TB test offers patients quicker and easier diagnosis

Jun 01, 2007

A new test for diagnosing TB offers a quick and simple alternative to existing three-day methods, according to research published today in the journal Clinical Infectious Diseases.

The study shows that the test, which involves taking three sputum samples from a patient over the course of one day, is just as effective as other more invasive and complicated testing methods, which take three days.

For the new test, patients use a nebuliser to inhale salty water, or hypertonic saline, for twenty minutes. This enables them to produce sputum samples from deep inside the lungs. The samples can then be analysed for traces of mycobacterium tuberculosis, the bacterium which causes most cases of TB.

Other procedures for testing for TB are gastric washing and bronchoscopy with bronchoalveolar lavage. These invasive procedures involve placing tubes in the stomach, to collect samples of mucus swallowed during the night, or the broncial tubes, to try to wash bacteria from infected lung tissue. Patients have to be in hospital for three days to allow these samples to be collected and analysed, delaying the start of treatment.

Such tests are given where patients have symptoms or chest radiography results that suggest the patient might have TB and they are unable to cough up a sputum sample.

The new research, which was carried out by researchers from Imperial College London and Northwick Park Hospital NHS Trust, showed that the new test is just as effective, if not more so, than existing methods for diagnosing TB.

In the 140 people who were examined, use of 3 sputum
specimens correctly detected TB in 39% of the patients. Gastric washing detected TB in 30% of the same patient sample. No additional cases were diagnosed in the 21 patients who underwent bronchoscopy.

Dr Robert Davidson, from the Division of Medicine at Imperial College and the Department of Infection and Tropical Medicine at Northwick Park Hospital NHS Trust, and one of the authors of the research, said: "This is a simple method of ollecting bacteria from individuals with the early stages of TB, and who are unable to cough sputum samples. By doing all the tests in one day, we can start treatment sooner and get patients home sooner. Previously we relied on bronchoscopy or gastric washings, which were uncomfortable for the patient and required a longer stay in hospital. The patient breathing nebulised hypertonic saline feels little or no unpleasant sensation, and it is a very cheap test".

According to the Health Protection Agency, the incidence of TB in the UK is increasing, with around 8,000 new cases a year. Cases in the UK are predominantly confined to the major cities and about 40 per cent of all cases are in London. TB is also a major global problem: an estimated one-third of the world's population - nearly two billion people - are infected. Nine million people a year develop the active disease worldwide, which kills two million each year.


Source: Imperial College London

Explore further: Heat blamed for spray vaccine's failure against swine flu

add to favorites email to friend print save as pdf

Related Stories

Korean tech start-ups offer life beyond Samsung

4 hours ago

As an engineering major at Seoul's Yonsei University, Yoon Ja-Young was perfectly poised to follow the secure, lucrative and socially prized career path long-favoured by South Korea's elite graduates.

Fresh nuclear leak detected at Fukushima plant

16 hours ago

Sensors at the Fukushima nuclear plant have detected a fresh leak of highly radioactive water to the sea, the plant's operator announced Sunday, highlighting difficulties in decommissioning the crippled plant.

Spacewalking astronauts route cable in 1st of 3 jobs

16 hours ago

(AP)—Spacewalking astronauts routed more than 300 feet (90 meters) of cable outside the International Space Station on Saturday, tricky and tiring advance work for the arrival of new American-made crew ...

Recommended for you

Trapping the Ebola virus in transit

46 minutes ago

The deadly Ebola virus makes use of host mechanisms – including a specific type of membrane-bound calcium channel – to gain entry into the cell cytoplasm. LMU researchers now show that blocking this channel ...

Saudi reports 10 MERS deaths in a week

52 minutes ago

Ten more people in Saudi Arabia have died from MERS over the past week, health ministry figures showed on Friday, after an international mission urged extra measures to combat the virus.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.