Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING LLC
FOCUS DIAGNOSTICS, INC.
RANDOX LABORATORIES

Effective Way to Diagnose Latent Tuberculosis Identified

By Labmedica International staff writers
Posted on 05 Jun 2014
Image: The QuantiFERON-TB Gold In-Tube whole blood enzyme-linked immunosorbent assay (ELISA) for the diagnosis of tuberculosis (Photo courtesy of Cellestis).
Image: The QuantiFERON-TB Gold In-Tube whole blood enzyme-linked immunosorbent assay (ELISA) for the diagnosis of tuberculosis (Photo courtesy of Cellestis).
The effective control and elimination of tuberculosis (TB) in low-incidence countries requires the prompt identification of individuals with active and latent TB infection (LTBI).

The diagnosis of latent TB is important because the bacterium can persist in the body only to emerge and reactivate months or even years later. Therefore treating individuals with latent TB can prevent disease developing and so prevent them infecting others.

Scientists at University of Birmingham (Edgbaston, UK) working with colleagues from other British institutes performed a prospective, longitudinal cohort study among 166 Nepalese military recruits who had left Nepal and recently entered the UK. The study was carried out from February to September 2012, and assessed longitudinal interferon (IFN)-gamma release assays (IGRA) and tuberculin skin test (TST) responses. They also studied the influence of antecedent TST and LTBI treatment on IGRA performance.

Two commercially available assays were used. The QuantiFERON-TB Gold In-Tube (QFT-GIT; Cellestis; Carnegie, Australia) a whole blood enzyme-linked immunosorbent assay (ELISA), and the T-SPOT.TB assay (Oxford Immunotec; Abingdon, UK) enzyme-linked immunospot (ELISPOT) assay using peripheral blood mononuclear cells (PBMCs). On the day following blood sampling for the IGRAs, a TST was performed by the Mantoux method.

The IGRA testing revealed that 21 individuals were T-SPOT.TB positive (12.9%, with two who were borderline positive, and eight were QFT-GIT positive (4.8%). All QFT-GIT positives were also T-SPOT.TB positive. Thus, 61.9% T-SPOT.TB positive participants were QFT-GIT negative, meaning the tests showed moderate agreement.

Adam F. Cunningham, PhD, the senior author of the study and a professor of Functional Immunity, said, “One of the problems with latent TB is that it is very tricky to diagnose. We have found this test is the best way for diagnosing latent TB in this group. What we found was that one IGRA was more effective at identifying latent TB infected individuals than the other tests. This commercially-produced test, called T-Spot, is a blood test that measures T cells specific to certain Mycobacterium tuberculosis antigens. It is cost-effective because individuals only require one visit to be tested.” The study was published on May 9, 2014, in the journal Public Library of Science ONE.

Related Links:

University of Birmingham
Cellestis 
Oxford Immunotec 



KARL HECHT GMBH & CO KG
CELLAVISION AB
MEDLAB Asia

Channels

Genetic Tests

view channel
Image: For each chromosome, key SNPs are displayed above the chromosome and non-key SNPs below the chromosome, enabling users to determine the accuracy of haploblock calling. SNPs failed to be called are displayed as white points in the middle of the chromosome (Photo courtesy of Illumina).

Karyomapping Proposed as Alternative to Preimplantation Genetic Diagnosis for Evaluation of IVF Embryos

British researchers have suggested that karyomapping is a viable and cost-effective method for detecting a wide range of genetic diseases in IVF (in vitro fertilization) embryos. Preimplantation Genetic... Read more

Industry News

view channel
Image: Positive case of lung tissue stained for ALK with VENTANA ALK (D5F3) CDx Assay, a companion diagnostic immunohistochemical test in the final stages of the FDA premarket approval process (Photo courtesy of Ventana Medical Systems and PRNewsFoto).

Premarket Approval Sought for CDx Test to Benefit Lung Cancer Patients

Ventana Medical Systems, Inc. (Tucson, AZ, USA) has announced its US Food & Drug Administration (FDA) final stage submission for premarket approval (PMA) of its companion diagnostic (CDx) immunohistochemistry... Read more
 

Events

05 Mar 2015 - 08 Mar 2015
18 Mar 2015 - 20 Mar 2015
Copyright © 2000-2015 Globetech Media. All rights reserved.