|Articles|April 14, 2021

Improving Urine Collection Poses Opportunity for Diagnostic Stewardship in Primary Care

Author(s)Killian Meara

More than half of urine cultures were found to be contaminated and 1 in 5 of the patients were prescribed an antibiotic.

Urine cultures exhibit a significant influence on the treatment of suspected urinary tract infections (UTI) and are the most common microbiological tests in outpatient settings.

While results from urine cultures are typically needed for confirmation of a UTI diagnosis, physicians will often prescribe antibiotics before results are received.

This poses a threat to patient care, because although urine cultures are the gold standard for a UTI diagnosis, they can easily become contaminated during the collection process and physicians will often need to make adjustments to treatment once they receive the testing results.

To determine the prevalence of contaminated cultures, along with predictors and antibiotic use associated with contaminated urine cultures, investigators analyzed data from 2 adult safety net primary care clinics.

The study included 1,265 patients and found that of those, 264 had no culture growth, 694 were contaminated, 159 had low counts of growth and 148 had high counts of growth. Additional findings showed that of the 694 with contaminated cultures, 153 were prescribed an antibiotic and of the 264 who showed no culture growth, 36 were prescribed an antibiotic.

This study demonstrates that more than half of urine cultures tend to be contaminated, and that 1 in 5 patients were treated with an antibiotic.

Reducing the contamination of urine cultures will almost certainly provide an improvement on patient care, as more accurate records are relevant to managing any future UTI episodes.

Contagion spoke to Larissa Grigoryan, MD, PhD, assistant professor of Family and Community Medicine at the Baylor College of Medicine, who presented the research at The Society for Healthcare Epidemiology of America Conference 2021, about the study.


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