Patient Care brings primary care clinicians a lot of medical news every day—it’s easy to miss an important study. The Daily Dose provides a concise summary of one of the website's leading stories you may not have seen.
On March 21, 2025, we reported on a study published in Antimicrobial Stewardship & Healthcare Epidemiology that compared the overlap and differences in inappropriate antibiotic use between patients with asymptomatic bacteriuria (ASB) and asymptomatic pyuria and/or nitrituria (ASPN).
The study
Investigators from the University of Washington Center for Stewardship in Medicine analyzed data from 10 critical access hospitals (CAHs) across the US, reviewing cases of 1036 adult patients who underwent urinalysis and urine cultures between September 2022 and May 2023. The primary outcome was inappropriate antibiotic treatment prevalence in asymptomatic ASB and ASPN.
The findings
Of the 824 patients who met inclusion criteria, 347 (42%) showed no signs or symptoms of a UTI. Despite this, 249 of these asymptomatic patients (72%) were treated with antibiotics.
Results also showed that the ASPN criteria captured 40% more cases of unnecessary antibiotic use compared to the traditional definition of ASB, which relies on significant bacterial growth (≥100 000 colony- forming units [CFU]/ml) in the absence of symptoms.
Authors' comments
"Our study suggests that including patients with ASPN would provide a more comprehensive means of quantifying unnecessary antibiotic prescribing and may better inform ASP efforts. Additional studies are needed to identify the prevalence of ASPN in other settings and measure the impact of stewardship program review and intervention."
