Distinguishing Daratumumab from Endogenous Monoclonal Proteins in Serum from Multiple Myeloma Patients Using an Automated Mass Spectrometry System.

Background: Therapeutic monoclonal antibodies (t-mAbs) may interfere with electrophoresis-based methods used to monitor multiple myeloma (MM), which can create inaccurate results. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is an alternative to gels distinguishing between endogenous M-proteins and t-mAbs based on molecular mass.

Methods: Serum samples (n = 109) from 34 MM patients receiving Dara-KRd were collected 14 or 28 days postdaratumumab administration.

Alinity hq platelet count is not impacted by severe microcytosis.

Background: Impedance technology has been shown to overestimate platelet (PLT) count in samples with microcytes, while the optical-fluorescence PLT count (PLT-F) by Sysmex has been suggested to be unaffected by microcytosis. The Abbott Alinity hq analyzer employs multi-dimensional optical PLT counting. Our goal was to assess the accuracy of this technology in microcytic samples.

Accurate white blood cell differential by Alinity hq: A comparison with flow cytometry and manual differential.

Introduction: White blood cell (WBC) differential by flow cytometry can report a six-part WBC differential and enumerate blasts. Some modern hematology analyzers are also able to provide a six-part WBC differential (including immature granulocytes). Our goal was to compare the WBC differential obtained by the Abbott Alinity hq hematology analyzer to an 8-color single-tube flow cytometry method and to manual WBC differential.

Clinical utility of Abbott Alinity hq extended red blood cell parameters in differentiating β-thalassemia trait and iron deficiency anemia.

Introduction: The objective of the study was to evaluate the performance of the Abbott Alinity hq advanced multi angle polarized scatter separation (MAPSS )-based optical RBC technology, for the differentiation between iron deficiency anemia (IDA) and β-thalassemia carrier status.

Methods: Four hundred and sixty-four samples were analyzed. 228 were healthy controls, 30 were β-thalassemia carriers, and 40 were IDA.

Alinity hq platelet results are equivalent with the international reference method in thrombocytopenic samples.

Introduction: Accurate and precise platelet (PLT) count is critical for the appropriate management of patients with thrombocytopenia. This study evaluated the performance of PLT counting with the Abbott Alinity hq hematology analyzer, which utilizes multi-dimensional optical technology.

Methods: Imprecision, linearity, and accuracy were assessed per CLSI guidelines.

Multicenter performance evaluation of the Abbott Alinity hq hematology analyzer.

Background Alinity hq (Abbott) is a new high-throughput hematology analyzer that exclusively employs optical principles for detecting and enumerating blood cells. It reports 29 parameters, including a six-part white blood cell (WBC) differential. The aim of this multicenter study was to evaluate the analytical and clinical performance of the Alinity hq.

Performance evaluation of the prototype Abbott Alinity hq hematology analyzer.

Introduction: The analytical and clinical performance as well as the workflow efficiency of the novel, prototype Alinity hq hematology analyzer was evaluated in the clinical laboratory of Universitair Ziekenhuis Brussel, Department of Hematology, Brussels, Belgium.

Methods: Within-run and within-laboratory imprecision, linearity, and carryover were assessed using clinical blood samples and commercial blood products. Four hundred and seventeen samples were selected for method comparison with Abbott CELL-DYN Sapphire, and for flagging performance analysis in comparison with smear review and manual microscopic white blood cell (WBC) differential.

A Clinical Approach for Defining the Threshold between Low and Medium Anti-Cardiolipin Antibody Levels for QUANTA Flash Assays.

The threshold between low and medium antibody levels for anticardiolipin (aCL) and anti-β2 glycoprotein I antibodies (aβ2GPI) for the diagnosis of antiphospholipid syndrome (APS) remains a matter of discussion. Our goal was to create a protocol for determining the low/medium antibody cut-off for aCL antibody methods based on a clinical approach, and utilize it to establish the clinically-relevant low/medium threshold for QUANTA Flash aCL chemiluminescent immunoassay (CIA) results. The study included 288 samples from patients with primary APS ( = 70), secondary APS ( = 42), suspected APS ( = 36), systemic lupus erythematosus (SLE) without APS ( = 96) and other connective tissue diseases ( = 44).

Clinical performance evaluation of a novel, automated chemiluminescent immunoassay, QUANTA Flash CTD Screen Plus.

The QUANTA Flash(®) CTD Screen Plus is a chemiluminescent immunoassay (CIA) for the detection of the major antinuclear antibodies (ANA) on the BIO-FLASH(®) platform. NOVA View(®) is an automated fluorescence microscope that acquires digital images of indirect immunofluorescent assay (IFA) slides. Our goal was to evaluate the clinical performance of the two automated systems and compare their performance to that of traditional IFA.

Anti-CarP antibodies as promising marker to measure joint damage and disease activity in patients with rheumatoid arthritis.

Anti-citrullinated protein antibodies (ACPA) are important serological markers in the diagnosis of rheumatoid arthritis (RA) and are part of the recent disease classification criteria. However, there is a strong need for reliable markers for measuring and predicting joint damage and disease activity. Recently, antibodies directed against carbamylated antigens (anti-CarP antibodies) were identified.

Clinical evaluation of a novel chemiluminescent immunoassay for the detection of anti-citrullinated peptide antibodies.

