1001. Risk Factors For Treatment of Asymptomatic Bacteruria: Does an Educational Intervention Reduce Unnecessary Treatment?
Session: Poster Abstract Session: Stewardship: Implementing Programs
Friday, October 4, 2013
Room: The Moscone Center: Poster Hall C


Asymptomatic bacteriuria (ABU) does not require treatment in the majority of patients as this does not improve patient outcomes and may be harmful. We aimed to identify risk factors for inappropriate antibiotic use and to evaluate an educational intervention to reduce inappropriate use.


Consecutive patients with positive urine cultures between January 30 and April 30 2012 (baseline) and 2013 (intervention), respectively, were enrolled at two adult tertiary care hospitals. Nursing interviews and chart reviews were conducted to investigate new signs and symptoms of a urinary tract infection. Risk factors for inappropriate antibiotic use for ABU were identified during baseline. In January 2013, an educational intervention was provided to medical residents (monthly) in the clinical teaching unit (CTU) at the intervention site with the CTU at another site serving as the control. The education focused on previously identified risk factors for inappropriate management. A comment on how to manage ABU was added to culture reports for both sites in January 2013.


In 2012, 162/341 (47.5%) positive urine cultures were obtained from asymptomatic patients, and 97 (59.9%) thereof were inappropriately treated with antibiotics. Risk factors identified included female sex (OR 2.0, 95% CI 1.0-4.0), absence of a catheter (OR 2.4, 1.3-4.5), bacteriuria versus candiduria (OR 11.2, 4.0-31.3), pyuria (OR 2.1, 1.1-4.0), and positive nitrites (OR 2.4, 1.2-4.9). On the intervention unit, inappropriate use of antibiotics was reduced from 10/21 (48%; see Figure) in 2012 to 2/23 (9%; OR 0.10, 0.02-0.56) in 2013. Comparison to the control CTU for the year 2013 (14/27, 52%) also showed a significant reduction in inappropriate antibiotic use (OR 0.09, 0.02-0.45). No statistical difference was found in the control site between 2012 and 2013 (OR 0.54, 0.14-2.0).


Educational sessions geared towards medical residents and staff physicians with a focus on previously identified factors resulting in inappropriate management of ABU were highly effective in reducing unnecessary use of antibiotics. Comments on management of ABU on culture results did not reduce inappropriate antibiotic use in the absence of an educational intervention.

Figure 1a) Intervention group

Figure 1b) Control group

Annie Brooks, PharmD1, Neal Irfan, PharmD1, Siraj Mithoowani, BSc2, Daniel J Lee, BHSc2, Alexander Carducci, BSc3, Steve Celetti, MS3, Allan Cheng, BSc3 and Dominik Mertz, MD, MSc4,5,6, (1)Hamilton Health Sciences, Hamilton, ON, Canada, (2)Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada, (3)Faculty of Pharmacy, University of Waterloo, Waterloo, ON, Canada, (4)Infection Prevention and Control, Hamilton Health Sciences, Hamilton, ON, Canada, (5)Department of Medicine, McMaster University, Hamilton, ON, Canada, (6)Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada


A. Brooks, None

N. Irfan, None

S. Mithoowani, None

D. J. Lee, None

A. Carducci, None

S. Celetti, None

A. Cheng, None

D. Mertz, None

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