Widespread emergence of methicillin resistance in community-acquired Staphylococcus aureus infections in Denver.
BACKGROUND
Increasing rates of methicillin resistance among out-patient Staphylococcus aureus infections led us to assess the epidemiology and outcome of a local outbreak.


METHODS
A retrospective cohort study of outpatient skin and soft tissue infections due to S aureus in 2003.


RESULTS
From 2002 to mid-2004, the percentage of outpatient S aureus isolates resistant to methicillin increased from 6 to 45%. In multivariate analysis, only male sex and age greater than 18 years were associated with methicillin resistance. Methicillin resistance was common (>15%) among isolates from patients in nearly all subgroups evaluated. Pulsed field gel electrophoresis showed isolates related to USA 300, but methicillin-resistant strains had unusually high rates of quinolone resistance.


CONCLUSIONS
A single strain of methicillin-resistant S aureus is responsible for the increase in skin infections in outpatients without traditional risk factors for infection with an antibiotic-resistant strain. In areas with high rates of methicillin-resistant S aureus outpatient infections, we recommend non-beta-lactam antibiotics for initial treatment of skin and soft tissue infections.
Clancy
Megan J
MJ
Department of Internal Medicine, University of Colorado Health Sciences Center, Denver, CO. USA.
Graepler
Amy
A
Breese
Peter E
PE
Price
Connie S
CS
Burman
William J
WJ
D000293:Adolescent; D000328:Adult; D003120:Colorado / Q000453:epidemiology; D017714:Community-Acquired Infections; D005260:Female; D006801:Humans; D008297:Male; D016106:Methicillin Resistance; D018461:Soft Tissue Infections / Q000453:epidemiology / Q000382:microbiology*; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013207:Staphylococcal Skin Infections / Q000453:epidemiology / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects*; D016896:Treatment Outcome