Diagnostic Stewardship to Improve the Diagnosis of Urinary Tract Infections

Abstract

Urinary tract infections (UTIs) are common infections, however diagnosis remains challenging. Asymptomatic bacteriuria (positive urine cultures in the absence of true infection) represent a major driver of inappropriate diagnosis and unnecessary antimicrobials. Curbing the impact of inappropriate diagnosis of UTIs often falls upon antimicrobial stewardship (AMS) programs, however AMS interventions occur after diagnosis. In contrast, diagnostic stewardship is an innovative approach that intervenes at across the diagnostic pathway (urine culture ordering, processing, and reporting), upstream of traditional AMS activities, and has the potential to significantly impact diagnosis and management decisions. Best practices and optimal implementation of diagnostic stewardship, however, have yet to be fully described. Specific Aim 1 evaluated the feasibility and impact of conditional urine testing. This study compared three Veterans Affairs (VA) hospitals that had implemented this diagnostic stewardship intervention compared to three control sites. Conditional urine testing, particularly with more restrictive requirements, was associated with significantly fewer urine cultures performed. Importantly, there were no serious unintended consequences, such as secondary bacteremia, related to missed diagnosis of UTI at the population level. Specific Aim 2 sought to comprehensively review available diagnostic stewardship interventions and create expert guidance for best practices to improve diagnosis of UTI. Traditionally, guidelines for diagnosis and management of infections do not address diagnostic stewardship interventions, particularly those at the institutional or health system level. This Aim distilled available literature into best practices for urine culture stewardship through expert guidance and will serve as a guide for clinicians in the future. Specific Aim 3 applied implementation science and user-centered design principles to develop urine culture diagnostic stewardship interventions for three geographically diverse VA medical centers. This included interventions focused on urine culture ordering, processing, and reporting. Prototype intervention tools were refined using qualitative methods to facilitate local implementation at each participating site and ensure long-term intervention success. Patient-centered diagnostic stewardship can lead to improved patient outcomes and less antimicrobial misuse. The results of these three aims will be used to demonstrate the impact of urine culture diagnostic stewardship best practices on these outcomes and ultimately lead to an implementation toolkit to be used nationwide.