Tetracyclines as an oral treatment option for patients with community onset skin and soft tissue infections caused by methicillin-resistant Staphylococcus aureus

Few data exist on the clinical utility of the expanded-spectrum tetracyclines doxycycline and minocycline for the treatment of community-associated methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infections (SSTI). We performed a retrospective cohort study of 276 patients who presented with 282 episodes of MRSA SSTI to the emergency room or outpatient clinic at two tertiary medical centers between October 2002 and February 2007. The median percentage of patients infected with MRSA strains that were susceptible to tetracycline was 95%. Time zero was defined as the time of the first incision and drainage procedure or, if none was performed, the time of the first positive wound culture. The median patient age was 48 years. Abscesses constituted the majority of clinical presentations (75%), followed by furuncles or carbuncles (13%) and cellulitis originating from a purulent focus of infection (12%). A total of 225 patients (80%) underwent incision and drainage. Doxycycline or minocycline was administered in 90 episodes (32%); the other 192 SSTI were treated with beta-lactams. Treatment failure, defined as the need for a second incision and drainage procedure and/or admission to the hospital within at least 2 days after time zero, was diagnosed in 28 episodes (10%) at a median of 3 days after time zero. On logistic regression analysis, receipt of a P-lactam agent was the only clinical characteristic associated with treatment failure (adjusted odds ratio, 3.94; 95% confidence interval, 1.28 to 12.15; P = 0.02). The expanded-spectrum tetracyclines appear to be a reasonable oral treatment option for patients with community onset MRSA SSTI in areas where MRSA strains are susceptible to the tetracyclines.