title: Fluoroquinolone Impact on Nasal Methicillin-Resistant and Methicillin-Sensitive Staphylococcus aureus Colonization Durations in Neurologic Long-Term-Care Facilities.
abstract: Staphylococcus aureus nasal carriage is a risk factor for subsequent infection. Estimates of colonization duration vary widely among studies, and factors influencing the time to loss of colonization, especially the impact of antibiotics, remain unclear. We conducted a prospective study on patients naive for S. aureus colonization in 4 French long-term-care facilities. Data on nasal colonization status and potential factors for loss of colonization were collected weekly. We estimated methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) colonization durations using the Kaplan-Meier method and investigated factors for loss of colonization using shared-frailty Cox proportional hazards models. A total of 285 S. aureus colonization episodes were identified in 149 patients. The median time to loss of MRSA or MSSA colonization was 3 weeks (95% confidence interval, 2 to 8 weeks) or 2 weeks (95% confidence interval, 2 to 3 weeks), respectively. In multivariable analyses, the methicillin resistance phenotype was not associated with S. aureus colonization duration (P = 0.21); the use of fluoroquinolones (hazard ratio, 3.37; 95% confidence interval, 1.31 to 8.71) and having a wound positive for a nonnasal strain (hazard ratio, 2.17; 95% confidence interval, 1.15 to 4.07) were associated with earlier loss of MSSA colonization, while no factor was associated with loss of MRSA colonization. These results suggest that the methicillin resistance phenotype does not influence the S. aureus colonization duration and that fluoroquinolones are associated with loss of MSSA colonization but not with loss of MRSA colonization.
authors.affiliation: Institut Pasteur, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France INSERM, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France Université Versailles St-Quentin, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Montigny le Bretonneux, France clotilde.couderc@gmail.com didier.guillemot@pasteur.fr.
authors.forename: Clotilde
authors.initials: C
authors.lastname: Couderc
authors.affiliation: Institut Pasteur, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France INSERM, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France Université Versailles St-Quentin, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Montigny le Bretonneux, France.
authors.forename: Anne C M
authors.initials: AC
authors.lastname: Thiébaut
authors.affiliation: AP-HP, Hôpital Raymond-Poincaré, Garches, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Lawrence
authors.affiliation: Université Lyon 1, International Center for Infectiology Research (CIRI), Lyon, France INSERM, U1111 International Center for Infectiology Research (CIRI), Lyon, France École Normale Supe´rieure de Lyon, International Center for Infectiology Research (CIRI), Lyon, France CNRS, UMR 5308 International Center for Infectiology Research (CIRI), Lyon, France Hospices Civils de Lyon, Centre National de Référence des Staphylocoques, Bron, France.
authors.forename: Coralie
authors.initials: C
authors.lastname: Bouchiat
authors.affiliation: AP-HP, Hôpital Raymond-Poincaré, Garches, France Université Versailles St-Quentin, U1173, Saint-Quentin-en-Yvelines, France INSERM, U1173, Montigny le Bretonneux, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Herrmann
authors.affiliation: Institut Pasteur, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France INSERM, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France Université Versailles St-Quentin, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Montigny le Bretonneux, France AP-HP, Hôpital Raymond-Poincaré, Garches, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Salomon
authors.affiliation: Institut Pasteur, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France INSERM, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Paris, France Université Versailles St-Quentin, UMR 1181 Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases (B2PHI), Montigny le Bretonneux, France AP-HP, Hôpital Raymond-Poincaré, Garches, France clotilde.couderc@gmail.com didier.guillemot@pasteur.fr.
authors.forename: Didier
authors.initials: D
authors.lastname: Guillemot
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015169:Colony Count, Microbial; D005260:Female; D024841:Fluoroquinolones / Q000627:therapeutic use*; D006801:Humans; D007326:Institutionalization; D008134:Long-Term Care; D008297:Male; D016106:Methicillin Resistance; D055624:Methicillin-Resistant Staphylococcus aureus; D008875:Middle Aged; D009296:Nasal Cavity / Q000187:drug effects / Q000382:microbiology; D019636:Neurodegenerative Diseases / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D010641:Phenotype; D016016:Proportional Hazards Models; D011446:Prospective Studies; D013203:Staphylococcal Infections / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones