title: High Staphylococcus aureus colonization prevalence among patients with skin and soft tissue infections and controls in an urban emergency department.
abstract: Staphylococcus aureus is a commensal species that can also be a formidable pathogen. In the United States, an epidemic of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections has been occurring for the last 15 years. In the context of a study in which we identified patients with skin and soft tissue infections (SSTIs) and randomized them to receive one of two antimicrobial treatment regimens, we assessed S. aureus colonization in the nares, throat, and perianal skin on the day of enrollment and 40 days after therapy. We compared the prevalence of colonization between the SSTI patients and an uninfected control population. A total of 144 subjects and 130 controls, predominantly African American, participated in this study, and 116 returned for a 40-day follow-up visit. Of the SSTI patients, 76% were colonized with S. aureus at enrollment, as were 65% of the controls. Patients were more likely than the controls to be colonized with USA300 MRSA (62/144 [43.1%] versus 11/130 [8.5%], respectively; P < 0.001). The nares were not the most common site of colonization. The colonization prevalence diminished somewhat after antibiotic treatment but remained high. The isolates that colonized the controls were more likely than those in the patients to be methicillin-susceptible S. aureus (MSSA) (74/84 [88.1%] versus 56/106 [52.8%], respectively; P < 0.001). In conclusion, the prevalence of S. aureus colonization among SSTI patients was high and often involved USA300 MRSA. The prevalence diminished somewhat with antimicrobial therapy but remained high at the 40-day follow-up visit. Control subjects were also colonized at a high prevalence but most often with a genetic background not associated with a clinical infection in this study. S. aureus is a commensal species and a pathogen. Plans for decolonization or eradication should take this distinction into account.
authors.affiliation: University of Chicago, Section of Infectious Diseases, Department of Pediatrics, Chicago, Illinois, USA.
authors.forename: Neha
authors.initials: N
authors.lastname: Kumar
authors.affiliation: University of Chicago, Section of Infectious Diseases, Department of Pediatrics, Chicago, Illinois, USA.
authors.forename: Michael Z
authors.initials: MZ
authors.lastname: David
authors.affiliation: University of Chicago, Section of Infectious Diseases, Department of Pediatrics, Chicago, Illinois, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Boyle-Vavra
authors.affiliation: University of Chicago, Section of Infectious Diseases, Department of Pediatrics, Chicago, Illinois, USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Sieth
authors.affiliation: University of Chicago, Section of Infectious Diseases, Department of Pediatrics, Chicago, Illinois, USA rdaum@peds.bsd.uchicago.edu.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Daum
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002353:Carrier State / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009666:Nose / Q000382:microbiology; D010502:Perineum / Q000382:microbiology; D015995:Prevalence; D012867:Skin / Q000382:microbiology; D018461:Soft Tissue Infections / Q000453:epidemiology* / Q000382:microbiology; D013207:Staphylococcal Skin Infections / Q000453:epidemiology* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D014505:Urban Population; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents