Antibiotic treatment for asymptomatic bacteriuria (ASB) is prevalent but often contrary to published guidelines.

To evaluate risk factors for treatment of ASB.

Retrospective observational study.

A tertiary academic hospital, county hospital, and community hospital.

Hospitalized adults with bacteriuria.

Patients without documented symptoms of urinary tract infection per Infectious Diseases Society of America (IDSA) criteria were classified as ASB. We examined ASB treatment risk factors as well as broad-spectrum antibiotic usage and quantified diagnostic concordance between IDSA and National Healthcare Safety Network criteria.

Among 300 patients with bacteriuria, ASB was present in 71% by IDSA criteria. By National Healthcare Safety Network criteria, 71% of patients had ASB; within-patient diagnostic concordance with IDSA was moderate (kappa, 0.52). After excluding those given antibiotics for nonurinary indications, antibiotics were given to 38% (62/164) with ASB. Factors significantly associated with ASB treatment were elevated urine white cell count (65 vs 24 white blood cells per high-powered field, P<.01), hospital identity (hospital C vs A, odds ratio, 0.34 [95% CI, 0.14–0.80], P =.01), presence of leukocyte esterase (5.48 [2.35–12.79], P<.01), presence of nitrites (2.45 [1.11–5.41], P=.03), and Escherichia coli on culture (2.4 [1.2–4.7], P=.01). Of patients treated for ASB, broad-spectrum antibiotics were used in 84%.

ASB treatment was prevalent across settings and contributed to broad-spectrum antibiotic use. Associating abnormal urinalysis results with the need for antibiotic treatment regardless of symptoms may drive unnecessary antibiotic use.

Infect. Control Hosp. Epidemiol. 2016;37(3):319–326