Considerations from the College of American Pathologists for Implementation of an Assay for SARS-CoV-2 Testing after a Change in Regulatory Status.

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.

Searching for a Potential Algorithm for Clostridium difficile Testing at a Tertiary Care Hospital: Does Toxin Enzyme Immunoassay Testing Help?

Clostridium difficile is a major contributor to morbidity and mortality in the United States. Methods for identifying the organism in stool include molecular platforms, enzyme immunoassays (EIAs) for toxin, and culture. Controversy persists over whether molecular tests are too sensitive at identifying C. difficile, and there are questions about how additional laboratory information could inform clinical management and reduce over treatment. The aim of this study was to assess whether clinical factors are related to the toxin status of patients and whether information about toxin status could potentially inform clinical management of patients. A total of 201 PCR-positive C. difficile stool samples from adult patients at our institution underwent EIA toxin testing. Clinical and laboratory data were collected, and the percentage of PCR-positive/EIA-positive (PCR+/EIA+) patients and PCR+ and EIA-negative (PCR+/EIA-) patients was calculated. Of the 201 samples, 47% were EIA positive and 53% were EIA negative. Although PCR+/EIA+ patients were more likely to have had a prior C. difficile infection (P = 0.015), there was no statistical difference between the additional data collected that correlated with a positive EIA result. We were unable to show that patients with an EIA+ result had worse clinical parameters than those with EIA- results and concluded that establishing a testing algorithm that included both PCR and EIA testing would not change the clinical management of patients at our hospital.

Disseminated cutaneous Curvularia infection in an immunocompromised host; diagnostic challenges and experience with voriconazole.

An increasing spectrum and number of opportunistic fungal pathogens have been reported to cause disease in humans over the past decade. Disseminated phaeohyphomycoses caused by rare dematiaceous molds in immunocompromised patients have a high mortality rate and are increasingly reported in the literature. Early diagnosis of disseminated phaehyphomycosis is critical especially in neutropenic patients but can be hindered by the low sensitivity of fungal blood cultures and low clinical suspicion. Cutaneous manifestations are often the earliest sign of disease and conducting a thorough skin exam in febrile neutropenic patients can lead to more rapid diagnosis and initiation of treatment. PCR amplification and sequencing of mold RNA extracted from paraffin-embedded tissue can be useful for diagnosing rare fungal infections when negative fungal cultures preclude morphologic diagnosis. Effective treatment for disseminated phaehyphomycosis is lacking and there is a need to report experiences with the use of newer antifungals.

Testing of integrated human papillomavirus mRNA decreases colposcopy referrals: could a change in human papillomavirus detection methodology lead to more cost-effective patient care?

OBJECTIVES: This study investigates potential colposcopy referral rates, as per the latest American Society for Colposcopy and Cervical Pathology recommendations, following the change in high-risk human papillomavirus (HR-HPV) detection methodology from Hybrid Capture 2 (HC2) to APTIMA at our institution. STUDY DESIGN: Rates of colposcopy referral were compared between two cohorts, each comprising all Pap samples with a diagnosis of atypical squamous cells of undetermined significance (ASCUS) tested for HR-HPV in our laboratory during a 12-month period. Cohorts I and II included Pap samples tested with HC2 (n = 1,856) and APTIMA (n = 1,651), respectively. The rates of quantity not sufficient (QNS) results were determined for all Pap samples during the same time periods. RESULTS: The proportion of HR-HPV-positive Pap samples with an ASCUS diagnosis was significantly lower with APTIMA (42%) than with HC2 (53%; p < 0.0001). APTIMA also resulted in a significantly lower QNS rate among all Pap samples (0.42 vs. 4.3% with HC2; p < 0.0001). CONCLUSION: The change in HR-HPV detection methodology from HC2 to APTIMA has led to a 21% reduction in colposcopy referrals and a 90% decrease in QNS rates at our institution. The new methodology has resulted in more cost-effective patient care and fewer insufficient samples requiring repeat HR-HPV testing.

High Prevalence of Multistep Algorithms in Diagnostic Clostridioides difficile Laboratory Testing.

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.

Evaluation of the Verigene Gram-positive blood culture nucleic acid test for rapid detection of bacteria and resistance determinants.

Rapid identification of pathogens from blood cultures can decrease lengths of stay and improve patient outcomes. We evaluated the accuracy of the Verigene Gram-positive blood culture (BC-GP) nucleic acid test for investigational use only (Nanosphere, Inc., Northbrook, IL) for the identification of Gram-positive bacteria from blood cultures. The detection of resistance genes (mecA in Staphylococcus aureus and Staphylococcus epidermidis and vanA or vanB in Enterococcus faecium and Enterococcus faecalis) by the BC-GP assay also was assessed. A total of 186 positive blood cultures (in BacT/Alert FA bottles) with Gram-positive cocci observed with Gram staining were analyzed using the BC-GP assay. The BC-GP results were compared with the identification and susceptibility profiles obtained with routine methods in the clinical laboratory. Discordant results were arbitrated with additional biochemical, cefoxitin disk, and repeat BC-GP testing. The initial BC-GP organism identification was concordant with routine method results for 94.6% of the blood cultures. Only 40% of the Streptococcus pneumoniae identifications were correct. The detection of the mecA gene for 69 blood cultures with only S. aureus or S. epidermidis was concordant with susceptibility testing results. For 3 of 6 cultures with multiple Staphylococcus spp., mecA detection was reported but was correlated with oxacillin resistance in a species other than S. aureus or S. epidermidis. The detection of vanA agreed with susceptibility testing results for 45 of 46 cultures with E. faecalis or E. faecium. Comparison of the mean times to results for each organism group showed that BC-GP results were available 31 to 42 h earlier than phenotypic identifications and 41 to 50 h earlier than susceptibility results.

Bloodstream infection caused by nontoxigenic Corynebacterium diphtheriae in an immunocompromised host in the United States.

Corynebacterium species are well-known causes of catheter-related bloodstream infections. Toxigenic strains of Corynebacterium diphtheriae cause respiratory diphtheria. We report a bloodstream infection caused by a nontoxigenic strain of C. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria.

Impact of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) vaccination on the incidence of coronavirus disease 2019 (COVID-19) among healthcare workers at an academic medical center in Vermont.

Infection prevention strategies and vaccination reduce risk of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) transmission to healthcare workers (HCWs). We describe coronavirus disease 2019 (COVID-19) incidence and vaccination rates in a cohort of HCWs at the University of Vermont Medical Center. Before vaccines, the HCW COVID-19 incidence paralleled that of the State of Vermont; after vaccination, incidence fell and remained low.

Anatomy of a Cyberattack: Part 2: Managing a Clinical Pathology Laboratory During 25 Days of Downtime.

OBJECTIVES: Our academic health care institution was the victim of a cyberattack that led to a complete shutdown of major patient care, operational, and communication systems, including our electronic health record (EHR), laboratory information system, pharmacy, scheduling, billing and coding, imaging software, internet, hospital shared computer drives, payroll, and digital communications. The EHR remained down for 25 days, significantly affecting our clinical pathology (CP) laboratory operations. METHODS: During the downtime, our CP laboratory incorporated manual interventions for patient specimen testing, recruited additional staff for reporting results, and employed multiple communication modalities to support patient care. The crisis required a swift response, employing innovative approaches to mitigate patient harm; regular, multidisciplinary engagement; and consistent, broad-reaching communications. CP leadership worked with hospital administration, staff, and our referral clients to provide the timely laboratory results needed for acute patient care. RESULTS: During this downtime, the laboratory lacked accurate information about the number of patient samples diverted to other laboratories, the number of specimens processed, and the number of test results reported. CONCLUSIONS: This paper focuses on the approaches the CP division took to develop and maintain downtime operations. Laboratories should consider these strategies in preparation for a prolonged downtime.

Raising the Bar: Improving Antimicrobial Resistance Detection by Clinical Laboratories by Ensuring Use of Current Breakpoints.

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 (P < .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.

All Hands-On Deck and All Decks on Hand: Surmounting Supply Chain Limitations During the COVID-19 Pandemic.

Testing during the COVID-19 pandemic has been crucial to public health surveillance and clinical care. Supply chain constraints-spanning limitations in testing kits, reagents, pipet tips, and swabs availability-have challenged the ability to scale COVID-19 testing. During the early months, sample collection kits shortages constrained planned testing expansions. In response, the University of Vermont Medical Center, University of Vermont College of Medicine, Vermont Department of Health Laboratory, Aspenti Health, and providers across Vermont including 16 area hospitals partnered to surmount these barriers. The primary objectives were to increase supply availability and manage utilization. Within the first month of Vermont's stay-at-home order, the University of Vermont Medical Center laboratory partnered with College of Medicine to create in-house collection kits, producing 5000 per week. University of Vermont Medical Center reassigned 4 phlebotomists, laboratory educators, and other laboratory staff, who had reduced workloads, to participate (requiring a total of 5.3-7.6 full-time equivalent (FTE) during the period of study). By August, automation at a local commercial laboratory produced 22,000 vials of media in one week (reducing the required personnel by 1.2 FTE). A multisite, cross-institutional approach was used to manage specimen collection kit utilization across Vermont. Hospital laboratory directors, managers, and providers agreed to order only as needed to avoid supply stockpiles and supported operational constraints through ongoing validations and kit assembly. Throughout this pandemic, Vermont has ranked highly in number of tests per million people, demonstrating the value of local collaboration to surmount obstacles during disease outbreaks and the importance of creative allocation of resources to address statewide needs.

Promoting appropriate utilisation of laboratory tests for inflammation at an academic medical centre.

Erythrocyte sedimentation rate (ESR) and C reactive protein (CRP) are commonly ordered in clinical practice to evaluate for inflammation. CRP is a more sensitive and specific test for detecting acute phase inflammation, and the American Society for Clinical Pathology recommends ordering CRP rather than ESR to detect acute phase inflammation in patients with undiagnosed conditions. We sought to understand CRP and ESR ordering practices and reduce unnecessary use of ESR testing at our academic medical centre. We surveyed physician leaders in clinical areas with high utilisation of ESR testing to understand the drivers of potential overutilisation of these tests. Based on survey responses, we designed an intervention focused on education, clinical decision support within the electronic medical record and quarterly audit and feedback. We evaluated appropriateness of ESR ordering before and after the intervention via structured chart audit. Comparison of monthly rates of ESR tests during the preintervention and postintervention periods was conducted using interrupted time series analysis. Clinical habit and ease of test ordering were identified as key drivers of ESR overuse. Compared with the preintervention period, we observed a 33% reduction in the number of ESR tests per month and a 25% reduction in combined CRP and ESR tests per month during the postintervention period. This reduction corresponded to an annual avoidance of 2633 ESR tests with a corresponding estimated direct cost avoidance of $23 701 annually. Although the rate of ESR testing decreased, there was no significant improvement in the clinical appropriateness of residual ESR test ordering following the intervention. A multifaceted intervention was associated with significant decreases in unnecessary ESR tests and concurrent ESR and CRP tests at our academic medical centre. Despite these reductions, there are continued opportunities to reduce inappropriate ESR testing.