Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New TB test means quicker and easier diagnosis for patients

10.03.2008
A new blood test could enable doctors to rule out tuberculosis (TB) infection within days rather than weeks, according to a new study published this week in the journal Annals of Internal Medicine.

The study, by researchers from Imperial College London and the University of Oxford, shows that doctors can determine that a patient does not have tuberculosis with 99% accuracy when using the new blood test, ELISpot-Plus, in conjunction with a skin test known as tuberculin skin testing, already in use.

TB is difficult to diagnose because many of its symptoms, such as fever, fatigue, and loss of appetite, are also commonly found in many other conditions. The combination of ELISpot-Plus and tuberculin skin testing is able to rule out TB within 48 hours, providing a much quicker result than existing testing methods, for which results take up to several weeks.

The new test combination could prevent patients who do not have TB from being subjected to further lengthy TB tests, and allow doctors to begin investigating other explanations for such patients' symptoms.

The new study showed that ELISpot-Plus alone was accurately able to determine TB infection in 89% of cases and tuberculin skin testing alone was able to determine TB infection in 79% of cases. However, using both tests together was able to rule out TB infection with an accuracy of 99%.

The ELISpot-Plus test works by detecting signs of a particular response that occurs when the immune system encounters TB infection. The test looks for a type of protein known as interferon-Y. This is secreted by T cells in the immune system when they encounter antigens found in the bacterium mycobacterium tuberculosis, which causes most cases of TB.

The tuberculin skin test commonly gives falsely positive results if a patient has previously been vaccinated against TB, because vaccination causes a reaction in the immune system which looks very similar to its reaction against actual TB infection. ELISpot-Plus is able to distinguish TB infection from BCG vaccination because it uses special antigens that only pick out the T cells that are induced by TB infection, and not those induced by vaccination.

The new test is useful in determining a patient's TB status but the results are not able to accurately reveal whether a patient with TB has it the 'active' form, which causes symptoms, or the dormant 'latent' form, which does not. This means that patients with a positive result would need further testing. However, the new test combination should allow doctors to establish which patients require further TB testing and which do not.

At present, the 'gold standard' for confirming whether or not a patient has TB involves growing cultures from sputum samples from a patient and analysing these cultures to see if they contain traces of mycobacterium tuberculosis.

This means that patients being tested for TB need to stay in hospital for three days, undergoing invasive procedures, to obtain necessary samples. They then wait for several weeks for the results.

Professor Ajit Lalvani, from the National Heart and Lung Institute at Imperial College London, who led the study team, said: "Our new test could revolutionise the way we manage people with suspected TB. At the moment, it can take quite a long time to figure out whether or not a patient has the disease, because it can mimic many different conditions and present in many different ways.

"Our study shows that by using the new blood test, together with the old skin test, we could establish if someone does not have TB within two days of them coming in for tests, allowing doctors to focus on other possible diagnoses. If we cannot rule out TB, we can then refer them for further testing to confirm the diagnosis. Using this new system would allow us to treat patients much more quickly and effectively," added Professor Lalvani.

The ELISpot-Plus device is not yet licensed and they intend to make it available to as large a number of TB patients as possible, including those in the developing world who carry the largest burden of TB, through ethical commercialisation.

The study looked at 389 patients recruited at Northwick Park Hospital in London and Heartlands Hospital in Birmingham. The researchers compared the performance of tuberculin skin testing and two blood tests, ELISpot and ELISpot-Plus, both individually and used in combination, in diagnosing patients with suspected active TB. The study was funded by the Wellcome Trust, the Sir Halley Stewart Trust and the UK Department of Health.

Britain is the only country in Western Europe where TB is on the rise and London, which carries almost half the national burden, is Europe's TB capital. Professor Lalvani leads a new, specially created TB Task Force at Imperial College London and its Academic Health Science Centre, Imperial College Healthcare NHS Trust. The TB Task Force aims to develop and deploy effective new weapons in the battle against TB, both in London and globally, through cutting-edge scientific research.

Professor Steve Smith, the Principal of the Faculty of Medicine at Imperial College London and Chief Executive of Imperial College Healthcare NHS Trust, said: "Our new Academic Health Science Centre integrates healthcare services with teaching and research to take the world's best research from bench to bedside - giving patients quicker access to new medical advances. We established Professor Lalvani's department because we value his patient-centred research and care deeply about London's growing TB problem. The work of Professor Lalvani and his team is an excellent example of world-class research providing significant benefits for our patients".

Laura Gallagher | alfa
Further information:
http://www.imperial.ac.uk

More articles from Studies and Analyses:

nachricht Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung

nachricht Scientists reveal source of human heartbeat in 3-D
07.08.2017 | University of Manchester

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Nagoya physicists resolve long-standing mystery of structure-less transition

21.08.2017 | Materials Sciences

Chronic stress induces fatal organ dysfunctions via a new neural circuit

21.08.2017 | Health and Medicine

Scientists from the MSU studied new liquid-crystalline photochrom

21.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>