CoaguChek and Coag-Sense PT2 Meter Point of Care INR Device Validation.

OBJECTIVE: To standardize international normalized ratio (INR) measurements and improve data integrity by enabling electronic result transmission for warfarin monitoring, two point-of-care (POC) devices were evaluated against an internal plasma INR reference method. METHODS: A multicenter study was pursued (January 24, 2022, through October 19, 2022) to compare concordance of two commercially available POC devices, Coag-Sense PT2 Meter (Coag-Sense) and CoaguChek XS Pro and Plus devices (CoaguChek), against an internal plasma INR method among patients treated with warfarin. Bias and linear regression analysis were assessed for these devices including dosing decision accuracy compared with plasma INR reference. RESULTS: Two hundred ninety-nine patients treated with warfarin across three Mayo Clinic sites agreed to participate. Atrial fibrillation (n=191, 63.9%), venous thromboembolism (n=65; 21.7%), and heart valve prosthesis (n=46; 15.4%) were common anticoagulant indications with a 2.5 INR target for 280 (93.6%) of patients. For the CoaguChek devices, 243 (81.3%) of values fell within 0.2 INR units with plasma INR referent and 285 (95.3%) within 0.4 units (R2=0.93). For the Coag-Sense device, 102 (34.1%) of values fell within 0.2 INR units and 180 (60.2%) within 0.4 INR units of plasma INR values, (R2=0.83; P<.0001). Using the plasma INR as the gold standard, appropriate dosing recommendations would have occurred for 292 (97.7%) of the CoaguChek and 244 (81.6%) of the Coag-Sense results. CONCLUSION: Compared with a plasma referent, INR values obtained from the CoaguChek devices exhibited less systematic bias compared with Coag-Sense measures. This translates to a greater percentage of concordant management decisions between POC and laboratory INR methods.

SARS-CoV-2 emergency use authorization published sensitivity differences do not correlate with positivity rate in a hospital/reference laboratory setting.

During the first year of the COVID-19 pandemic skyrocketing demand for testing in the United States, coupled with supply chain issues, necessitated the use of multiple SARS-CoV-2 molecular testing platforms at many health centers. At our institution these platforms consisted of 8 ordered services for sample triage, using 9 emergency use authorized (EUA) SARS-CoV-2 RNA nucleic acid amplification tests resulting in 10 possible ordered service/EAU combinations. Here we review the results of the first ∼2.9 million samples tested and note the variability in positivity rates. We conclude that differences in reported limit of detection did not translate to differences in positivity rate or show correlation to discordant results observed. This highlights the importance of balancing patient testing capacity needs with the desire to have more sensitive tests.

Evaluation of the analytical sensitivity of ACON and LumiraDx SARS-CoV-2 rapid antigen tests using samples with presumed Omicron variant.

BACKGROUND: Analytical sensitivity of 2 rapid antigen tests was evaluated for detection of presumed SARS-CoV-2 Omicron variants and earlier variants of concern. METHODS: A total of 152 SARS-CoV-2 RNA positive samples (N and ORF1ab positive but S gene negative) were tested for SARS-CoV-2 antigen by ACON lateral flow and LumiraDx fluorescence immunoassays. Sensitivity within 3 viral load ranges was compared among these 152 samples and 194 similarly characterized samples collected prior to the circulation of the Delta variant (pre-Delta). RESULTS: Antigen was detected in >95% of pre-Delta and presumed Omicron samples for both tests at viral loads >500,000 copies/mL, and 65 to 85% of samples with 50,000-500,000 copies/mL. At viral load <50,000 copies/mL, antigen tests showed better sensitivity in detecting pre-Delta compared to Omicron variants. LumiraDx was more sensitive than ACON at low viral load. CONCLUSIONS: Antigen tests had decreased sensitivity for detecting presumed Omicron compared to pre-Delta variants at low viral load.

Cardiac troponin measurement at the point of care: educational recommendations on analytical and clinical aspects by the IFCC Committee on Clinical Applications of Cardiac Bio-Markers (IFCC C-CB).

