1876. Patient- and Hospital-Level Factors and Outcomes Associated with Treatment of Asymptomatic Bacteriuria in Hospitalized Patients: A Multi-Hospital Cohort Study
Session: Poster Abstract Session: Antimicrobial Stewardship: Potpourri
Saturday, October 6, 2018
Room: S Poster Hall
  • IDWeek poster ASB risk factors vFINAL.pdf (300.4 kB)
  • Background: Treatment of asymptomatic bacteriuria (ASB) is a major driver of inappropriate antibiotic use and an important target for antimicrobial stewardship. We identified patient- and hospital-level factors associated with treatment of ASB and its impact on patient outcomes.

    Methods: In this retrospective cohort study, detailed data were abstracted from the medical record of adult non-ICU patients hospitalized with a positive urine culture (Ucx) between 1/2016 and 2/2018 at 46 Michigan hospitals.  Exclusions included pregnancy, urologic surgery or abnormality, immune-compromise, or concomitant infection. ASB was defined as a positive Ucx without signs or symptoms attributable to a urinary tract infection (UTI). The treatment group received ≥1 antibiotic dose. Patient outcomes included mortality, readmissions, Clostridium difficile infection, and emergency room visits. Patient and hospital factors associated with ASB treatment were evaluated using logistic generalized estimating equation models; patient outcomes were inverse probability of treatment weighted.

    Results: Of 2733 included patients with ASB, 82.9% (n=2266) were treated with antibiotics for a median 7 days (IQR 4,9). Ceftriaxone (71.1%) was the most frequent initial therapy; fluoroquinolones (33.2%) were most common at discharge. In the multivariable model, patient variables associated with ASB treatment included: increased age, dementia, positive urinalysis, incontinence, indwelling urinary catheter, and non-ambulatory status [Figure 1]. Hospitals varied [Figure 2], but those that required a documented indication for antibiotics in the order or medical record had lower ASB treatment rates (OR=0.5). There was no difference in patient outcomes for patients treated vs not treated with antibiotics.

    Conclusion:  Antibiotic treatment of ASB, often broad-spectrum, is widespread. Certain patient characteristics (including advanced age, non-ambulatory, dementia, and incontinence) and the misinterpretation of test results (including overemphasis of the urinalysis) drive clinicians to treat ASB. Requiring documentation of antibiotic indication may decrease inappropriate treatment. Future interventions may be more effective by incorporating these drivers of ASB treatment.

    Lindsay Petty, M.D.1, Anna Conlon, PhD2, Valerie Vaughn, MD, MSc3, Daniel Nielsen, MS2, Keith Kaye, MD, MPH4, Anurag Malani, MD, FIDSA5, Rama Thyagarajan, MD6, Danielle Osterholzer, MD7, Gregory Eschenauer, PharmD, BCPS8, Scott Flanders, M.D.4 and Tejal N. Gandhi, MD9, (1)Infectious Diseases, Michigan Medicine, Ann Arbor, MI, (2)University of Michigan Health System, Ann Arbor, MI, (3)Internal Medicine, University of Michigan, Ann Arbor, MI, (4)University of Michigan, Ann Arbor, MI, (5)St. Joseph Mercy Health System, Ypsilanti, MI, (6)Internal Medicine/Infectious Disease, Beaumont Health- Dearborn, Dearborn, MI, (7)Hurley Medical Center, Flint, MI, (8)Michigan Medicine, Ann Arbor, MI, (9)Internal Medicine, Division of Infectious Diseases, Michigan Medicine, Ann Arbor, MI


    L. Petty, None

    A. Conlon, None

    V. Vaughn, None

    D. Nielsen, None

    K. Kaye, None

    A. Malani, None

    R. Thyagarajan, None

    D. Osterholzer, None

    G. Eschenauer, None

    S. Flanders, None

    T. N. Gandhi, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 3rd with the exception of research findings presented at the IDWeek press conferences.