Background: We evaluated the analytical and clinical performances of a novel, automated chemiluminescent immunoassay in comparison with several anti-citrullinated protein antibody (ACPA) assays (2nd and 3rd generations) based on various platforms and technologies.

Methods: Samples from rheumatoid arthritis (RA) patients (n=141) and controls (n=153) were collected based on an ordered ACPA test. All samples were tested with QUANTA Flash® CCP3, QUANTA Lite® CCP3, QUANTA Lite® CCP3.

Anti-nuclear antibody screening using HEp-2 cells.

The American College of Rheumatology position statement on ANA testing stipulates the use of IIF as the gold standard method for ANA screening(1). Although IIF is an excellent screening test in expert hands, the technical difficulties of processing and reading IIF slides--such as the labor intensive slide processing, manual reading, the need for experienced, trained technologists and the use of dark room--make the IIF method difficult to fit in the workflow of modern, automated laboratories. The first and crucial step towards high quality ANA screening is careful slide processing.

Novel clinical and diagnostic aspects of antineutrophil cytoplasmic antibodies.

Antineutrophil cytoplasmic antibodies (ANCA) are the serological hallmark of some idiopathic systemic vasculitides. Besides the investigation of ANCA-associated vasculitis (AAV) and constant effort for a standardized nomenclature and classification of the AAV, a main focus of research during the last few years has been to constantly improve the performance of enzyme immunoassays. With the latest so called third generation ELISA, this goal seemed to be fulfilled.

14th International Congress on Antiphospholipid Antibodies Task Force. Report on antiphospholipid syndrome laboratory diagnostics and trends.

Current classification criteria for definite Antiphospholipid Syndrome (APS) require the use of three laboratory assays to detect antiphospholipid antibodies (aCL, anti-β2GPI and LA) in the presence of at least one of the two major clinical manifestations (i.e. thrombosis or pregnancy morbidity) of the syndrome.

Analytical and clinical comparison of two fully automated immunoassay systems for the diagnosis of celiac disease.

Objective: Here we compared analytical and clinical performance characteristics of two novel automated assay systems for the detection of celiac disease (CD) specific antibodies: QUANTA Flash (INOVA Diagnostics, Inc.) and EliA (Thermo Scientific).

Methods: A total of 74 biopsy-proven CD patients (2 with IgA deficiency) and 138 controls were tested by both methods.

Standardization of antiphospholipid antibody testing--historical perspectives and ongoing initiatives.

The measurement of antiphospholipid antibodies (aPL) has been an important aspect of antiphospholipid syndrome (APS) characterization since the disease was first described in the 1980s. Despite significant efforts geared toward the standardization of immunoassays that measure anticardiolipin antibodies and anti-β2-glycoprotein I spanning three decades, there are still reports of significant interassay and interlaboratory variation in the results of these assays. At the recent 13th International Congress on Antiphospholipid Antibodies (APLA 2010, April 13-16, 2010, Galveston, TX), a task force composed of internationally recognized experts in the field of APS was formed to address these issues.

Clinical performance evaluation of a novel rapid response chemiluminescent immunoassay for the detection of autoantibodies to extractable nuclear antigens.

Background: We analyzed the performance of a novel ENA screening chemiluminescent immunoassay (CIA) and the confirmation QUANTA Flash tests.

Methods: Sera (n=1079) from patients referred to a rheumatology clinic were screened by QUANTA Flash ENA7 (INOVA Diagnostics). All positive (n=89) and a matched control group (n=90) were reflexed for autoantibodies to the individual antigens.

Superior performance of the CCP3.1 test compared to CCP2 and MCV in the rheumatoid factor-negative RA population.

Anti-citrullinated protein/peptide antibodies (ACPAs) have recently been identified as sensitive and specific diagnostic and prognostic markers in rheumatoid arthritis (RA). In this study, we wished to assess the diagnostic performance of the third-generation anti-CCP3.1 assay, but with special focus on the rheumatoid factor (RF)-negative RA population.

Interference in antiphospholipid antibody assays.

Antiphospholipid antibodies (aPL) are detected with two types of laboratory tests: first, antigen-specific immunoassays for the determination of antibodies against cardiolipin, β2-glycoprotein I and other phospholipids, and phospholipid-protein complexes; second, functional (coagulation) assays for the detection of lupus anticoagulants. Both aPL immunoassays and coagulation assays are prone to interferences, and clinicians need to be aware of the limitations of these assays. Interference is a clinically significant bias in the measured analyte concentration due to the effect of another component or property of the sample.

Standards and reference materials for the anticardiolipin and anti-β2glycoprotein I assays: a report of recommendations from the APL Task Force at the 13th International Congress on Antiphospholipid Antibodies.

Background: The confirmation of diagnosis of the Antiphospholipid Syndrome (APS) relies on laboratory tests. Current classification criteria for definite APS mandate the use of three "standardized" laboratory assays to detect antiphospholipid antibodies (aPL) [viz: anticardiolipin (aCL) IgG and IgM, anti-β(2)glycoprotein I (anti-β(2)GPI) antibodies IgG and IgM and/or a lupus anticoagulant (LAC)], when at least one of the two major clinical manifestations (thrombosis or pregnancy losses) are present. Several attempts have been made to standardize the aCL and anti-β(2)GPI tests, though, a considerable degree of inconsistencies still exist, limiting the clinical and diagnostic value of aPL tests.