ABSTRACT
CONTEXT.: Laboratory testing practices for diagnosis of Clostridioides difficile infection (CDI) have evolved in response to published guidelines, availability of highly sensitive nucleic acid amplification tests (NAATs), perceived problems with the specificity of NAATs, and CDI reporting requirements. OBJECTIVE.: To assess the current state of laboratory practice for diagnostic CDI testing. DESIGN.: An optional 8-item supplemental questionnaire was distributed in December 2019 to the 1374 laboratories participating in the College of American Pathologists C difficile Detection (CDF) proficiency testing program challenge CDF-C. RESULTS.: Of 1374 CDF-C participants, 1160 (84.4%) responded, predominantly representing laboratories based in the United States (1077 of 1160; 92.8%). The majority reported using a multistep testing algorithm (684 of 1159; 59.0%). Initial testing with a glutamate dehydrogenase and toxin A/B combination test followed by NAAT for discrepant results was the most common testing method (360 of 1146; 31.4%). NAAT alone (299 of 1146; 26.1%) was next, then NAAT followed by an assay that included toxin A/B enzyme immunoassay if NAAT is positive (258 of 1146; 22.5%). Only 5.4% (62 of 1146) reported using toxin A/B immunoassay alone. Most respondents (1093 of 1131; 96.6%) reported rejecting CDI tests on formed stool, but rejection of CDI testing in pediatric patients was uncommon (211 of 1131; 18.7%). Rejection of CDI testing in patients using laxatives was reported more often by US-based respondents (379 of 1054 [36.0%] versus 9 of 77 [11.7%], P < .001). CONCLUSIONS.: Multistep algorithms for CDI diagnosis are widely used in line with published recommendations. Most respondents reported rejection of formed stool for CDI testing, but few reported rejection of testing in infants and patients taking laxatives, suggesting these may be areas of opportunity for laboratories to pursue in improving CDI testing practices.
Subject(s)
Bartonella Infections , Bartonella quintana , Bartonella , Endocarditis, Bacterial , Endocarditis , Trench Fever , Humans , Bartonella quintana/genetics , RNA, Ribosomal, 16S/genetics , Mitral Valve , Endocarditis, Bacterial/diagnosis , Aortic Valve , Endocarditis/diagnosis , Bartonella/genetics , Trench Fever/diagnosisABSTRACT
The coronavirus disease 2019 (COVID-19) pandemic has demonstrated the importance of stewardship of viral diagnostic tests to aid infection prevention efforts in healthcare facilities. We highlight diagnostic stewardship lessons learned during the COVID-19 pandemic and discuss how diagnostic stewardship principles can inform management and mitigation of future emerging pathogens in acute-care settings. Diagnostic stewardship during the COVID-19 pandemic evolved as information regarding transmission (eg, routes, timing, and efficiency of transmission) became available. Diagnostic testing approaches varied depending on the availability of tests and when supplies and resources became available. Diagnostic stewardship lessons learned from the COVID-19 pandemic include the importance of prioritizing robust infection prevention mitigation controls above universal admission testing and considering preprocedure testing, contact tracing, and surveillance in the healthcare facility in certain scenarios. In the future, optimal diagnostic stewardship approaches should be tailored to specific pathogen virulence, transmissibility, and transmission routes, as well as disease severity, availability of effective treatments and vaccines, and timing of infectiousness relative to symptoms. This document is part of a series of papers developed by the Society of Healthcare Epidemiology of America on diagnostic stewardship in infection prevention and antibiotic stewardship.1.
Subject(s)
COVID-19 , Communicable Diseases, Emerging , Humans , COVID-19/diagnosis , COVID-19/prevention & control , COVID-19/epidemiology , Pandemics/prevention & control , SARS-CoV-2 , Communicable Diseases, Emerging/diagnosis , Communicable Diseases, Emerging/epidemiology , Communicable Diseases, Emerging/prevention & control , Contact Tracing , COVID-19 TestingABSTRACT
We provide an overview of diagnostic stewardship with key concepts that include the diagnostic pathway and the multiple points where interventions can be implemented, strategies for interventions, the importance of multidisciplinary collaboration, and key microbiologic diagnostic tests that should be considered for diagnostic stewardship. The document focuses on microbiologic laboratory testing for adult and pediatric patients and is intended for a target audience of healthcare workers involved in diagnostic stewardship interventions and all workers affected by any step of the diagnostic pathway (ie, ordering, collecting, processing, reporting, and interpreting results of a diagnostic test). This document was developed by the Society for Healthcare Epidemiology of America Diagnostic Stewardship Taskforce.
Subject(s)
Health Facilities , Health Personnel , Child , Humans , Anti-Bacterial Agents/therapeutic use , Delivery of Health CareABSTRACT
BACKGROUND: Antimicrobial resistance (AMR) is a pressing global challenge detected by antimicrobial susceptibility testing (AST) performed by clinical laboratories. AST results are interpreted using clinical breakpoints, which are updated to enable accurate detection of new and emerging AMR. Laboratories that do not apply up-to-date breakpoints impede global efforts to address the AMR crisis, but the extent of this practice is poorly understood. METHODS: A total of 1490 clinical laboratories participating in a College of American Pathologists proficiency testing survey for bacterial cultures were queried to determine use of obsolete breakpoints. RESULTS: Between 37.9% and 70.5% of US laboratories reported using obsolete breakpoints for the antimicrobials that were queried. In contrast, only 17.7%-43.7% of international laboratories reported using obsolete breakpoints (Pâ <â .001 for all comparisons). Use of current breakpoints varied by AST system, with more laboratories reporting use of current breakpoints in the US if the system had achieved US Food and Drug Administration clearance with current breakpoints. Among laboratories that indicated use of obsolete breakpoints, 55.9% had no plans to update to current standards. The most common reason cited was manufacturer-related issues (51.3%) and lack of internal resources to perform analytical validation studies to make the update (23.4%). Thirteen percent of laboratories indicated they were unaware of breakpoint changes or the need to update breakpoints. CONCLUSIONS: These data demonstrate a significant gap in the ability to detect AMR in the US, and to a lesser extent internationally. Improved application of current breakpoints by clinical laboratories will require combined action from regulatory agencies, laboratory accreditation groups, and device manufacturers.
ABSTRACT
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.
Subject(s)
Antimicrobial Stewardship , Clostridioides difficile , Clostridium Infections , Clostridioides , Clostridium Infections/diagnosis , Clostridium Infections/drug therapy , Clostridium Infections/prevention & control , Hospitals , HumansABSTRACT
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.
Subject(s)
Antimicrobial Stewardship , Clostridium Infections , Communicable Diseases , Sepsis , Anti-Bacterial Agents/therapeutic use , Antimicrobial Stewardship/methods , Humans , Sepsis/drug therapyABSTRACT
The U.S. Food & Drug Administration (FDA) regulates the marketing of manufacturers' in vitro diagnostic tests (IVDs), including assays for the detection of SARS-CoV-2. The U.S. government's Clinical Laboratory Improvement Amendments (CLIA) of 1988 regulates the studies that a clinical diagnostic laboratory needs to perform for an IVD before placing it into use. Until recently, the FDA has authorized the marketing of SARS-CoV-2 IVDs exclusively through the Emergency Use Authorization (EUA) pathway. The regulatory landscape continues to evolve, and IVDs will eventually be required to pass through conventional non-EUA FDA review pathways once the emergency declaration is terminated, in order to continue to be marketed as an IVD in the United States. When FDA regulatory status of an IVD changes or is anticipated to change, the laboratory should review manufacturer information and previously performed internal verification studies to determine what, if any, additional studies are needed before implementing the non-EUA version of the IVD in accordance with CLIA regulations. Herein, the College of American Pathologists' Microbiology Committee provides guidance for how to approach regulatory considerations when an IVD is converted from EUA to non-EUA status.
Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19 Testing , Humans , Pathologists , United States , United States Food and Drug AdministrationABSTRACT
Fungal infections are a rising threat to our immunocompromised patient population, as well as other nonimmunocompromised patients with various medical conditions. However, little progress has been made in the past decade to improve fungal diagnostics. To jointly address this diagnostic challenge, the Fungal Diagnostics Laboratory Consortium (FDLC) was recently created. The FDLC consists of 26 laboratories from the United States and Canada that routinely provide fungal diagnostic services for patient care. A survey of fungal diagnostic capacity among the 26 members of the FDLC was recently completed, identifying the following diagnostic gaps: lack of molecular detection of mucormycosis; lack of an optimal diagnostic algorithm incorporating fungal biomarkers and molecular tools for early and accurate diagnosis of Pneumocystis pneumonia, aspergillosis, candidemia, and endemic mycoses; lack of a standardized molecular approach to identify fungal pathogens directly in formalin-fixed paraffin-embedded tissues; lack of robust databases to enhance mold identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry; suboptimal diagnostic approaches for mold blood cultures, tissue culture processing for Mucorales, and fungal respiratory cultures for cystic fibrosis patients; inadequate capacity for fungal point-of-care testing to detect and identify new, emerging or underrecognized, rare, or uncommon fungal pathogens; and performance of antifungal susceptibility testing. In this commentary, the FDLC delineates the most pressing unmet diagnostic needs and provides expert opinion on how to fulfill them. Most importantly, the FDLC provides a robust laboratory network to tackle these diagnostic gaps and ultimately to improve and enhance the clinical laboratory's capability to rapidly and accurately diagnose fungal infections.
Subject(s)
Laboratories , Mucorales , Canada , Clinical Laboratory Techniques , Expert Testimony , HumansABSTRACT
This survey investigated diagnostic and antimicrobial stewardship practices related to molecular respiratory panel testing in adults with lower respiratory tract infections at acute care hospitals. Most respondents reported use of rapid respiratory panels, but related stewardship practices were uncommon and the real-world impact of respiratory panels were difficult to quantify.
Subject(s)
Antimicrobial Stewardship , Respiratory Tract Infections , Adult , Anti-Bacterial Agents/therapeutic use , Humans , Molecular Diagnostic Techniques , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/drug therapy , Surveys and QuestionnairesABSTRACT
BACKGROUND: Children who develop malaria after returning to a setting in which the disease is not endemic are at high risk for critical delays in diagnosis and initiation of antimalarial therapy. We assessed the clinical impact of the implementation of malaria rapid diagnostic testing (RDT) on the management of children with malaria at an urban US children's hospital that serves a large immigrant population. METHODS: This was a retrospective cohort study of all children diagnosed with laboratory-confirmed malaria at the Children's Hospital of Philadelphia (CHOP) between 2000 and 2014. RDT using a US Food and Drug Administration-approved immunochromatographic assay was introduced at CHOP on August 1, 2007. We compared clinical management and outcomes of patients with malaria diagnosed before and after RDT introduction. RESULTS: We analyzed 82 pediatric malaria cases (32 before and 50 after RDT implementation). The majority of these patients had traveled to West Africa (91.5%) and were infected with Plasmodium falciparum (80.5%). The mean time to a positive result decreased from 10.4 to 0.9 hours (P < .001) after the introduction of RDT for patients with P falciparum. The mean time to antimalarial therapy decreased from 13.1 to 6.9 hours (P =; .023) in hospitalized patients. We found no significant reduction in the mean number of clinical signs of severe malaria between 0 and 48 hours of hospitalization and no difference in the need for exchange transfusion, time to resolution of parasitemia, or length of hospital stay. CONCLUSIONS: Implementation of RDT for malaria was associated with shorter times to malaria diagnosis and initiation of antimalarial therapy. The results of this study support RDT in the optimal management of patients with malaria who present in settings in which the disease is not endemic.
Subject(s)
Antigens, Protozoan/blood , Immunoassay , Malaria/diagnosis , Africa, Western , Child , Child, Preschool , Female , Hospitals, Pediatric , Humans , Length of Stay , Linear Models , Malaria/epidemiology , Malaria, Falciparum/diagnosis , Malaria, Falciparum/epidemiology , Male , Parasitemia/blood , Parasitemia/diagnosis , Patient Acuity , Philadelphia/epidemiology , Plasmodium/immunology , Plasmodium falciparum/immunology , Protozoan Proteins/immunology , Retrospective Studies , Sensitivity and Specificity , Time-to-Treatment , TravelABSTRACT
PURPOSE OF REVIEW: Ventilator-associated pneumonia (VAP) is one of the most common infections in the ICU. Prompt diagnosis is vital as mortality increases with delayed antibiotic therapy. However, accurate diagnosis is challenging due to non-specific clinical features in a complicated patient cohort. Microbiological culture data remains a crucial aspect in confirming diagnosis. RECENT FINDINGS: Literature data comparing the benefit of invasive respiratory sampling to non-invasive is inconclusive. Differences in culturing practices translate in overidentification of organisms of unclear significance. Positive culture data in a low pre-test probability does not differentiate between true infection and colonization resulting in overtreatment. Furthermore, there are also opportunities for modifying the reporting of respiratory tract cultures that can better guide antimicrobial therapy. Under the umbrella of antimicrobial stewardship, diagnostic stewardship can be incorporated to create a systematic approach that would target culturing practices to match the right pre-test probability. Ideal outcome will be targeting cultures to the right patient population and minimizing unnecessary treatment.
