Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
RANDOX LABORATORIES

Newest Combination HIV Antigen-Antibody Assay Evaluated

By Labmedica International staff writers
Posted on 27 Feb 2013
Print article
Diagnostic tests capable of early detection represent the most effective means of preventing transmission of human immunodeficiency virus (HIV).

A fourth-generation antigen-antibody combination assay has been developed to allow earlier detection of seroconversion, and has increased sensitivity and improved specificity.

Scientists at the Innsbruck University Hospital (Austria) determined how early the assay could detect infection compared with existing assays; whether all HIV variants could be detected; and the assay's specificity using samples from blood donors, routine specimens, and patients with potential cross-reacting factors.

The study was carried out at 12 centers in Europe, Thailand, and Australia. The Elecsys HIV combi PT assay (Roche Diagnostics; Penzberg, Germany) is performed according to the sandwich principle. The results are automatically determined by the Elecsys software that compares the signal produced from the sample with the cutoff value obtained during system calibration. The total assay time is 27 minutes.

A total of 14 seroconversion panels, comprising 135 samples were analyzed to determine how soon after a positive polymerase chain reaction (PCR) result the immunoassays could detect HIV infection. Samples were identified as positive by the Elecsys assay 4.9 days after a positive PCR result that had been predetermined, which was earlier than the 5.3 to 7.1days observed with other comparable assays. The analytical sensitivity of the Elecsys HIV combi PT assay for the HIV-1 p24 antigen was 1.05 IU/mL, which compares favorably with the other assays.

In addition, the assay identified all screened HIV subtypes and displayed greater sensitivity to HIV-2 homologous antigen and antibodies to HIV-1 E and O and HIV-2 than the other assays. The assay demonstrated 100% specificity in patients with infections other than HIV, such as Cytomegalovirus or herpes simplex virus. Overall, the specificity of the Elecsys assay was 99.88% using samples from blood donors and 99.81% when analyzing unselected samples. Potential cross-reacting factors did not interfere with assay performance. The Elecsys HIV combi PT assay has been granted the European Conformity (CE) marking and is now available for use in laboratory-based testing. The study was published in the February 2013 issue of the journal Medical Microbiology and Immunology.

Related Links:
Innsbruck University Hospital
Roche Diagnostics


Print article

Channels

Clinical Chemistry

view channel
Image: Dried blood spots are used to screen newborns for a number of rare inherited conditions. A new dried blood spot screening test has been developed for Niemann-Pick type C, a rare neurodegenerative condition that usually is not diagnosed until after damage to brain cells has begun (Photo courtesy of Washington University School of Medicine).

Newborn Screening Test Developed For Deadly Neurological Disorder

A newborn screening test has been introduced that identifies infants with Niemann-Pick disease type C, an often fatal condition in which cholesterol builds up and eventually destroys brain cells.... Read more

Genetic Tests

view channel
Image: The BioMek FXP automation workstation (Photo courtesy of Beckman Coulter).

Innovative Gene Testing Technology Finds Cancer Risks

A new method has been developed for identifying mutations and prioritizing variants in breast and ovarian cancer genes, which will not only reduce the number of possible variants for doctors to investigate,... Read more

Pathology

view channel
Image: An IsoPSA test for prostate cancer detection and differentiation (Photo courtesy of Dr. Arnon Chait, PhD).

Novel Test Differentiates Malignant Prostate Cancer Grades

A promising new test has been introduced that detects prostate cancer more precisely than current tests, by identifying molecular changes in the prostate specific antigen (PSA) protein and can also differentiate... Read more

Industry News

view channel

R-Biopharm and Merck Partner on Companion Diagnostics

R-Biopharm AG (Darmstadt, Germany) and Merck KGaA (Darmstadt, Germany) have entered into an agreement that constitutes their first collaboration, which will initially focus on developing and launching companion diagnostics. Companion diagnostics play a central role in personalized medicine by helping to find specific... Read more
Copyright © 2000-2016 Globetech Media. All rights reserved.