Prevalence and demographics of methicillin resistant Staphylococcus aureus in culturable skin and soft tissue infections in an urban emergency department

Christian H Jacobus¹ , Christopher J Lindsell¹ , Sabrina D Leach¹ , Gregory J Fermann¹ , Amy Beth Kressel² and Laura E Rue³

¹Department of Emergency Medicine, University of Cincinnati, Cincinnati, OH, USA

²Division of Infectious Diseases, Department of Medicine, Indiana University, Indianapolis, IN, USA

³University of Kentucky College of Medicine, Lexington, KY, USA

author email corresponding author email

BMC Emergency Medicine 2007, 7:19doi:10.1186/1471-227X-7-19


Published:	31 October 2007

Abstract

Background

The rising incidence of methicillin resistant Staph. aureus (MRSA) infections is a concern for emergency practitioners. While studies have examined MRSA in inpatients, few have focused on emergency department populations. We sought to describe predictors of MRSA skin infections in an emergency department population.

Methods

This was a prospective observational cohort study conducted over three months in 2005. A convenience sample of patients with culturable skin infections presenting to a busy, urban emergency department was enrolled. Demographic and risk factor information was collected by structured interview. The predictive value of each risk factor for MRSA, as identified by culture, was tested using univariable logistic regression, and a multivariable predictive model was developed.

Results

Patients were 43% black, 40% female and mean age was 39 years (SD 14 years). Of the 182 patients with cultures, prevalence of MRSA was 58% (95%CI 50% to 65%). Significant predictors of MRSA were youth, lower body mass index, sexual contact in the past month, presence of an abscess cavity, spontaneous infection, and incarceration. The multivariable model had a C-statistic of 0.73 (95%CI 0.67 to 0.79) with four significant variables: age, group living, abscess cavity, and sexual contact within one month.

Conclusion

In this population of emergency department patients, MRSA skin infection was related to youth, recent sexual contact, presence of abscess, low body mass index, spontaneity of infection, incarceration or contact with an inmate, and group home living.