Partial excision of the chromosomal cassette containing the methicillin resistance determinant results in methicillin-susceptible Staphylococcus aureus.
We report a detailed characterization of methicillin-susceptible Staphylococcus aureus isolates from five French hospitals negative for both the mecA and the ccrAB loci but positive for the IS431::pUB110::IS431::dcs structure, present in some Staphylococcus cassette chromosome mec (SCCmec) types. The presence of SCCmec-associated elements suggests that this unusual resistant phenotype is due to a partial excision of SCCmec from epidemic methicillin-resistant S. aureus. The hypothesis of a genetic relatedness is strengthened by common sequence and spa types and similar susceptibility patterns.
Donnio
Pierre-Yves
PY
Laboratoire de Bactériologie-Virologie, Centre Hospitalier Universitaire, Rue Henri Le Guilloux, 35033 Rennes, France. pierre-yves.donnio@chu-rennes.fr
Oliveira
Duarte C
DC
Faria
Nuno A
NA
Wilhelm
Nathalie
N
Le Coustumier
Alain
A
de Lencastre
Herminia
H
D002876:Chromosomes, Bacterial; D006801:Humans; D016106:Methicillin Resistance / Q000235:genetics*; D016133:Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics*