Prescriber Behavior in Clostridioides difficile Testing: A 3-Hospital Diagnostic Stewardship Intervention

Implementation of multifaceted diagnostic stewardship for Clostridioides difficile infection during the COVID-19 pandemic at a small Japanese hospital

Objective

Clostridioides difficile infection (CDI) is a common, healthcare-associated infection. However, in Japan, testing for CDI is infrequent, suggesting that its incidence may be underestimated. This study aimed to examine the implementation of a multifaceted, diagnostic stewardship (DS) for CDI in a small Japanese hospital during the coronavirus 2019 pandemic.

Design

Before-after study.

Setting

A small Japanese community hospital.

Participants

Healthcare workers including physicians, nurses, and pharmacists.

Interventions

A multifaceted intervention including (1) the addition of CD testing criteria to the hospital guidelines; (2) provision of a tutorial on CD testing to physicians, nurses, and pharmacists; (3) assessment by clinical pharmacists and nurses of the need for CD testing in patients with nosocomial diarrhea and issuance of recommendations for CD testing to physicians; (4) reporting of data on the CD testing rate and CDI incidence in the study center.

Results

The CD testing rate increased before the pandemic (+0.16/10,000 patient-days (PD); P = .28), decreased significantly during the pandemic (-0.79/10,000 PD; P = .02), and then increased significantly immediately after the implementation of the intervention (+29.6/10,000 PD; P < .01). Similarly, the CDI incidence increased significantly before the pandemic (+0.26/10,000 PD; P = .02) and decreased significantly during the pandemic (-0.49/10,000 PD; P = .01). Implementation of the intervention resulted in an immediate and significant increase in the CDI incidence (+6.2/10,000 PD; P < .01).

Conclusion

Multifaceted DS involving multidisciplinary specialists was effective in improving CD testing, suggesting that appropriate testing can contribute to diagnosing CDI accurately.

Diagnostic stewardship in infectious diseases: a scoping review

Introduction. The term 'diagnostic stewardship' is relatively new, with a recent surge in its use within the literature. Despite its increasing popularity, a precise definition remains elusive. Various attempts have been made to define it, with some viewing it as an integral part of antimicrobial stewardship. The World Health Organization offers a broad definition, emphasizing the importance of timely, accurate diagnostics. However, inconsistencies in the use of this term still persist, necessitating further clarification.Gap Statement. There are currently inconsistencies in the definition of diagnostic stewardship used within the academic literature.Aim. This scoping review aims to categorize the use of diagnostic stewardship approaches and define this approach by identifying common characteristics and factors of its use within the literature.Methodology. This scoping review undertook a multi-database search from date of inception until October 2022. Any observational or experimental study where the authors define the intervention to be diagnostic stewardship from any clinical area was included. Screening of all papers was undertaken by a single reviewer with 10% verification by a second reviewer. Data extraction was undertaken by a single reviewer using a pre-piloted form. Given the wide variation in study design and intervention outcomes, a narrative synthesis approach was applied. Studies were clustered around common diagnostic stewardship interventions where appropriate.Results. After duplicate removal, a total of 1310 citations were identified, of which, after full-paper screening, 105 studies were included in this scoping review. The classification of an intervention as taking a diagnostic stewardship approach is a relatively recent development, with the first publication in this field dating back to 2017. The majority of research in this area has been conducted within the USA, with very few studies undertaken outside this region. Visual inspection of the citation map reveals that the current evidence base is interconnected, with frequent references to each other's work. The interventions commonly adopt a restrictive approach, utilizing hard and soft stops within the pre-analytical phase to restrict access to testing. Upon closer examination of the outcomes, it becomes evident that there is a predominant focus on reducing the number of tests rather than enhancing the current test protocol. This is further reflected in the limited number of studies that report on test performance (including protocol improvements, specificity and sensitivity).Conclusion. Diagnostic stewardship seems to have deviated from its intended course, morphing into a rather rudimentary instrument wielded not to enhance but to constrict the scope of testing. Despite the World Health Organization's advocacy for an ideology that promotes a more comprehensive approach to quality improvement, it may be more appropriate to consider alternative regional narratives when categorizing these types of quality improvement interventions.

Diagnostic stewardship to improve patient outcomes and healthcare-associated infection (HAI) metrics

Diagnostic stewardship seeks to improve ordering, collection, performance, and reporting of tests. Test results play an important role in reportable HAIs. The inclusion of HAIs in public reporting and pay for performance programs has highlighted the value of diagnostic stewardship as part of infection prevention initiatives. Inappropriate testing should be discouraged, and approaches that seek to alter testing solely to impact a reportable metric should be avoided. HAI definitions should be further adapted to new testing technologies, with focus on actionable and clinically relevant test results that will improve patient care.

A decade of clinical microbiology: top 10 advances in 10 years: what every infection preventionist and antimicrobial steward should know

The past 10 years have brought paradigm-shifting changes to clinical microbiology. This paper explores the top 10 transformative innovations across the diagnostic spectrum, including not only state of the art technologies but also preanalytic and post-analytic advances. Clinical decision support tools have reshaped testing practices, curbing unnecessary tests. Innovations like broad-range polymerase chain reaction and metagenomic sequencing, whole genome sequencing, multiplex molecular panels, rapid phenotypic susceptibility testing, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry have all expanded our diagnostic armamentarium. Rapid home-based testing has made diagnostic testing more accessible than ever. Enhancements to clinician-laboratory interfaces allow for automated stewardship interventions and education. Laboratory restructuring and consolidation efforts are reshaping the field of microbiology, presenting both opportunities and challenges for the future of clinical microbiology laboratories. Here, we review key innovations of the last decade.

Effective Approaches to Diagnostic Stewardship of Syndromic Molecular Panels

BACKGROUND

Syndromic molecular panels for the diagnosis of gastroenteritis, meningitis/encephalitis, and pneumonia are becoming routinely used for patient care throughout the world.

CONTENT

These rapid, sample-to-answer assays have great potential to improve patient care, infection control, and antimicrobial stewardship. However, diagnostic stewardship is essential for their optimal use and accuracy, and interventions can be applied at all phases of the diagnostic process.

SUMMARY

The aim of this review article is to describe effective approaches to diagnostic stewardship for syndromic molecular panels to ensure appropriate test utilization and quality assured results.

A diagnostic stewardship approach to prevent unnecessary testing of an enteric bacterial molecular panel

IMPORTANCE

Testing for enteric bacterial pathogens in patients hospitalized for more than 3 days is almost always inappropriate. Our study validates the utility of the 3-day rule and the use of clinical decision support tools to decrease unnecessary testing of enteropathogenic bacteria other than C. difficile. Overriding the restriction was very low yield. Our study highlights the importance of diagnostic stewardship and further refines the criteria for allowing providers to override the restriction while monitoring the impact of the interventions.

Behavioral Strategies in Diagnostic Stewardship

Diagnostic stewardship refers to the responsible and judicious use of diagnostic tests to reduce low value care and improve patient outcomes. This article provides an overview of behavioral strategies, their relevance to diagnostic stewardship and highlights behavioral determinants that drive diagnostic testing behavior, drawing on theoretic frameworks. Additionally, we provide concrete examples of evidence-based behavioral strategies for promoting appropriate diagnostic testing while acknowledging associated challenges. Finally, we highlight the significance of evaluating these strategies and provide an overview of evaluation frameworks and methods.

Clostridioides difficile dynamic electronic order panel, an effective automated intervention to reduce inappropriate inpatient ordering

BACKGROUND

Ordering Clostridioides difficile diagnostics without appropriate clinical indications can result in inappropriate antibiotic prescribing and misdiagnosis of hospital onset C. difficile infection. Manual processes such as provider review of order appropriateness may detract from other infection control or antibiotic stewardship activities.

METHODS

We developed an evidence-based clinical algorithm that defined appropriateness criteria for testing for C. difficile infection. We then implemented an electronic medical record-based order-entry tool that utilized discrete branches within the clinical algorithm including history of prior C. difficile test results, laxative or stool-softener administration, and documentation of unformed bowel movements. Testing guidance was then dynamically displayed with supporting patient data. We compared the rate of completed C. difficile tests after implementation of this intervention at 5 hospitals to a historic baseline in which a best-practice advisory was used.

RESULTS

Using mixed-effects Poisson regression, we found that the intervention was associated with a reduction in the incidence rate of both C. difficile ordering (incidence rate ratio [IRR], 0.74; 95% confidence interval [CI], 0.63-0.88; P = .001) and C. difficile-positive tests (IRR, 0.83; 95% CI, 0.76-0.91; P < .001). On segmented regression analysis, we identified a sustained reduction in orders over time among academic hospitals and a new reduction in orders over time among community hospitals.

CONCLUSIONS

An evidence-based dynamic order panel, integrated within the electronic medical record, was associated with a reduction in both C. difficile ordering and positive tests in comparison to a best practice advisory, although the impact varied between academic and community facilities.

Leveraging diagnostic stewardship within antimicrobial stewardship programmes

Novel diagnostic stewardship in infectious disease consists of interventions that modify ordering, processing, and reporting of diagnostic tests to provide the right test for the right patient, prompting the right action. The interventions work upstream and synergistically with traditional antimicrobial stewardship efforts. As diagnostic stewardship continues to gain public attention, it is critical that antimicrobial stewardship programmes not only learn how to effectively leverage diagnostic testing to improve antimicrobial use but also ensure that they are stakeholders and leaders in developing new diagnostic stewardship interventions within their institutions. This review will discuss the need for diagnostic and antimicrobial stewardship, the interplay of diagnostic and antimicrobial stewardship, evidence of benefit to antimicrobial stewardship programmes, and considerations for successfully engaging in diagnostic stewardship interventions. This article is part of the Antibiotic stewardship Special Issue: https://www.drugsincontext.com/special_issues/antimicrobial-stewardship-a-focus-on-the-need-for-moderation.

Role of diagnostic stewardship in reducing healthcare-facility–onset Clostridioides difficile infections

We describe the implementation of an electronic medical record “hard stop” to decrease inappropriate Clostridioides difficile testing across a 5-hospital health system, effectively reducing the rates of healthcare-facility–onset C. difficile infection. This novel approach included expert consultation with medical director of infection prevention and control for test-order override.

SEE the DIFFerence: Reducing unnecessary C. difficile orders through clinical decision support in a large, urban safety-net system

BACKGROUND

Clostridioides difficile (C. difficile) is a hospital-acquired infection. Overtesting for C. difficile leads to false positive results due to a high rate of asymptomatic colonization, resulting in unnecessary and harmful treatment for patients.

METHODS

This was a quality improvement initiative to decrease the rate of inappropriate C. difficile testing across 11 hospitals in an urban, safety-net setting. Three best practice advisories were created, alerting providers of recent laxative administration within 48 hours, a recent positive test within 14 days, and a recent negative test within 7 days. The outcome measures were the number of C. difficile tests per 1,000 patient days, as well as the rate of hospital onset C. difficile infection was compared pre- and post-intervention. The process measures included the rate of removal of the C. difficile test from the best practice advisory, as well as the subsequent 24-hour re-order rate.

RESULTS

The number of C. difficile tests decreased by 27.3% from 1.1 per 1,000 patient days preintervention (May 25, 2020-May 24, 2021) to 0.8 per 1,000 patient days postintervention, (May 25, 2021-March 25, 2022), P < .001. When stratified by hospital, changes in testing ranged from an increase of 12.5% to a decrease of 60%. Analysis among provider type showed higher behavior change among attendings than compared to trainees or advanced practice providers. There was a 12.1%, nonsignificant decrease in C. difficile rates from preintervention, 0.33 per 1,000 patient days compared to postintervention, 0.29 per 1,000 patient days, P=.32.

CONCLUSIONS

Using only an electronic health record intervention, we successfully decreased C. difficile orders after 72 hours of admission in a large, safety-net system. Variation existed among hospitals and by provider type.

Clinical Decision Support Systems to Reduce Unnecessary Clostridoides difficile Testing Across Multiple Hospitals

BACKGROUND

Inappropriate C. difficile testing has adverse consequences for the patient, hospital, and public health. Computerized Clinical Decision Supports (CCDS) in the Electronic Health Record (EHR) may reduce C. difficile test ordering; however, effectiveness of different approaches, ease of use, and best fit into the healthcare providers' (HCP) workflow, are not well understood.

METHODS

Nine academic and 6 community U.S. hospitals participated in this 2-year cohort study. CCDS (hard- or soft-stop) triggered when duplicate C. difficile test order attempted, or if laxatives were recently received. The primary outcome was the difference in testing rates pre- and post-CCDS interventions, using incident rate ratios (IRR) and mixed effect Poisson regression models. We performed qualitative evaluation (contextual inquiry, interviews, focus groups) based on a human factors model. We identified themes using a codebook with primary- and sub-nodes.

RESULTS

In 9 hospitals implementing hard-stop CCDS and 4 hospitals implementing soft-stop CCDS, C. difficile testing IRR reduction was 33% (95% CI, 30-36%), and 23% (95% CI 21-25%), respectively. Two hospitals implemented a non-EMR based human intervention with IRR reduction of 21% (95% CI 15-28%). HCPs reported generally favorable experiences, and highlighted time efficiencies such as inclusion of the patients most recent laxative administration on the CCDS. Organizational factors including hierarchical cultures, and communication between HCPs caring for the same patient, impact CCDS acceptance and integration.

CONCLUSIONS

CCDS reduced unnecessary C. difficile testing and were perceived positively by HCPs when integrated into their workflow, and when displayed relevant patient specific information needed for decision-making.

Diagnostic Stewardship in Clinical Microbiology, Essential Partner to Antimicrobial Stewardship

Background

Diagnostic stewardship is an important partner to antimicrobial stewardship.

Content

Diagnostic stewardship focuses on ensuring correct diagnosis of infectious diseases while antimicrobial stewardship aims to optimize antimicrobial treatment. Both aim to improve patient outcomes. Diagnostic stewardship involves interventions that reduce testing in patients with low pretest probability, optimize a test’s likelihood ratio, and seek to warn providers when suboptimal test results might have been reported.

Conclusion

Diagnostic stewardship interventions have been described primarily in the areas of urinary tract infection, Clostridioides difficile infection, and bloodstream infection diagnosis. However, emerging areas include pneumonia and wound infections in addition to optimization of multiplexed panel-based testing.

Impact of Statewide Prevention and Reduction of Clostridioides difficile (SPARC), a Maryland public health-academic collaborative: an evaluation of a quality improvement intervention

To evaluate changes in Clostridioides difficile incidence rates for Maryland hospitals that participated in the Statewide Prevention and Reduction of C. difficile (SPARC) collaborative. Pre-post, difference-in-difference analysis of non-randomised intervention using four quarters of preintervention and six quarters of postintervention National Healthcare Safety Network data for SPARC hospitals (April 2017 to March 2020) and 10 quarters for control hospitals (October 2017 to March 2020). Mixed-effects negative binomial models were used to assess changes over time. Process evaluation using hospital intervention implementation plans, assessments and interviews with staff at eight SPARC hospitals. Maryland, USA. All Maryland acute care hospitals; 12 intervention and 36 control hospitals. Participation in SPARC, a public health-academic collaborative made available to Maryland hospitals, with staggered enrolment between June 2018 and August 2019. Hospitals with higher C. difficile rates were recruited via email and phone. SPARC included assessments, feedback reports and ongoing technical assistance. Primary outcomes were C. difficile incidence rate measured as the quarterly number of C. difficile infections per 10 000 patient-days (outcome measure) and SPARC intervention hospitals' experiences participating in the collaborative (process measures). SPARC invited 13 hospitals to participate in the intervention, with 92% (n=12) participating. The 36 hospitals that did not participate served as control hospitals. SPARC hospitals were associated with 45% greater C. difficile reduction as compared with control hospitals (incidence rate ratio=0.55, 95% CI 0.35 to 0.88, p=0.012). Key SPARC activities, including access to trusted external experts, technical assistance, multidisciplinary collaboration, an accountability structure, peer-to-peer learning opportunities and educational resources, were associated with hospitals reporting positive experiences with SPARC. SPARC intervention hospitals experienced 45% greater reduction in C. difficile rates than control hospitals. A public health-academic collaborative might help reduce C. difficile and other hospital-acquired infections in individual hospitals and at state or regional levels.

The future of Clostridioides difficile diagnostics

PURPOSE OF REVIEW

Although the epidemiology of Clostridioides difficile has changed, this organism continues to cause significant morbidity and mortality. This review addresses current and future approaches to the diagnosis of C. difficile disease.

RECENT FINDINGS

Over the last several years, large prospective studies have confirmed that there is no single optimal test for the diagnosis of C. difficile disease. The pendulum has swung from a focus on rapid molecular diagnosis during the years of the ribotype 027 epidemic, to a call for use of algorithmic approaches that include a test for toxin detection. In addition, diagnostic stewardship has been shown to improve test utilization, especially with molecular methods. Advances in testing include development of ultrasensitive toxin tests and an expansion of biomarkers that may be more C. difficile specific. Microbiome research may be leveraged to inform novel diagnostic approaches based on measurements of volatile and nonvolatile organic compounds in stool.

SUMMARY

As rates of C. difficile infection decline, emphasis is now on improving test utilization and a quest for improved diagnostic approaches. These approaches may involve implementation of technologies that improve toxin testing, predict patients likely to have disease and/or a severe outcome, and harnessing research on changes in the microbiome to advance metabolomics.

Use of diagnostic and antimicrobial stewardship practices to improve Clostridioides difficile testing among SHEA Research Network hospitals

We surveyed acute-care hospitals on strategies to reduce inappropriate C. difficile testing and treatment of colonized patients. Decision support during C. difficile test ordering was common, but "hard stops" to prevent placement of inappropriate orders and active intervention of antimicrobial stewardship programs on positive C. difficile test reports were infrequent.

Advancing Diagnostic Stewardship for Healthcare Associated Infections, Antibiotic Resistance, and Sepsis

Diagnostic stewardship means ordering the right tests, for the right patient at the right time to inform optimal clinical care. Diagnostic stewardship is an integral part of antibiotic stewardship efforts to optimize antibiotic use and improve patient outcomes, including reductions in antibiotic resistance, and treatment of sepsis. CDC's Division of Healthcare Quality Promotion (DHQP) hosted a meeting on improving patient safety through diagnostic stewardship with a focus on the use of the laboratory. The meeting identified emerging issues in the field of diagnostic stewardship, raised awareness of these issues among stakeholders, and discussed strategies and interventions to address the issues-all with an emphasis on improved outcomes and patient safety. This white paper summarizes the key takeaways of the meeting including needs for diagnostic stewardship implementation, promising future avenues for diagnostic stewardship implementation, and areas of needed research.

In pursuit of the holy grail: Improving C. difficile testing appropriateness with iterative electronic health record clinical decision support and targeted test restriction

OBJECTIVE

To determine the impact of electronic health record (EHR)-based interventions and test restriction on Clostridioides difficile tests (CDTs) and hospital-onset C. difficile infection (HO-CDI).

DESIGN

Quasi-experimental study in 3 hospitals.

SETTING

957-bed academic (hospital A), 354-bed (hospital B), and 175-bed (hospital C) academic-affiliated community hospitals.

INTERVENTIONS

Three EHR-based interventions were sequentially implemented: (1) alert when ordering a CDT if laxatives administered within 24 hours (January 2018); (2) cancellation of CDT orders after 24 hours (October 2018); (3) contextual rule-driven order questions requiring justification when laxative administered or lack of EHR documentation of diarrhea (July 2019). In February 2019, hospital C implemented a gatekeeper intervention requiring approval for all CDTs after hospital day 3. The impact of the interventions on C. difficile testing and HO-CDI rates was estimated using an interrupted time-series analysis.

RESULTS

C. difficile testing was already declining in the preintervention period (annual change in incidence rate [IR], 0.79; 95% CI, 0.72-0.87) and did not decrease further with the EHR interventions. The laxative alert was temporally associated with a trend reduction in HO-CDI (annual change in IR from baseline, 0.85; 95% CI, 0.75-0.96) at hospitals A and B. The gatekeeper intervention at hospital C was associated with level (IRR, 0.50; 95% CI, 0.42-0.60) and trend reductions in C. difficile testing (annual change in IR, 0.91; 95% CI, 0.85-0.98) and level (IRR 0.42; 95% CI, 0.22-0.81) and trend reductions in HO-CDI (annual change in IR, 0.68; 95% CI, 0.50-0.92) relative to the baseline period.

CONCLUSIONS

Test restriction was more effective than EHR-based clinical decision support to reduce C. difficile testing in our 3-hospital system.

Thinking Beyond the "Core" Antibiotic Stewardship Interventions: Shifting the Onus for Appropriate Antibiotic Use from Stewardship Teams to Prescribing Clinicians

United States guidance for hospital antibiotic stewardship has emphasized prospective audit and feedback and prior authorization of select antibiotics as core interventions. These remain the most common interventions implemented by stewardship programs. Although these approaches have been shown to reduce unnecessary antibiotic use, they incorrectly put the onus for appropriate antibiotic use on the stewardship team rather than the prescribing clinician. We propose that a primary focus of stewardship programs should be implementation of broader interventions that engage frontline clinicians and equip them with tools to integrate antibiotic stewardship into their own daily practice, thus reducing the need for day-to-day stewardship team oversite. We discuss a framework of broader interventions and policies that will facilitate this paradigm shift.

The Impact of Clinical Decision Support Alerts on Clostridioides difficile Testing: A Systematic Review

BACKGROUND

Several studies have investigated the utility of electronic decision support alerts in diagnostic stewardship for Clostridioides difficile infection (CDI). However, it is unclear if alerts are effective in reducing inappropriate CDI testing and/or CDI rates. The aim of this systematic review was to determine if alerts related to CDI diagnostic stewardship are effective at reducing inappropriate CDI testing volume and CDI rates among hospitalized adult patients.

METHODS

We searched Ovid Medline and 5 other databases for original studies evaluating the association between alerts for CDI diagnosis and CDI testing volume and/or CDI rate. Two investigators independently extracted data on study characteristics, study design, alert triggers, cointerventions, and study outcomes.

RESULTS

Eleven studies met criteria for inclusion. Studies varied significantly in alert triggers and in study outcomes. Six of 11 studies demonstrated a statistically significant decrease in CDI testing volume, 6 of 6 studies evaluating appropriateness of CDI testing found a significant reduction in the proportion of inappropriate testing, and 4 of 7 studies measuring CDI rate demonstrated a significant decrease in the CDI rate in the postintervention vs preintervention period. The magnitude of the increase in appropriate CDI testing varied, with some studies reporting an increase with minimal clinical significance.

CONCLUSIONS

The use of electronic alerts for diagnostic stewardship for C. difficile was associated with reductions in CDI testing, the proportion of inappropriate CDI testing, and rates of CDI in most studies. However, broader concerns related to alerts remain understudied, including unintended adverse consequences and alert fatigue.

Advances and required improvements in methods to diagnosing Clostridioides difficile infections in the healthcare setting

INTRODUCTION

Clostrididioides difficile is associated with adverse clinical outcomes and increased morbidity, mortality, length of hospital stay, and health-care costs.Areas Covered: We searched relevant papers in PubMed for the last 10 years. In major papers, we scanned the bibliographies to ensure that important articles were included. This review addresses the evolving epidemiology of Clostridioides difficile infection (CDI) and discusses novel methods/approaches for improving the diagnosis of this important disease.

EXPERT OPINION

No single diagnostic test to date has demonstrated optimum sensitivity and specificity for detection of CDI. Many institutions have developed multi-step algorithms consistent with guidelines established by various professional societies. Some institutions have successfully tried to improve the pretest probability of molecular assays by implementing appropriate sample rejection criteria and establishing best practice alerts at the time of electronic order entry. Others have established PCR cycle threshold cutoffs to attempt to differentiate symptomatic patients from asymptomatic carriers or to make predictions about severity of disease with variable success. As research advances our understanding of C. difficile pathogenesis and pathophysiology, more information on CDI specific biomarkers is emerging. Finally, assessments of the microbiome and metabolome may expand the diagnostic armamentarium with advances in mass spectrometry and sequencing technologies.

Impact of a division-wide bundle on hospital-acquired Clostridioides difficile cases, antibiotic days of therapy, testing appropriateness, and associated financial costs

Introduction:

Updated international guidelines recommend the use of a two-step algorithm (glutamate dehydrogenase [GDH] or nucleic-acid amplification test [NAAT] plus toxin) rather than NAAT alone for the diagnosis of Clostridioides difficile (formerly Clostridium difficile) infections. The goal of our project was to evaluate the impact of a new bundle on the rate of hospital-acquired C. difficile infections (CDIs), hospital-acquired CDI standardized infection ratio (SIR), antibiotic days of therapy (DOT), and financial cost.

Materials and Methods:

The new bundle was implemented in April 2018. This bundle was implemented across five hospitals in Catholic Health Initiatives (CHI) Texas Division. The bundle included a switch from NAAT to a two-step process (GDH and toxin). We placed the new test in an order panel which included enteric isolation and required indications for C. difficile testing. We used quarterly data pre- and post-intervention to calculate SIR and DOT.

Results:

In the pre-intervention period, 15.5% of the total 3513 C. difficile NAAT was positive. In the post-intervention period, 5.7% of a total of 2845 GDH and toxin assays was positive for both GDH and toxin (P < 0.0001). SIR, which adjusts for denominator and change in testing methodology, also dropped from 1.02 to 0.43. The estimated cost associated with positive C. difficile cases dropped from 1,932,150 USD to 1,113,800 USD with an estimated yearly cost saving of 794,150 USD. Compliance with enteric isolation improved from 73.1% to 92.5% (P = 0.008).

Conclusion:

The new testing bundle led to a marked reduction in hospital-acquired CDI and unnecessary treatment, reduction in C. difficile testing, an increase in compliance with enteric isolation, and significant cost savings.

Interventions to optimize antimicrobial stewardship

Developing and improving an antimicrobial stewardship program successfully requires evaluation of numerous factors. As technology progresses and our understanding of antimicrobial resistance grows, careful consideration should be taken to ensure that a program meets the needs of the institution and is achievable given the available resources. In this review, we explore fundamental initiatives and strategies for both new and established antimicrobial stewardship programs, including the specific areas to target and key elements required for sustainable implementation.

Impact of a Clostridioides Difficile Testing Computerized Clinical Decision Support Tool on an Adult Stem Cell Transplantation and Hematologic Malignancies Unit

Clostridioides difficile infection rates are higher in hospitalized hematopoietic stem cell transplantation (HSCT) recipients and patients with hematologic malignancy (HM) compared with the general population. This is related both to extensive exposure to antibiotics as well as to frequent and often prolonged hospitalization. In this population, with numerous potential causes of diarrhea, a subset of C difficile detected is presumed to represent colonization rather than clinical infection. The use of decision support tools to guide ordering in hospitalized patients has been reported to decrease both C difficile testing and detection rates. Following implementation of a computerized decision support tool on our HSCT/HM unit, we observed a >2-fold decrease in C difficile testing volume and National Healthcare Safety Network-defined laboratory identifications of C difficile. Furthermore, the rate of oral vancomycin use, as well as the incidence of vancomycin-resistant enterococci colonization and bloodstream infection, decreased in the postintervention period.

Improving Appropriate Diagnosis of Clostridioides difficile Infection Through an Enteric Pathogen Order Set With Computerized Clinical Decision Support: An Interrupted Time Series Analysis

Background

Inappropriate testing for Clostridioides difficile leads to overdiagnosis of C difficile infection (CDI). We determined the effect of a computerized clinical decision support (CCDS) order set on C difficile polymerase chain reaction (PCR) test utilization and clinical outcomes.

Methods

This study is an interrupted time series analysis comparing C difficile PCR test utilization, hospital-onset CDI (HO-CDI) rates, and clinical outcomes before and after implementation of a CCDS order set at 2 academic medical centers: University of Washington Medical Center (UWMC) and Harborview Medical Center (HMC).

Results

Compared with the 20-month preintervention period, during the 12-month postimplementation of the CCDS order set, there was an immediate and sustained reduction in C difficile PCR test utilization rates at both hospitals (HMC, -28.2% [95% confidence interval {CI}, -43.0% to -9.4%], P = .005; UWMC, -27.4%, [95% CI, -37.5% to -15.6%], P < .001). There was a significant reduction in rates of C difficile tests ordered in the setting of laxatives (HMC, -60.8% [95% CI, -74.3% to -40.1%], P < .001; UWMC, -37.3%, [95% CI, -58.2% to -5.9%], P = .02). The intervention was associated with an increase in the C difficile test positivity rate at HMC (P = .01). There were no significant differences in HO-CDI rates or in the proportion of patients with HO-CDI who developed severe CDI or CDI-associated complications including intensive care unit transfer, extended length of stay, 30-day mortality, and toxic megacolon.

Conclusions

Computerized clinical decision support tools can improve C difficile diagnostic test stewardship without causing harm. Additional studies are needed to identify key elements of CCDS tools to further optimize C difficile testing and assess their effect on adverse clinical outcomes.

The Effect of Clostridioides difficile Diagnostic Stewardship Interventions on the Diagnosis of Hospital-Onset Clostridioides difficile Infections

BACKGROUND

Public reporting of Clostridioides difficile infection (CDI) using laboratory-identified events has led some institutions to revert from molecular-based tests to less sensitive testing modalities. At one academic medical center, researchers chose to use nucleic acid amplification test alone in CDI diagnosis with institutional protocols aimed at diagnostic stewardship.

METHODS

A single-center, quasi-experimental study was conducted to introduce and analyze the effects of various diagnostic stewardship interventions. In April 2017 an order report was created to inform providers of patients' recent bowel movements, laxative use, and prior Clostridioides difficile (CD) testing (Intervention 1). In November 2017 nursing staff were empowered to not send nondiarrheal stools for testing (Intervention 2). In February 2019, an interruptive alert was implemented to prevent testing that was not indicated (Intervention 3). CD testing rates and healthcare facility-onset CDI (HO-CDI) rates were compared before and after the interventions using one-way analysis of variance (ANOVA).

RESULTS

At baseline, testing for CD after 3 days of admission was performed at mean ± standard deviation of 15.9 ± 1.7 tests/1,000 patient-days. After Intervention 1, it decreased to 12.1 ± 1.1 tests. This further decreased to 10.6 ± 0.8 after Intervention 2 and to 8.1 ± 0.1 after Intervention 3 (p < 0.001). HO-CDI cases per 10,000 patient-days declined from 12.7 ± 1.4 cases at baseline to 10.7 ± 1.2 after Intervention 1, to 8.7 ± 2.4 after Intervention 2, and to 5.8 ± 0.2 after Intervention 3 (p = 0.03).

CONCLUSION

A multidisciplinary approach optimizing electronic health record support tools and leveraging nursing education can reduce both testing and HO-CDI rates while using the most sensitive testing modality.

Modest Clostridiodes difficile infection prediction using machine learning models in a tertiary care hospital

Previous studies have shown promising results of machine learning (ML) models for predicting health outcomes. We develop and test ML models for predicting Clostridioides difficile infection (CDI) in hospitalized patients. This is a retrospective cohort study conducted during 2015-2017. All inpatients tested for C. difficile were included. CDI was defined as having a positive glutamate dehydrogenase and toxin results. We restricted analyses to the first record of C. difficile testing per patient. Of 3514 patients tested, 136 (4%) had CDI. Age and antibiotic use within 90 days before C. difficile testing were associated with CDI (P < 0.01). We tested 10 ML methods with and without resampling. Logistic regression, random forest and naïve Bayes models yielded the highest AUC ROC performance: 0.6. Predicting CDI was difficult in our cohort of patients tested for CDI. Multiple ML models yielded only modest results in a real-world population of hospitalized patients tested for CDI.

Incorporating preauthorization into antimicrobial stewardship pharmacist workflow reduces Clostridioides difficile and gastrointestinal panel testing

OBJECTIVE

To evaluate whether incorporating mandatory prior authorization for Clostridioides difficile testing into antimicrobial stewardship pharmacist workflow could reduce testing in patients with alternative etiologies for diarrhea.

DESIGN

Single center, quasi-experimental before-and-after study.

SETTING

Tertiary-care, academic medical center in Ann Arbor, Michigan.

PATIENTS

Adult and pediatric patients admitted between September 11, 2019 and December 10, 2019 were included if they had an order placed for 1 of the following: (1) C. difficile enzyme immunoassay (EIA) in patients hospitalized >72 hours and received laxatives, oral contrast, or initiated tube feeds within the prior 48 hours, (2) repeat molecular multiplex gastrointestinal pathogen panel (GIPAN) testing, or (3) GIPAN testing in patients hospitalized >72 hours.

INTERVENTION

A best-practice alert prompting prior authorization by the antimicrobial stewardship program (ASP) for EIA or GIPAN testing was implemented. Approval required the provider to page the ASP pharmacist and discuss rationale for testing. The provider could not proceed with the order if ASP approval was not obtained.

RESULTS

An average of 2.5 requests per day were received over the 3-month intervention period. The weekly rate of EIA and GIPAN orders per 1,000 patient days decreased significantly from 6.05 ± 0.94 to 4.87 ± 0.78 (IRR, 0.72; 95% CI, 0.56-0.93; P = .010) and from 1.72 ± 0.37 to 0.89 ± 0.29 (IRR, 0.53; 95% CI, 0.37-0.77; P = .001), respectively.

