title: Risk factors for persistent carriage of methicillin-resistant Staphylococcus aureus.
abstract: We determined risk factors associated with persistent carriage of methicillin-resistant Staphylococcus aureus (MRSA) among 102 patients enrolled in a double-blind, placebo-controlled trial of nasally administered mupirocin ointment. MRSA decolonization was unsuccessful in 77 (79%) of 98 patients who met the criteria for evaluation. By univariate analysis, 4 variables were found to be associated with persistent MRSA colonization (P < .1 for all 4): absence of mupirocin treatment, previous fluoroquinolone therapy, > or = 2 MRSA-positive body sites, and low-level mupirocin resistance. After multivariable Cox proportional hazards modeling, the presence of > or = 2 positive body sites (adjusted hazard ratio [AHR], 1.7; 95% confidence interval [CI], 1.0-2.9) and previous receipt of a fluoroquinolone (AHR, 1.8; 95% CI, 1.0-3.3) were independently associated with MRSA persistence, whereas nasal mupirocin tended to confer protection (AHR, 0.6; 95% CI, 0.4-1.0). Low-level mupirocin resistance was observed in 9 genotypically different MRSA strains and was not independently associated with chronic MRSA carriage (AHR, 1.5; 95% CI, 0.9-2.5). Our findings suggest that multisite MRSA carriage and previous receipt of a fluoroquinolone are independent risk factors for persistent MRSA colonization.
authors.affiliation: Infection Control Program, University Hospitals of Geneva, Geneva, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Harbarth
authors.forename: N
authors.initials: N
authors.lastname: Liassine
authors.forename: S
authors.initials: S
authors.lastname: Dharan
authors.forename: P
authors.initials: P
authors.lastname: Herrault
authors.forename: R
authors.initials: R
authors.lastname: Auckenthaler
authors.forename: D
authors.initials: D
authors.lastname: Pittet
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002353:Carrier State / Q000188:drug therapy / Q000382:microbiology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D016106:Methicillin Resistance; D008875:Middle Aged; D016712:Mupirocin / Q000627:therapeutic use*; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D016712:Mupirocin