Clin Chem Lab Med
September 2022
Objectives: Rheumatoid factor (RF) is a well-established marker for the diagnosis and classification of rheumatoid arthritis (RA). Most studies evaluated IgM RF or isotype-nonspecific total RF assays. We evaluated the added value of IgA RF in this context.
View Article and Find Full Text PDFIntroduction: Commercial assays measuring antibodies to citrullinated protein/peptide (ACPA) show poor quantitative agreement. The diagnostic industry has never adopted the International Union of Immunological Societies-Centers for Disease Control and Prevention (IUIS-CDC) ACPA reference standard. Recently, the National Institute for Biological Standards and Control (NIBSC) prepared a new candidate ACPA standard (18/204).
View Article and Find Full Text PDFBackground: Calprotectin (CLP) is a promising biomarker for the evaluation of neutrophil-related inflammation. Our aim was to establish reference values for circulating CLP in different sample types and to study the effect of pre-analytical variables.
Methods: Reference values were determined in 100 healthy individuals.
Objectives: Currently available computer-aided diagnosis (CAD) systems for the detection of anti-nuclear antibodies (ANA) by indirect immunofluorescence (IIF) assay enable a standardized measurement of system-specific fluorescent intensity (FI) measures. We aimed to evaluate an internal quality control (iQC) program that controls the total ANA IIF process in routine practice.
Methods: In addition to the kit iQC materials, supplemental quality indicators were integrated in a total quality assurance (QA) program: patient-derived iQC's samples (negative, 1/160 fine speckled and 1/160 homogeneous), median sample FI per run and percentage of ANA IIF positive samples per run.
Background There is a need for additional biomarkers to assist in the diagnosis and prognosis of rheumatoid arthritis (RA). The aim of our study was to evaluate the (pre-analytical, analytical and clinical) performance of serum calprotectin as a marker of inflammation in RA. Methods The study population included 463 rheumatologic patients (including 111 RA patients and 352 controls) who for the first time consulted a rheumatologist, 20 healthy controls and 27 patients with an infectious disease.
View Article and Find Full Text PDFBackground The introduction of automated anti-nuclear antibody (ANA) indirect immunofluorescence (IIF) analysis may allow for more harmonized ANA IIF reporting, provided that a thorough quality assurance program controls this process. The aim of this study was to evaluate various quality indicators used for ANA IIF analysis with the final goal of optimizing the iQC program. Methods In an experimental setup, we introduced artificial errors, mimicking plausible problems during routine practice on a QUANTA-Lyser-NOVA View® system (Inova Diagnostics, San Diego, CA, USA).
View Article and Find Full Text PDFObjectives: Rheumatoid factor (RF) and anti-cyclic citrullinated protein/peptide antibodies (ACPA) are integrated in the 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for rheumatoid arthritis (RA). The objectives of this study were to evaluate the technical and diagnostic performance of different RF and ACPA assays and to evaluate whether differences in performance impact RA classification.
Methods: Samples from 594 consecutive patients who for the first time consulted a rheumatologist (44 of whom were diagnosed with RA) and 26 extra newly diagnosed patients with RA were analysed with six different RF assays (Menarini, Thermo Fisher, Inova, Roche, Abbott, Euroimmun) and seven different ACPA assays (Menarini, Thermo Fisher, Inova, Roche, Abbott, Euro Diagnostica, Euroimmun).
. Our study aimed to investigate whether the introduction of automated anti-nuclear antibody (ANA) indirect immunofluorescence (IIF) analysis decreases the interlaboratory variability of ANA titer results. .
View Article and Find Full Text PDFBackground: We evaluated the analytical performance of six different faecal calprotectin immunoassays together with their diagnostic accuracy in the discrimination between functional and organic bowel disorders.
Methods: The faecal samples were obtained from inflammatory bowel disease patients (n=27) at the time of diagnosis [Crohn's disease (n=15), colitis ulcerosa (n=12)], gastroenterologic disease control patients (n=52) and rheumatologic disease control patients (n=26). All individuals included in the study underwent a concurrent ileocolonoscopy.
Background: During the final phases of bioethanol fermentation, yeast cells face high ethanol concentrations. This stress results in slower or arrested fermentations and limits ethanol production. Novel Saccharomyces cerevisiae strains with superior ethanol tolerance may therefore allow increased yield and efficiency.
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