ABSTRACT
We assessed whether implementation of matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry without antimicrobial stewardship support would impact antimicrobial utilization and clinical outcomes in inpatient pneumonia. Implementation significantly reduced time to organism identification and time to optimal therapy but did not have a detectable impact on clinical outcomes.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Pneumonia/diagnosis , Pneumonia/drug therapy , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Adult , Antimicrobial Stewardship , Humans , Inpatients , Length of Stay , Time-to-TreatmentABSTRACT
PURPOSE OF REVIEW: The primary purpose of this review is to provide a summary of new and emerging laboratory technologies and testing platforms that impact infection prevention and antimicrobial stewardship programs. This review also summarizes available data describing the clinical impact of implementing these new technologies. RECENT FINDINGS: While there is ample evidence that rapid organism identification technologies for positive blood cultures can ameliorate antimicrobial utilization, an assay that also provides expedited antimicrobial susceptibility testing results is now available and its clinical impact is under investigation. For C. difficile infection diagnosis, data related to performance and impact of "ultrasensitive" toxin assays is emerging in the literature although their role in C. difficile infection diagnosis remains unclear. For hospital-acquired pneumonia, a variety of rapid, automated, multiplexed, "pneumonia" panels have become commercially available and may impact surveillance definitions for ventilator-associated events. Finally, recent FDA clearance of various biochemical and molecular carbapenemase detection tests will facilitate rapid characterization of carbapenem-resistant organisms. Innovations in infectious diseases diagnostics have been making swift strides, broadening diagnostic scope; increasing accuracy and sensitivity; and reducing turnaround time. Many of these innovations directly impact infection prevention and antimicrobial stewardship operations. Close collaboration between infection control, antimicrobial stewardship, and the microbiology laboratory is necessary to ensure that new tests improve patient outcomes.
ABSTRACT
PURPOSE OF REVIEW: The current review summarizes advances in rapid diagnostic testing that impacts infection prevention and antimicrobial stewardship programs. RECENT FINDINGS: A variety of rapid diagnostic technologies to identify organisms in cultured blood are now available. When coupled with antimicrobial stewardship (ASP), these rapid technologies can optimize antimicrobial utilization and patient outcomes. Two rapid molecular panels that detect organisms related to pneumonia are available and may impact infection prevention surveillance definitions. Three molecular tests are available for the detection of meningitis and encephalitis pathogens. Still, the clinical impact of these broad, multiplexed panels need additional clarification. For Clostridioides difficile infections, ultrasensitive toxin A/B assays may provide enhanced sensitivity and specificity compared with enzyme immunoassay and molecular testing respectively. Finally, the adoption of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI TOF MS) for rapid organism identification is growing. Recent US Food and Drug Administration-clearance of a MALDI TOF MS platform for identification of Nocardia, Mycobacteria, and molds may expedite antimicrobial decisions for infections that traditionally required days to weeks for an identification. SUMMARY: Tests with broad diagnostic scope and swift turnaround time are rapidly entering the market. Many impact infection prevention and ASP programs. Collaboration with the microbiology laboratory is crucial to ensure that new tests successfully optimize patient care.
Subject(s)
Antimicrobial Stewardship , Infection Control , Infections/diagnosis , Infections/epidemiology , Anti-Infective Agents/pharmacology , Anti-Infective Agents/therapeutic use , Diagnostic Tests, Routine , Drug Resistance, Bacterial , Humans , Immunoassay , Infection Control/methods , Infections/drug therapy , Infections/etiology , Molecular Diagnostic Techniques , Sepsis/diagnosis , Sepsis/epidemiology , Sepsis/etiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationABSTRACT
PURPOSE OF REVIEW: Urinary tract infections (UTIs), including catheter-associated UTIs, are among the most common bacterial infections in both inpatient and outpatient settings. Diagnosis of true UTI remains a clinical challenge, and excessive antimicrobial treatment of asymptomatic bacteriuria (ASB) or contaminated urine cultures is common. RECENT FINDINGS: Challenges with the appropriate diagnosis of UTIs include the lack of specific signs and symptoms, no definitive diagnostic criteria, high incidence of ASB, contamination of samples, and frequent lack of indications for ordering urine cultures. Promising interventions include education and feedback, indication requirements when ordering cultures, and use of reflex culture policies that limit urine cultures. Antimicrobial and diagnostic stewardship interventions can work synergistically to decrease ordering of urine cultures without clear indication and prevent excessive antimicrobial administration in patients without clearly defined UTI.
ABSTRACT
This survey investigated interventions used by acute-care hospitals to reduce the detection of asymptomatic bacteriuria. Half of the respondents reported using reflex urine cultures but with varied urinalysis criteria and perceived outcomes. Other diagnostic stewardship interventions for urine culture ordering and specimen quality were less common.