Background: Complicated skin and skin structure infections (cSSSIs) result in more than 1 million hospitalizations annually in the United States. Whereas cSSSI treatment guidelines have changed over time, changes in initial antibiotic therapy have not been well described.
Methods: We examined admission records from approximately 100 US hospitals over the period January 1, 2000, to June 30, 2009, to characterize changes in initial antibiotic therapy in patients aged 18 years or older who were hospitalized for cSSSI. Initial antibiotic therapy was defined as all parenteral antibiotics received within 24 hours of admission. Statistical significance of changes in therapy was ascertained using 2-tailed χ2 tests.
Results: The study sample consisted of 22,382 patients hospitalized for cSSSI; most (75%) had acute infections (18%, surgical-site; and 7%, chronic/ulcerative). The use of cefazolin as initial therapy (either alone or as part of a multi-drug regimen) declined markedly, from 32% of all cSSSI admissions in 2000 to 11% in 2009, as did the use of ampicillin-sulbactam (26% to 10%) (both P < 0.01). The use of agents with activity against methicillin-resistant Staphylococcus aureus increased from 30% of all cSSSI admissions in 2000 to 71% in 2009, reflecting an increased use of vancomycin (20% to 58%); the use of agents with activity against Pseudomonas aeruginosa also increased (16% to 28%) (all P < 0.01).
Conclusions: Initial antibiotic therapy for cSSSI has changed substantially in the United States over the past decade, most likely owing to growing concerns about antimicrobial resistance and revised treatment guidelines.