Antimicrobial Stewardship Initiative to Reduce Antibiotic Use for Asymptomatic Bacteriuria (ASB)

Abstract

Background. The use of antibiotics for ASB is inappropriate with the exception of cases involving pregnancy or traumatic urologic procedures. Otherwise, untreated ASB has not been shown to cause harm. Treating ASB is a risk factor in developing symptomatic urinary tract infections (UTI), Clostridium difficile infection and selection of multidrug-resistant pathogens. This study aimed to assess the impact of an antimicrobial stewardship educational intervention directed to reduce inappropriate antibiotic use associated with ASB in a large academic medical center Methods. A controlled quasi-experimental antimicrobial stewardship education and quality improvement study consisted of a historical control group (HCG), October 2015-December 2015, and an interventional education group (IEG), January 2016- March 2016. Study patients were identified from daily urinalysis reports and were included if they were admitted to the hospital, >18 years of age with a reported urinalysis and urine culture. Patients were excluded if they had documented signs/symptoms of a UTI, cultures from a nephrostomy bag, altered mental status, candiduria, neutropenia, were pregnant, underwent a urologic procedure, or received antibiotics for a co-infection. For the IEG, physicians were contacted by an ID pharmacist to discuss proper management of ASB and the need for antimicrobial therapy. To meet a power of 80%, 26 patients in each group were needed. Results. Twenty-six unique patients met inclusion criteria for each group and baseline demographics were similar. Levofloxacin was the most common antibiotic used in the HCG (39%), followed by ceftriaxone and amoxicillin/clavulanate. Duration of antibiotics reduced from an average of 4.3 days in the HCG to 0.38 days in the IEG, p < 0.0001. The initiation of antibiotics decreased from 88% in the HCG to 23% in the IEG, p = 0.001. Majority of inappropriate antibiotic use for ASB were on floors without a rounding pharmacist. An 8-fold decrease in antibiotic cost was observed as a result of active intervention and education, p = 0.01. Conclusion. An interventional approach with a focus on education was found to be effective in reducing the duration and initiation of antibiotics for ASB with significant cost savings. Our study underscores the value of clinical rounding pharmacists who can actively educate on and advocate for appropriate use of antibiotics.