The International Federation of Clinical Chemistry and Laboarator Medicine (IFCC) Committee on Clinical Applications of Cardiac Bio-Markers (C-CB) has provided evidence-based educational resources to aid and improve the understanding of important analytical and clinical aspects of cardiac biomarkers. The present IFCC C-CB educational report focuses on recommendations for appropriate use, analytical performance, and gaps in clinical studies related to the use of cardiac troponin (cTn) by point of care (POC) measurement, often referred to as a point of care testing (POCT). The use of high-sensitivity (hs)-cTn POC devices in accelerated diagnostic protocols used in emergency departments or outpatient clinics investigating acute coronary syndrome has the potential for improved efficacy, reduction of length of stay and reduced costs in the health care system. POCT workflow integration includes location of the instrument, assignment of collection and testing responsibility to (non-lab) staff, instrument maintenance, in-service and recurrent training, quality control, proficiency assessments, discrepant result trapping, and troubleshooting and inventory management.

Authorized SARS-CoV-2 molecular methods show wide variability in the limit of detection.

On February 29th, 2020, the U.S. Food and Drug Administration issued the first Emergency Use Authorization (EUA) for a SARS-CoV-2 assay outside of the U.S. Centers for Disease Control and Prevention. As of May 3rd, 2021, 289 total EUAs have been granted. Like influenza, there is no standard for defining limit of detection (LoD), but rather guidance that analytical sensitivity/LoD be established as the level that gives a 95% detection rate in at least 20 replicates. Here we compare the performance characteristics of SARS-CoV-2 tests receiving EUA by standardizing sensitivity to a common unit of measure and assess the variability in LoD between tests. Additionally, we looked at factors that may impact sensitivities due to lack of standardization of the test development process and compare results for a standardized reference panel for comparative analysis within a subset of EUA tests offered by the U.S. Food and Drug Administration.

Evaluation of the Visby medical COVID-19 point of care nucleic acid amplification test.

Rapid and widespread diagnostic testing is critical to providing timely patient care and reducing transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Recently, the Visby Medical COVID-19 point of care (POC) test was granted emergency use authorization (EUA) for qualitative detection of SARS-CoV-2 nucleic acid at the point of care. We evaluated its performance characteristics using residual specimens (n = 100) collected from Mayo Clinic patients using nasopharyngeal (NP) swabs and placed in viral transport media (VTM). The same specimen was tested using both the laboratory reference method (RT-qPCR) and Visby test. The reference methods utilized included a laboratory developed test with EUA (Mayo Clinic Laboratories, Rochester, MN) using the TaqMan assay on a Roche Light Cycler 480 or a commercially available EUA platform (cobas® SARS-CoV-2; Roche Diagnostics, Indianapolis, IN). Positive, negative, and overall percent agreement between the Visby COVID-19 test and the reference method were calculated. Additionally, the limit of detection (LoD) claimed by the manufacturer (1112 copies/mL) was verified with serial dilutions of heat inactivated virus. The Visby COVID-19 test correctly identified 29/30 positive samples and 69/70 negative samples, resulting in an overall concordance of 98.0%, positive percent agreement of 96.7%, and negative percent agreement of 98.6%. The abbreviated LoD experiment showed that the analytical sensitivity of the method is as low as or lower than 500 copies/mL. Our study demonstrated that Visby COVID-19 is well-suited to address rapid SARS-CoV-2 testing needs. It has high concordance with central laboratory-based RT-qPCR methods, a low rate of invalid results, and superior analytical sensitivity to some other EUA POC devices.

Practical Anemia Bundle for Sustained Blood Recovery (PABST-BR) in critical illness: a protocol for a randomised controlled trial.

