Trimethoprim-Sulfamethoxazole or Clindamycin for Community-Associated MRSA (CA-MRSA) Skin Infections

Abstract

Background: In the United States, community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as the predominant cause of skin infections. Trimethoprim-sulfamethoxazole (TMP-SMX) and clindamycin are often used as first-line treatment options, but clinical data are lacking.Methods: We conducted a retrospective cohort study of outpatients with skin and soft tissue infections managed from July 1 to December 31, 2006. Patients younger than 18 years of age were excluded, as were those who had no clinical admission or progress notes; were hospitalized within the 90 days before admission; were hospitalized with polymicrobial, surgical site, catheter-related, or diabetic foot infections; or were discharged to places other than home. Patient demographics, comorbidities, diagnoses, cultures, prescribed antibiotics, susceptibilities, surgical procedures, and health outcomes were extracted from electronic medical records. Patients were divided in 2 cohorts for further analysis: TMP-SMX and clindamycin. The primary study outcome was composite failure defined as an additional positive MRSA culture from any site 5 to 90 days after treatment initiation or an additional intervention during a subsequent outpatient or inpatient visit. Baseline characteristics and failure rates were compared using

Dose of Trimethoprim-Sulfamethoxazole To Treat Skin and Skin Structure Infections Caused by Methicillin-Resistant Staphylococcus aureus

“…In the absence of these data, we are unable to comment on whether the higher dose of TMP/SMX was truly unnecessary among these patients with MRSA SSTIs. The overall rate of clinical resolution (73.9%) among patients treated with oral TMP/SMX in this study is comparable to that in the study by Cenizal et al (1) and higher than the 61% reported in the study by Frei et al (3) Trimethoprim-sulfamethoxazole does appear to be an effective drug in the treatment of SSTIs caused by MRSA, and earlier studies have shown that the drug is at least as effective as other available oral antimicrobial choices such as doxycycline (1) or clindamycin (3,4). The study by Rajendran et al (9) reported a high placebo response rate of up to 90.5% in patients with uncomplicated skin abscesses that were surgically drained.…”

“…It is interesting that 43% of the patients treated with TMP/SMX in this study but only 3% of the patients in an earlier previous retrospective observational cohort study (3) conducted within the same population base during the year 2006 received the higher dose (320/1,600 mg twice daily), potentially indicating increased popularity of the higher dose. Recent studies that evaluated TMP/SMX for the treatment of MRSA SSTIs have used either the 160/800-mg twice-daily dose (3,4) or the 320/ 1,600-mg twice-daily dose (6,11). None of these previous studies evaluated whether a higher dose of TMP/SMX led to greater clinical resolution.…”

CA-MRSA: Epidemiology of a Pathogen of a Great Concern

“…However, in another study with patients affected by CA-MRSA treated with trimethoprim/sulfamethoxazole, clindamycin and cephalexin resulted in a treatment failure rate of 26%, 25% and 33%, respectively. In addition, patients who received the drainage of abscesses in addition to antibiotic therapy had lower rates of treatment failure (25%) than patients who received only incision and drainage (60%) (Frei et al, 2010).…”

This Issue: International Issues, Infectious Diseases, Medical Liability, and Medical Home Ideas

“…This type of research by a family medicine research network has been not yet reported, but it could be highly valuable to health care in the United States, and it represents excellent teamwork between family physicians and basic science researchers. For another infectious illness, see Frei et al's 13 retrospective cohort study about the treatment of community-associated, methicillinresistant Staphylococcus aureus infection: should it be trimethoprim-sulfamethoxazole or clindamycin? The major conclusion is that incision and drainage is very important but the antibiotic choice is less so.…”