Distribution of antiseptic resistance genes qacA, qacB, and smr in methicillin-resistant Staphylococcus aureus isolated in Toronto, Canada, from 2005 to 2009

Jean Longtin; Christine Seah; Krystal Siebert; Allison McGeer; Andrew Simor; Yves Longtin; Donald E Low; Roberto G Melano

doi:10.1128/AAC.01707-10

Distribution of antiseptic resistance genes qacA, qacB, and smr in methicillin-resistant Staphylococcus aureus isolated in Toronto, Canada, from 2005 to 2009

Antimicrob Agents Chemother. 2011 Jun;55(6):2999-3001. doi: 10.1128/AAC.01707-10. Epub 2011 Mar 14.

Authors

Jean Longtin¹, Christine Seah, Krystal Siebert, Allison McGeer, Andrew Simor, Yves Longtin, Donald E Low, Roberto G Melano

Affiliation

¹ Infectious Disease Research Center, Laval University, 2750 Laurier Blvd., Quebec City, Quebec G1V 4G2, Canada. jean.longtin@CRCHUQ.ULaval.ca

Abstract

Decreased susceptibility to chlorhexidine gluconate (CHDN) in methicillin-resistant Staphylococcus aureus (MRSA) is associated with the qacA, qacB, and smr genes, encoding efflux pumps. A total of 334 MRSA isolates were collected from two Canadian intensive care units between 2005 and 2009. We identified the qacAB genes in 7 strains (2%; 2 qacA genes and 5 qacB genes) and the smr gene in 23 (7%) strains. CHDN minimal bactericidal concentrations were slightly higher for strains harboring smr genes.

MeSH terms

Anti-Infective Agents, Local / pharmacology*
Antiporters / genetics*
Bacterial Proteins / genetics*
Canada
Chlorhexidine / analogs & derivatives*
Chlorhexidine / pharmacology
Membrane Transport Proteins / genetics*
Methicillin-Resistant Staphylococcus aureus / drug effects*
Methicillin-Resistant Staphylococcus aureus / genetics
Time Factors

Substances

Anti-Infective Agents, Local
Antiporters
Bacterial Proteins
Membrane Transport Proteins
QacB protein, Staphylococcus aureus
small multidrug-resistance pump, Staphylococcus aureus
qacA protein, Staphylococcus aureus
chlorhexidine gluconate
Chlorhexidine