We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress hp
Sign In
Advertise with Us
PURITAN MEDICAL

Download Mobile App




Interferon-Gamma Release Assays Preferred for Latent TB

By LabMedica International staff writers
Posted on 30 May 2012
Interferon-gamma release assays (IGRAs) are significantly better than tuberculin skin tests (TST) at predicting progression from latent tuberculosis (TB). More...


In order to avoid unnecessary treatment, mass therapy of latent TB infection depends above all on the availability and use of adequate screening tests that more accurately predict progression from latent tuberculosis infection (LTBI) to active tuberculosis than the TST does.

Scientists at the Medical School Hanover (Germany) carried out a meta-analysis to qualitatively evaluate the positive predictive value (PPV) and negative predictive value (NPV) for progression of commercial and “in-house” IGRAs and the TST for persons not receiving preventive treatment. The respective IGRA studies were pooled using both a fixed and a random effect model. In all, 1,225 subjects were tested by "in house" IGRAs, 5,194 by commercial IGRAs and 8,479 by TST.

The pooled PPV for progression for all studies using commercial IGRAs was 2.7%, which was statistically significant compared with 1.5% for the TST.

PPV increased to 6.8% for the IGRAs and 2.4% for the TST when only high-risk groups were considered. Pooled values of NPV for progression for both IGRAs and the TST were very high at 99.7% and 99.4%, although significantly higher for IGRAs.

Five studies included in the metaanalysis utilized “in-house” tests; seven used the T-SPOT.TB ELISPOT (Oxford Immunotec Ltd.; Abingdon, UK); four used the QuantiFERON-TB Gold (QFT-G) and 14 used its successor the QuantiFERON-TB Gold In-Tube (QFT-IT), both products of Cellestis Ltd., (Chadstone, Australia). QFT-IT uses whole blood and produces a result within 16 hours and T-SPOT processes peripheral blood mononuclear cells within eight hours measuring the number of interferon-gamma producing cells.

Roland Diel, MD, MPH, the lead authors of the study said, "This is also highly important for tuberculosis control programs, because a test with a high negative predictive value means that therapy for latent tuberculosis can be limited to test-positive contacts without the danger of overlooking some who are truly infected but undetected by the tests."

The authors concluded that progression rates for commercial IGRA blood tests are remarkably higher than those for the TST, but remain low in absolute numbers. The data suggests that IGRAs provide significant benefits over the TST, but that the use of IGRAs, and testing for LTBI in general, should be targeted at high-risk groups. The study was published online on April 5 2012 in the journal Chest.

Related Links:

Medical School Hanover
Oxford Immunotec Ltd.
Cellestis Ltd.



New
Gold Member
Quality Control Material
iPLEX Pro Exome QC Panel
3-Part Differential Hematology Analyzer
Swelab Alfa Plus Sampler
New
Gold Member
Serological Pipets
INTEGRA Serological Pipets
New
Gold Member
Blood Gas Analyzer
Stat Profile pHOx
Read the full article by registering today, it's FREE! It's Free!
Register now for FREE to LabMedica.com and get access to news and events that shape the world of Clinical Laboratory Medicine.
  • Free digital version edition of LabMedica International sent by email on regular basis
  • Free print version of LabMedica International magazine (available only outside USA and Canada).
  • Free and unlimited access to back issues of LabMedica International in digital format
  • Free LabMedica International Newsletter sent every week containing the latest news
  • Free breaking news sent via email
  • Free access to Events Calendar
  • Free access to LinkXpress new product services
  • REGISTRATION IS FREE AND EASY!
Click here to Register








DIASOURCE (A Biovendor Company)

Channels

Molecular Diagnostics

view channel
Image: The RNA-seq based diagnostic test for pediatric leukemia ensures better outcomes for children with this common cancer (Photo courtesy of Qlucore)

RNA-Seq Based Diagnostic Test Enhances Diagnostic Accuracy of Pediatric Leukemia

A new unique test is set to reshape the way Acute Lymphoblastic Leukemia (BCP-ALL) samples can be analyzed. Qlucore (Lund, Sweden) has launched the first CE-marked RNA-seq based diagnostic test for pediatric... Read more

Hematology

view channel
Image: CitoCBC is the world first cartridge-based CBC to be granted CLIA Waived status by FDA (Photo courtesy of CytoChip)

Disposable Cartridge-Based Test Delivers Rapid and Accurate CBC Results

Complete Blood Count (CBC) is one of the most commonly ordered lab tests, crucial for diagnosing diseases, monitoring therapies, and conducting routine health screenings. However, more than 90% of physician... Read more

Immunology

view channel
Image: A simple blood test could replace surgical biopsies for early detecion of heart transplant rejection (Photo courtesy of Shutterstock)

Blood Test Detects Organ Rejection in Heart Transplant Patients

Following a heart transplant, patients are required to undergo surgical biopsies so that physicians can assess the possibility of organ rejection. Rejection happens when the recipient’s immune system identifies... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.