Chlorhexidine and Mupirocin Susceptibilities of Methicillin-Resistant Staphylococcus aureus from Colonized Nursing Home Residents
Open Access
- 1 January 2013
- journal article
- Published by American Society for Microbiology in Antimicrobial Agents and Chemotherapy
- Vol. 57 (1), 552-558
- https://doi.org/10.1128/aac.01623-12
Abstract
Chlorhexidine and mupirocin are used in health care facilities to eradicate methicillin-resistant Staphylococcus aureus (MRSA) carriage. The objective of this study was to assess the frequency of chlorhexidine and mupirocin resistance in isolates from nares carriers in multiple nursing homes and to examine characteristics associated with resistance. Nasal swab samples were collected from approximately 100 new admissions and 100 current residents in 26 nursing homes in Orange County, CA, from October 2008 to May 2011. MRSA isolates were tested for susceptibility by using broth microdilution, disk diffusion, and Etest; for genetic relatedness using pulsed-field gel electrophoresis; and for qac gene carriage by PCR. Characteristics of the nursing homes and their residents were collected from the Medicare Minimum Data Set and Long-Term Care Focus. A total of 829 MRSA isolates were obtained from swabbing 3,806 residents in 26 nursing homes. All isolates had a chlorhexidine MIC of ≤4 μg/ml. Five (0.6%) isolates harbored the qacA and/or qacB gene loci. Mupirocin resistance was identified in 101 (12%) isolates, with 78 (9%) isolates exhibiting high-level mupirocin resistance (HLMR). HLMR rates per facility ranged from 0 to 31%. None of the isolates with HLMR displayed qacA or qacB , while two isolates carried qacA and exhibited low-level mupirocin resistance. Detection of HLMR was associated with having a multidrug-resistant MRSA isolate (odds ratio [OR], 2.69; P = 0.004), a history of MRSA (OR, 2.34; P < 0.001), and dependency in activities of daily living (OR, 1.25; P = 0.004). In some facilities, HLMR was found in nearly one-third of MRSA isolates. These findings may have implications for the increasingly widespread practice of MRSA decolonization using intranasal mupirocin.Keywords
This publication has 34 references indexed in Scilit:
- Predicting High Prevalence of Community Methicillin-Resistant Staphylococcus aureus Strains in Nursing HomesInfection Control & Hospital Epidemiology, 2013
- MupB, a New High-Level Mupirocin Resistance Mechanism in Staphylococcus aureusAntimicrobial Agents and Chemotherapy, 2012
- Successful strategies for high participation in three regional healthcare surveys: an observational studyBMC Medical Research Methodology, 2011
- Activity of Ceftaroline and Epidemiologic Trends in Staphylococcus aureus Isolates Collected from 43 Medical Centers in the United States in 2009Antimicrobial Agents and Chemotherapy, 2011
- Association of High-Level Mupirocin Resistance and Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus at an Academic Center in the Midwestern United StatesJournal of Clinical Microbiology, 2011
- Emergence of Resistance among USA300 Methicillin-Resistant Staphylococcus aureus Isolates Causing Invasive Disease in the United StatesAntimicrobial Agents and Chemotherapy, 2010
- Phenotypic and molecular characterization of Staphylococcus aureus isolates expressing low- and high-level mupirocin resistance in Nigeria and South AfricaBMC Infectious Diseases, 2009
- Prevalence of methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii in a long-term acute care facilityAmerican Journal of Infection Control, 2008
- Shea/Apic Guideline: Infection Prevention and Control In The Long-Term Care FacilityInfection Control & Hospital Epidemiology, 2008
- Epidemiology ofStaphylococcus aureusColonization in Nursing Home ResidentsClinical Infectious Diseases, 2008