Active identification of patients who are methicillin-resistant Staphylococcus aureus colonized is not associated with longer duration of vancomycin therapy

Am J Infect Control. 2017 Oct 1;45(10):1081-1085. doi: 10.1016/j.ajic.2017.04.011. Epub 2017 Jun 16.

Abstract

Background: Excessive prescribing of vancomycin among patients admitted to inpatient wards is a challenge for antimicrobial stewardship programs, especially in the setting of expanded screening programs for methicillin-resistant Staphylococcus aureus (MRSA). Studies examining factors associated with longer duration of vancomycin use are limited.

Methods: We conducted a retrospective cohort study to assess the impact of universal MRSA admission screening on duration of vancomycin use at the VA Boston Healthcare System during the period from January 2013-November 2015.

Results: A total of 2,910 patients were administered intravenous vancomycin during the study period. A clinical culture positive for MRSA was strongly associated with vancomycin administration lasting >72 hours (odds ratio [OR], 2.72; 95% confidence interval [CI], 1.86-3.97; P < .001). After controlling for clinical culture results, admission MRSA colonization was not associated with vancomycin use past 72 hours (OR, 0.94; 95% CI, 0.8-1.1). A negative MRSA nasal swab on admission had a high negative predictive value for all MRSA infections evaluated (99.6% for pneumonia, 99.6% for bloodstream infection, and 98.1% for skin and soft tissue infection).

Conclusions: Admission surveillance for MRSA nasal colonization is not a major driver of prolonged vancomycin use. A negative admission MRSA nasal screen may be a useful tool for antimicrobial stewardship programs to limit vancomycin use, particularly in noncritically ill patients.

Keywords: Methicillin-resistant Staphylococcus aureus; Surveillance; Vancomycin.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / therapeutic use*
  • Boston
  • Carrier State / diagnosis*
  • Carrier State / microbiology
  • Diagnostic Tests, Routine*
  • Female
  • Hospitals
  • Humans
  • Male
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Middle Aged
  • Retrospective Studies
  • Staphylococcal Infections / diagnosis*
  • Staphylococcal Infections / microbiology
  • Time Factors
  • Vancomycin / therapeutic use*
  • Young Adult

Substances

  • Anti-Bacterial Agents
  • Vancomycin