Community-onset methicillin-resistant Staphylococcus aureus skin and soft-tissue infections: impact of antimicrobial therapy on outcome.
BACKGROUND
Conflicting data exist on the role of antimicrobial therapy for the treatment of uncomplicated community-onset methicillin-resistant Staphylococcus aureus (MRSA) skin and soft-tissue infections (SSTIs).


METHODS
We performed a retrospective cohort study of 492 adult patients with 531 independent episodes of community-onset MRSA SSTIs, which consisted of abscesses, furuncles/carbuncles, and cellulitis, at 2 tertiary care medical centers. The purpose of the study was to determine the impact of active antimicrobial therapy (i.e., the use of an agent to which the organism is susceptible) and other potential risk factors on the outcome for patients with uncomplicated community-onset MRSA SSTIs. Treatment failure was the primary outcome of interest and was defined as worsening signs of infection associated with microbiological and/or therapeutic indicators of an unsuccessful outcome. Bivariate analyses and logistic regression analyses were preformed to determine predictors of treatment failure.


RESULTS
An incision and drainage procedure was performed for the majority of patients. Treatment failure occurred in 45 (8%) of 531 episodes of community-onset MRSA SSTI. Therapy was successful for 296 (95%) of 312 patients who received an active antibiotic, compared with 190 (87%) of 219 of those who did not (P=.001 in bivariate analysis). Use of an inactive antimicrobial agent was an independent predictor of treatment failure on logistic regression analysis (adjusted odds ratio, 2.80; 95% confidence interval, 1.26-6.22; P=.01).


CONCLUSIONS
Our findings suggest that certain patients with SSTIs that are likely caused by MRSA would benefit from treatment with an antimicrobial agent with activity against this organism.
Ruhe
Jörg J
JJ
Division of Infectious Diseases, Department of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA. ruhejorgj@uams.edu
Smith
Nathaniel
N
Bradsher
Robert W
RW
Menon
Anupama
A
D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011336:Probability; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D018461:Soft Tissue Infections / Q000175:diagnosis / Q000188:drug therapy*; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000188:drug therapy; D013207:Staphylococcal Skin Infections / Q000175:diagnosis / Q000188:drug therapy*; D013211:Staphylococcus aureus / Q000187:drug effects; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents