title: Novel Multiplex PCR Assay for Detection of Chlorhexidine-Quaternary Ammonium, Mupirocin, and Methicillin Resistance Genes, with Simultaneous Discrimination of Staphylococcus aureus from Coagulase-Negative Staphylococci.
abstract: Methicillin-resistantStaphylococcus aureus(MRSA) is a clinically significant pathogen that is resistant to a wide variety of antibiotics and responsible for a large number of nosocomial infections worldwide. The Agency for Healthcare Research and Quality and the Centers for Disease Control and Prevention recently recommended the adoption of universal mupirocin-chlorhexidine decolonization of all admitted intensive care unit patients rather than MRSA screening with targeted treatments, which raises a serious concern about the selection of resistance to mupirocin and chlorhexidine in strains of staphylococci. Thus, a simple, rapid, and reliable approach is paramount in monitoring the prevalence of resistance to these agents. We developed a simple multiplex PCR assay capable of screeningStaphylococcusisolates for the presence of antiseptic resistance genes for chlorhexidine and quaternary ammonium compounds, as well as mupirocin and methicillin resistance genes, while simultaneously discriminatingS. aureusfrom coagulase-negative staphylococci (CoNS). The assay incorporates 7 PCR targets, including theStaphylococcus16S rRNA gene (specifically detectingStaphylococcusspp.),nuc(distinguishingS. aureusfrom CoNS),mecA(distinguishing MRSA from methicillin-susceptibleS. aureus),mupAandmupB(identifying high-level mupirocin resistance), andqacandsmr(identifying chlorhexidine and quaternary ammonium resistance). Our assay demonstrated 100% sensitivity, specificity, and accuracy in a total of 23 variant antiseptic- and/or antibiotic-resistant control strains. Further validation of our assay using 378 randomly selected and previously well-characterized local clinical isolates confirmed its feasibility and practicality. This may prove to be a useful tool for multidrug-resistantStaphylococcusmonitoring in clinical laboratories, particularly in the wake of increased chlorhexidine and mupirocin treatments.
authors.affiliation: Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, Alberta, Canada.
authors.forename: Jo-Ann
authors.initials: JA
authors.lastname: McClure
authors.affiliation: Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, Alberta, Canada.
authors.forename: Johanna
authors.initials: J
authors.lastname: Zaal DeLongchamp
authors.affiliation: Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, Alberta, Canada.|Department of Pathology & Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada.|Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada.|Department of Medicine, University of Calgary, Calgary, Alberta, Canada.|The Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
authors.forename: John M
authors.initials: JM
authors.lastname: Conly
authors.affiliation: Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, Alberta, Canada kzhang@ucalgary.ca.|Department of Pathology & Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada.|Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada.|Department of Medicine, University of Calgary, Calgary, Alberta, Canada.|The Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Kunyan
authors.identifier: 0000-0003-1078-6011
authors.initials: K
authors.lastname: Zhang
mesh_terms: D000900:Anti-Bacterial Agents; D002710:Chlorhexidine / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D005798:Genes, Bacterial; D006801:Humans; D008712:Methicillin / Q000494:pharmacology; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D016712:Mupirocin / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000175:diagnosis* / Q000382:microbiology*; D013210:Staphylococcus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents; D000644:Quaternary Ammonium Compounds; D012336:RNA, Ribosomal, 16S; D016712:Mupirocin; D008712:Methicillin; D002710:Chlorhexidine
keywords: MRSA; antiseptic; chlorhexidine; coagulase-negative staphylococci; methicillin; multiplex PCR; mupirocin; quaternary ammonium; resistance