INTRODUCTION: Anaemia is highly prevalent in critical illness and is associated with impaired outcomes during and after hospitalisation. However, the impact of interventions designed to attenuate or treat anaemia during critical illness on post-hospitalisation haemoglobin recovery and functional outcomes is unclear. METHODS AND ANALYSIS: The Practical Anemia Bundle for Sustained Blood Recovery (PABST-BR) clinical trial is a pragmatic, open-label, parallel group, single-centre, randomised clinical trial assessing the impact of a multifaceted anaemia prevention and treatment strategy versus standard care for improvement of haemoglobin concentrations and functional outcomes after critical illness. The intervention, which will be delivered early in critical illness for those with moderate-to-severe anaemia (ie, haemoglobin <100 g/L), includes three components: (1) optimised phlebotomy, (2) clinical decision support and (3) pharmacological anaemia treatment directed at the underlying aetiology of anaemia. In-person assessments will occur at 1 and 3 months post-hospitalisation for laboratory evaluations and multidimensional functional outcome assessments. The primary outcome is differences in haemoglobin concentrations between groups, with secondary endpoints of anaemia-related fatigue, physical function, cognition, mental health, quality of life, phlebotomy volumes and frequency, transfusions, readmissions and mortality through 1-year post-hospitalisation. ETHICS AND DISSEMINATION: The study has been approved by the Institutional Review Board of the Mayo Clinic in Minnesota, USA. A Data Safety Monitoring Plan has been created in accordance with the policies of the Institutional Review Board and the study funder, the National Heart, Lung and Blood Institute of the National Institutes of Health (NIH). The study will comply with NIH data sharing and dissemination policies. Results will be presented at national and international meetings and published in peer-reviewed journals. Designing and testing strategies to optimise haemoglobin recovery and improve functional outcomes after critical illness remain important research gaps. The PABST-BR trial will inform the development of a larger multicentre clinical trial. TRIAL REGISTRATION NUMBER: NCT05167734.

AACC Guidance Document on the Use of Point-of-Care Testing in Fertility and Reproduction.

BACKGROUND: The AACC Academy revised the reproductive testing section of the Laboratory Medicine Practice Guidelines: Evidence-Based Practice for Point-of-Care Testing (POCT) published in 2007. METHODS: A panel of Academy members with expertise in POCT and laboratory medicine was formed to develop guidance for the use of POCT in reproductive health, specifically ovulation, pregnancy, premature rupture of membranes (PROM), and high-risk deliveries. The committee was supplemented with clinicians having Emergency Medicine and Obstetrics/Gynecology training. RESULTS: Key recommendations include the following. First, urine luteinizing hormone (LH) tests are accurate and reliable predictors of ovulation. Studies have shown that the use of ovulation predicting kits may improve the likelihood of conception among healthy fertile women seeking pregnancy. Urinary LH point-of-care testing demonstrates a comparable performance among other ovulation monitoring methods for timing intrauterine insemination and confirming sufficient ovulation induction before oocyte retrieval during in vitro fertilization. Second, pregnancy POCT should be considered in clinical situations where rapid diagnosis of pregnancy is needed for treatment decisions, and laboratory analysis cannot meet the required turnaround time. Third, PROM testing using commercial kits alone is not recommended without clinical signs of rupture of membranes, such as leakage of amniotic fluid from the cervical opening. Finally, fetal scalp lactate is used more than fetal scalp pH for fetal acidosis due to higher success rate and low volume of sample required. CONCLUSIONS: This revision of the AACC Academy POCT guidelines provides recommendations for best practice use of POCT in fertility and reproduction.

A Contemporary Analysis of Phlebotomy and Iatrogenic Anemia Development Throughout Hospitalization in Critically Ill Adults.

BACKGROUND: Anemia is common in critically ill patients and may be exacerbated through phlebotomy-associated iatrogenic blood loss. Differences in phlebotomy practice across patient demographic characteristics, clinical features, and practice environments are unclear. This investigation provides a comprehensive description of contemporary phlebotomy practices for critically ill adults. METHODS: This is an observational cohort study of adults ≥18 years of age requiring intensive care unit (ICU) admission between January 1, 2019, and December 31, 2019, at a large academic medical center. Descriptive statistics were utilized to summarize all phlebotomy episodes throughout hospitalization, with each phlebotomy episode defined by unique peripheral venous, central venous, or arterial accesses for laboratory draws, exclusive of finger sticks. Secondarily, financial costs of phlebotomy and the relationships between phlebotomy practices, hemoglobin concentrations, and red blood cell (RBC) transfusions were evaluated. RESULTS: A total of 6194 patients were included: 59% were men with a median (interquartile range) age of 66 (54-76) years and median ICU and hospital durations of 2.1 (1.4-3.9) and 7.1 (4.3-11.8) days, respectively. The median number of unique laboratory draws was 41 (18-88) throughout hospitalization, with a median volume of 232 (121-442) mL, corresponding to 5.2 (2.6-8.8) draws and 29 (19-43) mL per day. Waste (ie, discard) volume was responsible for 10.8% of total phlebotomy volume. Surgical patients had a higher number of phlebotomy episodes and greater total phlebotomy volumes compared to nonsurgical patients. Phlebotomy practices differed across ICU types, with the greatest frequency of laboratory draws in the cardiac surgical ICU and the greatest daily phlebotomy volume in the medical ICU. Across hospitalization, ICU environments had the greatest frequency and volumes of laboratory draws, with the least intensive phlebotomy practice observed in the general hospital wards. Patients in the highest quartile of cumulative blood drawn experienced the longest hospitalizations, lowest nadir hemoglobin concentrations, and greatest RBC transfusion utilization. Differences in phlebotomy practice were limited across patient age, gender, and race. Hemoglobin concentrations declined during hospitalization, congruent with intensity of phlebotomy practice. Each 100 mL of phlebotomy volume during hospitalization was associated with a 1.15 (95% confidence interval [CI], 1.14-1.17; P < .001) multiplicative increase in RBC units transfused in adjusted analyses. Estimated annual phlebotomy costs exceeded $15 million (approximately $2500 per patient admission). CONCLUSIONS: Phlebotomy continues to be a major source of blood loss in hospitalized patients with critical illness, and more intensive phlebotomy practices are associated with lower hemoglobin concentrations and greater transfusion utilization.

Refining interpretation of transcutaneous bilirubin measurement in newborns born late preterm.

BACKGROUND: Transcutaneous bilirubin (TCB) monitoring is widely used for jaundice screening in the newborn period. Limited data exists on adjusting TCB for bias in late preterm infants. The objective of this study was to determine the median bias between transcutaneous bilirubin and total serum bilirubin levels in newborns born at 35-36 weeks' gestation. METHODS: This was a retrospective cohort study of late preterm infants born at 35-0/7 to 36-6/7 weeks' gestation who were admitted to a level III neonatal intensive care unit from May 2018 to February 2020. Transcutaneous and total serum bilirubin levels were assessed within 2 h of each other during the first 60 h of life. Bland-Altman plots were used to evaluate transcutaneous bilirubin bias. Bilirubin risk stratification based on age (in hours) was done using an adaptation of the Bhutani nomogram for transcutaneous, adjusted transcutaneous, and total serum bilirubin measurements. RESULTS: The median bias between transcutaneous and total serum bilirubin bias was 2.4 mg/dL (IQR 1.7-3.4, 95% CI 2.2-2.7). The kappa statistic demonstrated slight agreement between the unadjusted transcutaneous bilirubin and total serum bilirubin (k = 0.033, p = 0.194. The kappa statistic demonstrated fair agreement between an adjusted transcutaneous bilirubin (subtract 1 mg/dL) and total serum bilirubin (k = 0.298, p < 0.0001) and moderate agreement between another adjusted transcutaneous bilirubin (subtract 2 mg/dL) and total serum bilirubin (k = 0.430, p < 0.0001). CONCLUSION: In a single center study of late preterm infants, transcutaneous bilirubin systematically overestimated the total serum bilirubin level. Subtracting 1 mg/dL from the transcutaneous bilirubin identified infants with total serum bilirubin levels in the high or high intermediate risk range. Adjusting the transcutaneous bilirubin prior to risk stratification may reduce unnecessary blood draws for total serum bilirubin. Studies of racially and ethnically diverse newborns using various transcutaneous bilirubin meters are needed prior to broad application of the adjusted transcutaneous bilirubin approach.

Professional Certification in Point-of-Care Testing.

Professional certification is affirmation and documentation that the certified individual has the knowledge, training, and skills necessary to practice some aspect of medicine or other profession. Herein is a description of the genesis of a professional certification in point of care testing (POCT), inclusive of rationale and goals. A distinction between professional certification and certificate training programs is made. Details regarding eligibility to sit for the board exam are provided along with a list exam content areas. Finally, successes of this professional certification program are highlighted.

Analytical and Clinical Considerations in Implementing the Roche Elecsys Troponin T Gen 5 STAT Assay.

OBJECTIVES: To evaluate the analytical and clinical performance characteristics of the fifth-generation troponin T reagent. METHODS: Troponin T was measured in 2,332 paired serum and plasma samples from emergency department and hospital patients using the fourth- and fifth-generation reagents. Testing was repeated after recentrifugation to determine the frequency of analytical outliers and percentage of patients with elevated values for each assay. We conducted separate experiments to determine the effects of biotin and hemolysis interference, as well as measure interinstrument variability, for fifth-generation troponin T. RESULTS: Analytic outliers occurred more frequently using the fifth-generation reagent (3.4%) compared with the fourth-generation reagent (1.0%). The frequency of elevated troponin T above the 99th percentile upper reference limit was 26% for the fourth-generation reagent and 52% for the fifth-generation reagent. Clinically significant assay interference by biotin was observed at 20 ng/mL, but hemolysis interference was not observed until an H index of 150. Instrument-to-instrument variability between e411 and e601/602 instrument platforms is predicted to confound clinical interpretation of troponin changes. CONCLUSIONS: Analytical outliers and instrument-to-instrument variability are the two analytical variables most likely to confound interpretation of changes in fifth-generation troponin T results over time.

Analytical Sensitivity and Specificity of Four Point of Care Rapid Antigen Diagnostic Tests for SARS-CoV-2 Using Real-Time Quantitative PCR, Quantitative Droplet Digital PCR, and a Mass Spectrometric Antigen Assay as Comparator Methods.

BACKGROUND: We evaluated the analytical sensitivity and specificity of 4 rapid antigen diagnostic tests (Ag RDTs) for severe acute respiratory syndrome coronavirus 2, using reverse transcription quantitative PCR (RT-qPCR) as the reference method and further characterizing samples using droplet digital quantitative PCR (ddPCR) and a mass spectrometric antigen test. METHODS: Three hundred fifty (150 negative and 200 RT-qPCR positive) residual PBS samples were tested for antigen using the BD Veritor lateral flow (LF), ACON LF, ACON fluorescence immunoassay (FIA), and LumiraDx FIA. ddPCR was performed on RT-qPCR-positive samples to quantitate the viral load in copies/mL applied to each Ag RDT. Mass spectrometric antigen testing was performed on PBS samples to obtain a set of RT-qPCR-positive, antigen-positive samples for further analysis. RESULTS: All Ag RDTs had nearly 100% specificity compared to RT-qPCR. Overall analytical sensitivity varied from 66.5% to 88.3%. All methods detected antigen in samples with viral load >1 500 000 copies/mL RNA, and detected ≥75% of samples with viral load of 500 000 to 1 500 000 copies/mL. The BD Veritor LF detected only 25% of samples with viral load between 50 000 to 500 000 copies/mL, compared to 75% for the ACON LF device and >80% for LumiraDx and ACON FIA. The ACON FIA detected significantly more samples with viral load <50 000 copies/mL compared to the BD Veritor. Among samples with detectable antigen and viral load <50 000 copies/mL, sensitivity of the Ag RDT varied between 13.0% (BD Veritor) and 78.3% (ACON FIA). CONCLUSIONS: Ag RDTs differ significantly in analytical sensitivity, particularly at viral load <500 000 copies/mL.

The Elevated High-Sensitivity Cardiac Troponin T Pilot: Diagnoses and Outcomes.

OBJECTIVE: To identify the diagnoses and outcomes associated with elevated high sensitivity cardiac troponin T (hs-cTnT) compared with the 4th-generation troponin T and to validate the Mayo Clinic hs-cTnT myocardial infarction algorithm cutoff values. PATIENTS AND METHODS: Consecutive blood samples of patients presenting to the emergency department between July 2017 and August 2017, who had 4th-generation troponin T, were also analyzed using the hs-cTnT assay. Troponin T values, discharge diagnoses, comorbidities, and outcomes were assessed. In addition, analyses of sex-specific and hs-cTnT cutoff values were assessed. RESULTS: Of 830 patients, 32% had an elevated 4th-generation troponin T, whereas 64% had elevated hs-cTnT. With serial sampling, 4th-generation troponin missed a chronic myocardial injury pattern and acute myocardial injury pattern in 64% and 16% of patients identified with hs-cTnT, respectively. Many of these "missed" patients had discharge diagnoses associated with cardiovascular disease, infection, or were postoperative. Five of the 6 patients with unstable angina ruled in for myocardial infarction. CONCLUSION: There were many increases in hs-cTnT that were missed by the 4th-generation cTnT assay. Most new increases are not related to acute cardiac causes. They were more consistent with chronic myocardial injury. High-sensitivity cTnT did reclassify most patients with unstable angina as having non-ST-elevation myocardial infarction. Older age, more comorbidities, and lower hemoglobin were associated with elevated hs-cTnT. Our data also support the use of our sex-specific cutoff values.

Evaluation of the Cue Health point-of-care COVID-19 (SARS-CoV-2 nucleic acid amplification) test at a community drive through collection center.

Point-of-care (POC) tests are in high demand in order to facilitate rapid care decisions for patients suspected of SARS-CoV-2. We conducted a clinical validation study of the Cue Health POC nucleic acid amplification test (NAAT) using the Cue lower nasal swab, compared to a reference NAAT using standard nasopharyngeal swab, in 292 symptomatic and asymptomatic outpatients for SARS-CoV-2 detection in a community drive through collection setting. Positive percent agreement between Cue COVID-19 and reference SARS-CoV-2 test was 91.7% (22 of 24); or 95.7% (22 of 23) when one patient with no tie-breaker method was excluded. Negative percent agreement was 98.4% (239 of 243), and there were 25 (8.6%) invalid or canceled results. The Cue COVID-19 test demonstrated very good positive and negative percent agreement with central laboratory tests and will be useful in settings where accurate POC testing is needed to facilitate management of patients suspected of COVID-19.

Test Utilization Proposal for Reflex Bilirubin Testing: Why Order Two Tests When One Will Do?

BACKGROUND: Reflex testing algorithms are effective tools to reduce unnecessary laboratory testing. Direct (conjugated) bilirubin (DB) and total bilirubin (TB) are often ordered together at our institution. Therefore, the objective of our study was to evaluate the potential impact of performing reflex testing for DB when TB is elevated. METHODS: We performed a retrospective review of test orders (patients ≥18 years of age) for DB, TB, or for both DB and TB on the same accession number received in our stat laboratory from January through April 2017. The orders were binned into 4 categories depending on the results from each individual test: (a) DB normal and TB normal, (b) DB normal and TB high, (c) DB high and TB normal, and (d) DB high and TB high. The percentage of orders and median (range) test result for each category was calculated. RESULTS: During the months evaluated, a total of 4828 stat orders were placed for DB, TB, or both DB and TB. A total of 4296 stat orders (89%) were placed with both DB and TB on the same accession number for 4158 unique patients. Of those orders, the vast majority of tests (87.3%) contained normal results for both analytes; only 12.7% of orders contained ≥1 abnormal result. CONCLUSIONS: The majority of all bilirubin tests ordered stat for emergency department and hospitalized patients have values within the reference interval. Consequently, if reflex testing were executed on elevated TB, a large number of DB tests could be avoided.

Error simulation modeling to assess the effects of bias and precision on bilirubin measurements used to screen for neonatal hyperbilirubinemia.

OBJECTIVES: Error simulation models have been used to understand the relationship between analytical performance and clinical outcomes. We developed an error simulation model to understand the effects of method bias and precision on misclassification rate for neonatal hyperbilirubinemia using an age-adjusted risk assessment tool. METHODS: For each of 176 measured total bilirubin (TSBM) values, 10,000 simulated total bilirubin (TBS) values were generated at each combination of bias and precision conditions for coefficient of variation (CV) between 1 and 15%, and for biases between -51.3 µmol/L and 51.3 µmol/L (-3 and 3 mg/dL) fixed bias. TBS values were analyzed to determine if they were in the same risk zone as the TSBM value. We then calculated sensitivity and specificity for prediction of ≥75th percentile for postnatal age values as a function of assay bias and precision, and determined the rate of critical errors (≥95th percentile for age TSBM with <75th percentile TBS). RESULTS: A sensitivity >95% for predicting ≥75th percentile bilirubin values was observed when there is a positive fixed bias of greater than 17.1 µmol/L (1.0 mg/dL) and CV is maintained ≤10%. A specificity >70% for predicting <75th percentile bilirubin values was observed when positive systematic bias was 17.1 µmol/L (1 mg/dL) or less at CV ≤ 10%. Critical errors did not occur with a frequency >0.2% until negative bias was -17.1 µmol/L (-1 mg/dL) or lower. CONCLUSIONS: A positive systematic bias of 17.1 µmol/L (1 mg/dL) may be optimal for balancing sensitivity and specificity for predicting ≥75th percentile TSB values. Negative systematic bias should be avoided to allow detection of high risk infants and avoid critical classification errors.

Evaluation of the genalyte maverick SARS-CoV-2 multi-antigen serology panel.

Serologic testing for SARS-CoV-2 can be used for evaluation of past infection in individual patients and for community seroprevalence studies. We evaluated the analytical and clinical performance of the Genalyte Maverick SARS-CoV-2 Multi-Antigen Serology Panel compared to the Roche Elecsys Anti-SARS-CoV-2 nucleocapsid (NC) qualitative immunoassay, using well characterized clinical serum samples. A total of 143 pre-pandemic sera and 48 sera collected from patients with a negative molecular SARS-CoV-2 result were used for specificity studies. For sensitivity analyses, 179 sera were used, obtained 3-7 days, 8-14 days, or ≥ 15 days after symptom onset from patients with confirmed SARS-CoV-2 infection. Specificity was determined to be 95.3% (182/191) for the Genalyte Maverick. Overall sensitivity of the Genalyte Maverick was similar to that observed for the Roche Elecsys NC test, 79.3% (142/179) vs. 76.5% (137/179), respectively. Genalyte Maverick trended, without statistical significance, towards higher sensitivity as compared to the Roche Elecsys NC test in the 3-7 days (11/25 vs. 9/25, respectively) and 8-14 days (21/28 vs. 19/28, respectively) post-symptom onset sample sets, but was identical in the ≥ 15 days post-symptom onset group (106/116 vs. 106/116, respectively). Therefore, the Genalyte Maverick serologic test had similar overall sensitivity to the Roche Elecsys NC assay, but may have slightly improved sensitivity for early seroconversion. The lower Genalyte Maverick specificity as compared to the Roche Elecsys NC assay as reported by other studies (>99%), may necessitate confirmatory testing of positive Genalyte Maverick results if implemented for clinical use.