A retrospective analysis of practice patterns in the treatment of methicillin-resistant Staphylococcus aureus skin and soft tissue infections at three Canadian tertiary care centres.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) infections are increasingly being encountered and pose an increasing burden to the health care system in Canada.

Objective: To elucidate and characterize the factors influencing the current MRSA treatment patterns in patients with skin and soft tissue infections (SSTIs) before linezolid became available on the Canadian market.

Methods: A retrospective study collected demographic, treatment and resource use data on patients hospitalized at one of three geographically distinct tertiary care facilities, where MRSA SSTI treatment was initiated with intravenous (IV) vancomycin. Analysis of opportunities for IV-to-oral switch therapy was based on eligibility criteria.

Results: Of 89 patients identified over a 43-month period, the mean (+/-SD) durations of anti-infective treatment and hospitalization were 22.4+/-21 days and 28.9+/-20.8 days, respectively. An infected surgical wound was most common, representing 62.9% of infections. The mean duration of vancomycin treatment was 19.5 days and the mean number of 1 g doses received was 29.0+/-32.9. The majority of patients (55.1%) initiated vancomycin therapy a mean of 5.4+/-8.9 days after confirmation of MRSA. Of the 70% of patients meeting criteria for IV-to-oral switch therapy, only 10% received oral treatment. The most common reason cited for not switching was lack of an effective oral alternative. Analysis of switch therapy criteria found that IV treatment continued for a mean of 13 days despite the appropriateness of the oral route.

Conclusions: Considerable variation exists in treatment patterns for MRSA infections. Improvements in the initiation of therapy and the use of IV-to-oral switch therapy may improve care and reduce the duration of hospitalization for MRSA SSTIs.