Kinetics of CMV seroconversion in a Swiss pregnant women population.

Retrospective evaluation of the kinetics of cytomegalovirus (CMV) seroconversion with CMV IgM, IgG, and IgG avidity assays, in a Swiss pregnant women population, has shown that the current published CMV serologic diagnostic algorithms were valid and fit for use. In 19% of the cases analyzed, CMV-specific IgM was detected before IgG.

The need for standardization of tacrolimus assays.

Background: Owing to the lack of an internationally recognized tacrolimus reference material and reference method, current LC-MS and immunoassay test methods used to monitor tacrolimus concentrations in whole blood are not standardized. The aim of this study was to assess the need for tacrolimus assay standardization.

Methods: We sent a blinded 40-member whole-blood tacrolimus proficiency panel (0-30 μg/L) to 22 clinical laboratories in 14 countries to be tested by the following assays: Abbott ARCHITECT (n = 17), LC-MS (n = 9), and Siemens Dade Dimension (n = 5).

Multisite analytical evaluation of the Abbott ARCHITECT cyclosporine assay.

The objective of this study was to evaluate the analytical performance of the Abbott ARCHITECT Cyclosporine (CsA) immunoassay in 7 clinical laboratories in comparison to liquid chromatography/tandem mass spectrometry (LC/MS/MS), Abbott TDx, Cobas Integra 800, and the Dade Dimension Xpand immunoassay. The ARCHITECT assay uses a whole blood specimen, a pretreatment step with organic reagents to precipitate proteins and extract the drug, followed by a 2-step automated immunoassay with magnetic microparticles coated with anti-CsA antibody and an acridinium-CsA tracer. Imprecision testing at the 7 evaluation sites gave a range of total % coefficient of variations of 7.

Multi-site analytical evaluation of a chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the Abbott ARCHITECT analyzer.

Objective: This study evaluated a new chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the ARCHITECT analyzer.

Design And Methods: Patient and laboratory proficiency samples were tested at three European sites and one site in the United States.

Results: The CMIA total %CV's were all <8% and the Limit of Quantification (LOQ) was <1.

Multi-site analytical evaluation of the Abbott ARCHITECT tacrolimus assay.

The objective of this study was to evaluate the analytical performance of the Abbott ARCHITECT Tacrolimus immunoassay. Proficiency panels and specimens from a population of organ transplant recipients were analyzed in 6 clinical laboratories in Europe and the United States, and the results were compared with other methods. The ARCHITECT assay requires a whole blood specimen pretreatment step with methanol/zinc sulfate to precipitate protein and extract the drug, followed by a 30-minute immunoassay using anti-tacrolimus antibody-coated paramagnetic microparticles and an acridinium-tacrolimus tracer.

Development of fully automated determination of marker-specific immunoglobulin G (IgG) avidity based on the avidity competition assay format: application for Abbott Architect cytomegalovirus and Toxo IgG Avidity assays.

Determination of the avidity of immunoglobulin G (IgG) directed against a specific marker has become an established diagnostic tool for identifying or excluding acute infections with pathogens. A novel assay format termed AVIcomp (avidity competition based on mass action) circumventing the conventional chaotropic format has been developed for determination of the avidity of marker-specific IgG in patient specimens. Its applications for cytomegalovirus (CMV) and Toxoplasma gondii are presented.

Validation of an automated immunoglobulin G-only cytomegalovirus (CMV) antibody screening assay and an assessment of the risk of transfusion transmitted CMV from seronegative blood.

Background: Cytomegalovirus (CMV) antibody donor screening assays have predominantly included both immunoglobulin G (IgG) and immunoglobulin M (IgM) detection. However, since in the majority of cases both CMV IgG and IgM are detected concomitantly during early seroconversion, CMV assays based only on IgG are now widely applied for donor screening.

Study Design And Methods: The performance of an automated microparticle CMV IgG assay (Abbott AxSYM CMV IgG microparticle enzyme immunoassay [MEIA]) was compared with an established total antibody blood screening assay (Abbott CMV Total AB EIA).