" Decreasing Inappropriate Treatment of Urine Cultures: A Lab-based and Provider Behavior Approach"

Background:

IDSA guidelines recommend ordering urine cultures based on signs and symptoms that are indicative of infection. Numerous studies have demonstrated urine cultures are sent at high frequency, without appropriate clinical indication, leading to the inappropriate use of antimicrobial therapy. Compounding the issue, many labs have implemented “reflex urine testing.” This strategy provides a high negative predictive value, but produces elevated rates of “positive” culture results, which do not necessarily align with a clinical picture of infection. At our institution, reflex testing was performed via two orders. The first, was an order for “urine screen to culture”, which consisted of a urine dipstick, which triggered a culture if there were nitrites or leukocyte esterase present. The second order was entitled “Adult UTI panel,” which consisted of urine dipstick, urine microscopy and the specimen would be sent for culture, if nitrites or leukocyte esterase or WBC ≥ 5 or if there was presence of any bacteria.

Methods:

 We addressed this dilemma with a two - fold, prospective response: from both the lab and from the provider. The “urine screen to culture” was removed from possible orders and the urine dipstick was removed from the “Adult UTI panel. “ Simultaneously, we recruited our intensive care units to initiate sign and symptom based urine testing, with requirement of checklist completion prior to a urine culture being sent. In addition, standardized approaches to urinary catheter care and how to obtain a urine specimen correctly were disseminated to the nursing staff. Patients for which urine testing was not performed were used as negative controls to assess for negative outcomes.

Results:

Our preliminary results demonstrate a decrease in the number of urine specimens being sent for culture, a decrease in urine specimens sent reflexively for culture and a decrease in contaminated samples, with no negative outcomes.

Conclusion:

Both a decrease of criteria for reflex to culture and systematic reinforcement of sign and symptom based testing lead to decrease in inappropriate testing and false positive culture results. The effect on antimicrobial use as a result of these changes is undergoing evaluation.