CONCLUSIONS

We identified an efficient, effective C. difficile and GIPAN diagnostic stewardship approval model.

Decreasing Duplicative Imaging: Inpatient and Emergency Medicine Abdominal Ultrasound Within 72 Hours of Abdominal CT

PURPOSE

The aim of this project was to reduce abdominal ultrasound examinations in patients who had undergone abdominal CT within 72 hours previously.

METHODS

A best practice advisory (BPA) was created in the electronic medical record to advise against the use of abdominal ultrasound in adult inpatients and emergency department patients who had undergone abdominal CT within the preceding 72 hours. Acceptable acknowledgment reasons to proceed with the order were made available if providers chose to override. Frequency of BPA firing and subsequent ordering behavior were evaluated 6 months after integration of the BPA into the electronic medical record. Chart review was conducted for 100 patients whose orders were placed through an override of the alert to determine if the ultrasound study added value and for all patients whose ultrasound studies were canceled to confirm that patient care was not compromised by omitting the ultrasound study.

RESULTS

In the first 6 months, a total of 614 inpatient and emergency department abdominal ultrasound orders triggered the BPA. A total of 16% of orders (n = 96) were canceled by the provider after the BPA, reflecting 518 overrides. The majority of retained orders were to evaluate the gallbladder (44% [227 of 518]). Chart review confirmed utility for gallbladder imaging and that the canceled ultrasound examinations would not have contributed value to patients' care.

CONCLUSIONS

A recently performed abdominal CT scan may obviate the need for inpatient and emergency department abdominal ultrasound, particularly in the setting of hospital-acquired acute kidney injury. A BPA resulted in only 16% of orders' being canceled, whereas chart review revealed a much larger opportunity to avoid duplicative imaging.

Patient Outcomes With Prevented vs Negative Clostridioides difficile Tests Using a Computerized Clinical Decision Support Tool

Background

Overtesting and overdiagnosis of Clostridioides difficile infection are suspected to be common. Reducing inappropriate testing through interventions designed to promote evidence-based diagnostic testing (ie, diagnostic stewardship) may improve C. difficile test utilization. However, the safety of these interventions is not well understood despite the potential risk for missed or delayed diagnoses.

Methods

This retrospective case-control study examined the outcomes of patients admitted to the University of Virginia Medical Center following introduction of a computerized clinical decision support tool without hard-stops designed to reduce inappropriate tests. Outcomes were compared between patients with a prevented C. difficile nucleic acid amplification test and those with a negative result. Chart reviews were performed for patients with a subsequent positive within 7 days, as well as those patients who received C. difficile-active antibiotics after implementation of the computerized clinical decision support tool.

Results

Multivariate analysis of 637 cases (490 negative, 147 prevented) showed that a prevented test was not significantly associated with the primary composite outcome (inpatient mortality or intensive care unit transfer) compared with a negative test (adjusted odds ratio, 0.912; P = .747). Fifty-four of 147 (37%) prevented tests were followed by a completed test within 7 days; 11 of these results were positive, resulting in a potential delay in diagnosis. Individual case reviews found that either clinical changes warranted the delay in testing or no adverse events occurred attributable to C. difficile infection. C. difficile treatment without a positive test was not identified.

Conclusions

Diagnostic stewardship of C. difficile testing using computerized clinical decision support may be both safe and effective for reducing inappropriate inpatient testing.

The Role of Diagnostic Stewardship in Clostridioides difficile Testing: Challenges and Opportunities

PURPOSE OF REVIEW

Accurate and timely diagnosis of Clostridioides difficile infection (CDI) is imperative to prevent C. difficile transmission and reduce morbidity and mortality due to CDI, but CDI laboratory diagnostics are complex. The purpose of this article is to review the role of laboratory tests in the diagnosis of CDI, and the role of diagnostic stewardship in optimization of C. difficile testing.

RECENT FINDINGS

Results from C. difficile diagnostic tests should be interpreted with an understanding of the strengths and limitations inherent in each testing approach. Use of highly sensitive molecular diagnostic tests without accounting for clinical signs and symptoms may lead to over-diagnosis of CDI and increased facility CDI rates. Current guidelines recommend a two-step, algorithmic approach for testing. Diagnostic stewardship interventions, such as education, order sets, order search menus, reflex orders, hard and soft stop alerts, electronic references, feedback and benchmarking, decision algorithms, and predictive analytics may help improve use of C. difficile laboratory tests and CDI diagnosis. The diagnostic stewardship approaches with the highest reported success rates include computerized clinical decision support (CCDS) interventions, face-to-face feedback, and real-time evaluations.

SUMMARY

CDI is a clinical diagnosis supported by laboratory findings. Together, clinical evaluation combined with diagnostic stewardship can optimize the accurate diagnosis of CDI.