolates with iMLS(B) phenotype and cMLS(B) phenotype, respectively. Among erythromycin-resistant CoNS isolates, half of the strains showed the iMTS or MS/msrA association, and ermC gene predominated among isolates with MLS(B) phenotype. By pulsed-field gel electrophoresis, high genetic heterogeneity was observed among the isolates studied. Both independent acquisition of macrolide resistance genes and spread of specific resistant clones were observed. Association between certain clonal types and specific types of infection could be detected. To our knowledge, this is the first report on characterization of erythromycin-resistant staphylococci in Italy.

Links

Publisher Full Text

Authors

Gherardi G, De Florio L, Lorino G, Fico L, Dicuonzo G

Institution

Dipartimento di Scienze Biomediche, Università Campus Bio-Medico, Rome, Italy. g.gherardi@unicampus.it

Source

FEMS immunology and medical microbiology 55:1 2009 Jan pg 62-7

MeSH

Anti-Bacterial Agents
Bacterial Proteins
Drug Resistance, Bacterial
Genes, Bacterial
Genotype
Humans
Italy
Macrolides
Methyltransferases
Microbial Sensitivity Tests
Phenotype
Staphylococcal Infections
Staphylococcus

Pub Type(s)

Journal Article

Language

eng

PubMed ID

19076222