Why is asymptomatic bacteriuria overtreated?: A tertiary care institutional survey of resident physicians (BMC Infectious Diseases)

Background: Asymptomatic bacteriuria (ABU) is common and often leads to unnecessary antimicrobial use. Reducing antibiotic overuse for ABU is therefore an important issue for antimicrobial stewardship. We performed this study to investigate the appropriateness of ABU management and to evaluate physicians’ knowledge and practice regarding ABU. Methods: We reviewed all urine cultures of ≥10 5  cfu/mL of bacteria among inpatients in a 900-bed hospital in 2011. Each episode of bacteriuria was classified into ABU or urinary tract infection (UTI). ABU was defined as a positive urine culture (≥10 5  cfu/mL) without symptoms or signs suggesting UTI. In October 2012 a cross-sectional survey of resident physicians was undertaken using an anonymous, self-administered questionnaire. Results: We identified 219 ABU cases among 1167 positive urine cultures, of which 70 (32.0 %) were inappropriately treated. Female gender, old age, pyuria, hematuria, and positive nitrite on urinalysis were associated with inappropriate ABU treatment in a multivariate analysis (P