title: An investigation of antibiotic susceptibility to empiric therapy for community-associated methicillin-resistant Staphylococcus aureus.
abstract: OBJECTIVE
  To analyze antibiotic susceptibility patterns of community-associated methicillin-resistant Staphylococcus aureus (MRSA) isolates obtained from skin and soft tissue infections among Wisconsin outpatients.
  
  
  METHODS
  Retrospective genotype testing.
  
  
  METHODS
  Isolates were forwarded to the Wisconsin State Laboratory of Hygiene and Marshfield Labs from clinical laboratories throughout Wisconsin.
  
  
  METHODS
  MRSA isolates submitted during April, 2010-February, 2012 underwent genotype analysis using pulsed-field gel electrophoresis. Antibiotic susceptibility patterns were determined for all isolates identified by electrophoresis subtyping as strain type USA300, and pattern comparisons were made by public health region.
  
  
  RESULTS
  Among 835 MRSA isolates submitted, 217 (26%) were genotyped. Of these, 152 (70%) were USA300 MRSA. Among the 152 USA300 isolates, 95% were susceptible to clindamycin and 99% were susceptible to tetracycline and trimethoprim-sulfamethoxazole. The proportion of clindamycin-susceptible isolates from the southern region was significantly lower when compared to the other 4 regions combined (P = 0.03). One southern region clindamycin-resistant isolate was also resistant to trimethoprim-sulfamethoxazole.
  
  
  CONCLUSIONS
  USA300 MRSA was the predominant strain isolated from outpatient skin and soft tissue sites. Antibiotic susceptibility patterns among Wisconsin USA300 MRSA isolates are similar to patterns found in national studies. Local providers should continue to follow national practice guidelines for treatment of outpatient skin infections. A cluster of 4 clindamycin-resistant isolates and 1 trimethoprim-sulfamethoxazole resistant isolate was detected in the southern region, warranting continued surveillance for antibiotic resistance among community-associated MRSA isolates.
authors.forename: Kami
authors.initials: K
authors.lastname: Harless
authors.forename: Gwen
authors.initials: G
authors.lastname: Borlaug
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Monson
authors.forename: Mary E
authors.initials: ME
authors.lastname: Stemper
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Davis
authors.forename: Ann E
authors.initials: AE
authors.lastname: Abing
authors.forename: Jared F
authors.initials: JF
authors.lastname: Shelerud
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017714:Community-Acquired Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D014922:Wisconsin / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents