Performance evaluation of the Abbott Alinity Hepatitis C antigen next assay in a US urban emergency department population.

Introduction: HCV antibody assays have been used to screen for HCV, but confirmation of acute infection is dependent on RNA or core antigen testing. The aim of the study was to compare the performance of five HCV test methods, including RNA testing, on a US emergency department population.

Methods: Clinical performance metrics were calculated on 708 consenting Johns Hopkins Emergency Department patients who self-reported an increased risk for HCV infection.

Kinetics of SARS-CoV-2 Serum Antibodies Through the Alpha, Delta, and Omicron Surges Among Vaccinated Health Care Workers at a Boston Hospital.

Background: Longitudinal serology studies can assist in analyzing the kinetics of antibodies to SARS-CoV-2, helping to inform public health decision making. Our study aims to characterize circulating antibody trends over 18 months in vaccinated participants with and without evidence of COVID-19 infection.

Methods: A cohort of health care workers employed at Boston Medical Center was followed to collect serum samples and survey data over 6 time points from July 2020 through December 2021 (N = 527).

Reduced Serological Response to COVID-19 Booster Vaccine is Associated with Reduced B Cell Memory in Patients With Inflammatory Bowel Disease; VARIATION [VAriability in Response in IBD AgainsT SARS-COV-2 ImmunisatiON].

Background And Aims: Patients with inflammatory bowel disease [IBD] have an attenuated response to initial COVID-19 vaccination. We sought to characterize the impact of IBD and its treatment on responses after the third vaccine against SARS-CoV-2.

Methods: This was a prospective multicentre observational study of patients with IBD [n = 202] and healthy controls [HC, n = 92].

Pre-analytical considerations in the development of a prototype SARS-CoV-2 antigen ARCHITECT automated immunoassay.

Objectives: To evaluate pre-analytical challenges related to high-volume central laboratory SARS-CoV-2 antigen testing with a prototype qualitative SARS-CoV-2 antigen immunoassay run on the automated Abbott ARCHITECT instrument.

Methods: Contrived positive and negative specimens and de-identified nasal and nasopharyngeal specimens in transport media were used to evaluate specimen and reagent on-board stability, assay analytical performance and interference, and clinical performance.

Results: TCID50/mL values were similar for specimens in various transport media.

SARS-CoV-2 Anti-Spike IgG Antibody and ACE2 Receptor Binding Inhibition Levels among Breakthrough Stage Veteran Patients.

SARS-CoV-2 mRNA vaccines have been critical to curbing pandemic COVID-19; however, a major shortcoming has been the inability to assess levels of protection after vaccination. This study assessed serologic status of breakthrough infections in vaccinated patients at a Veterans Administration medical center from June through December 2021 during a SARS-CoV-2 delta variant wave. Breakthrough occurred mostly beyond 150 days after two-dose vaccination with a mean of 239 days.

Specificity and Confirmation of SARS-CoV-2 Serological Test Methods in Emergency Department Populations across the United States.

Background: Serological testing for SARS-CoV-2 is integral for understanding prevalence of disease, tracking of infections, confirming humoral response to vaccines, and determining timing and efficacy of boosters. The study objective was to compare the specificity of serology assays in emergency department populations across the United States in 2019 (pre-pandemic) and early 2020, incorporating an automated confirmatory assay.

Methods: Patient specimens (n = 1954) were from 4 regions in the United States: New York, NY; Milwaukee, WI; Miami, FL; and Los Angeles, CA.

Specificity and Confirmation of SARS-CoV-2 Serological Test Methods in Emergency Department Populations Across the United States in 2019 and Early 2020.

Background: Serological testing for SARS-CoV-2 is integral for understanding prevalence of disease, tracking of infections, confirming humoral response to vaccines, and determining timing and efficacy of boosters. The study objective was to compare the specificity of serology assays in emergency department populations across the United States in 2019 (pre-pandemic) early 2020 incorporating an automated confirmatory assay.

Methods: Patient specimens (n = 1954) were from four regions in the United States: New York, NY; Milwaukee, WI; Miami, FL; and Los Angeles, CA.

Reduced Serological Response to COVID-19 Vaccines in Patients with IBD is Further Diminished by TNF Inhibitor Therapy; Early Results of the VARIATION study [VAriability in Response in IBD Against SARS-COV-2 ImmunisatiON].

Background And Aims: Evidence suggests patients with inflammatory bowel disease [IBD] receiving TNF antagonists have attenuated response to vaccination against COVID-19. We sought to determine the impact of IBD and of various medications for treatment of IBD on antibody responses to vaccination against COVID-19.

Methods: Patients with IBD [n = 270] and healthy controls [HC, n = 116] were recruited prospectively, and quantitative antibody responses were assessed following COVID-19 vaccination.

Time-related performance characteristics of high-sensitivity troponin I assay using manufacturer's controls and reagents.

Background: Troponin is a widely used cardiac protein biomarker for acute coronary syndrome. Its increasing importance drives an increasing need to assess, in real-world conditions, the performance of the tests to measure it. We evaluated the performance characteristics of high-sensitivity troponin I assay reagents and ancillary agents on the Abbott ARCHITECT ci4100, ARCHITECT i2000SR and Alinity ci using historical quality control data spanning 5 years.

Anti-SARS-CoV-2 IgM improves clinical sensitivity early in disease course.

Introduction: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is diagnosed by molecular-based detection of SARS-CoV-2 RNA. Serologic testing detects antibodies specific to SARS-CoV-2 and IgM specifically may serve as an adjunct test to PCR early in disease. We evaluated the Abbott anti-SARS-CoV-2 IgM and IgG assays along with DiaSorin anti-SARS-CoV-2 IgG and Roche anti-SARS-CoV-2 Total.

Performance characteristics of the high sensitivity Alinity i & ARCHITECT HBsAg Next Qualitative/Confirmatory assays.

Despite improvement in vaccinations, Hepatitis B remains a major health concern due to the difficulty of prevention even in low endemic areas such as Europe. In this report we describe the performance characteristics of the new HBsAg Next Qualitative and HBsAg Next Confirmatory assays designed for blood screening and diagnostic purposes on the Alinity i and ARCHITECT fully automated systems. The new assays were evaluated in comparison to the ARCHITECT HBsAg Qualitative II and Confirmatory assays on seroconversion, analytical sensitivity, and mutant panels along with testing of over 400 clinical positive samples demonstrating excellent improvements in sensitivity.

A novel Sigma metric encompasses global multi-site performance of 18 assays on the Abbott Alinity system.

Objectives: The Abbott Alinity family of chemistry and immunoassay systems recently launched with early adopters contributing imprecision and bias data, which was consolidated to assess the performance of Alinity assays across multiple sites using the Sigma metric. Multi-site Sigma metrics were determined for 3 ion-selective electrodes, 12 photometric assays, and 3 immunoassays across 11 independent laboratory sites in 9 countries.

Methods: Total allowable error (TEa) goals followed a previously defined hierarchy that used CLIA as the primary goal.

Evaluation of the sensitivity and specificity of six HIV combined p24 antigen and antibody assays.

In this study, we evaluated the performance of six HIV combined p24 antigen and antibody (Ag/Ab) assays versus two third-generation anti-HIV antibody assays. The assays were evaluated using p24 antigen panel of 31 HIV-1 subtypes (n = 124), 25 HIV-1 seroconversion panels (n = 176), HIV-1 antibody positive samples including group M subtypes and group O (n = 559), HIV-2 positive samples (n = 110), and unselected HIV negative samples from four French private laboratories (n = 1005). The results showed that overall HIV combined Ag/Ab assays present better performance, when compared to antibody-only assays.

Multicenter evaluation of a new, automated enzyme-linked immunoassay for detection of human immunodeficiency virus-specific antibodies and antigen.

A collaborative multicenter study was conducted to evaluate the sensitivity, specificity, and precision of a three-step, fully automated, qualitative microparticle-based enzyme-linked immunoassay (AxSYM HIV Ag/Ab Combo; Abbott Laboratories), designed to simultaneously detect (i). antibodies against human immunodeficiency virus type 1 (HIV-1) and/or type 2 (HIV-2) and (ii). HIV p24 antigen.