The diagnosis of latent tuberculosis: Nice public consultation on the use of interferon-gamma test

– For those with CD4 cell counts and at less than 200, is to run a test and a TST IGT. If the test is positive assess for active TB. Consider treatment of latent tuberculosis if active disease is excluded.2. Recently, selective immunological tests were developed using two antigens of tuberculosis, ‘the first target antigen secretion 6 ‘ and’ the culture filtrate protein 10′ , which are not present in BCG, and are found only in some species of environmental mycobacteria. These tests are designed to be more precise, eliminating false positives, and to be better correlated with latent infection or dormant organisms.

Based on a detailed analysis of this further research, the director of the Independent Development Group concluded that the relative benefit of IGT over TST in determining the need for treatment of latent tuberculosis infection n ‘It is not clear – and in the case of young children, felt that IGT may even perform worse. However, the GDG has made recommendations in populations in which they felt to IGT obvious advantage, especially in cases where IGT would reduce the uncertain diagnosis of TST. Recommendations contained in the draft directive, so are the following:

– Using the Mantoux test is repeated. If positive, taking into account the history of BCG, to make a clinical assessment to exclude active disease and consider treatment of latent tuberculosis.

ACG patients typically have eyes that are slightly smaller than normal, with a goal that is important for the size of the eyes, and an unusually short axis length of the eye.1038/ng. The disease develops slowly and can often be managed with the drops and laser surgery.

Dr Fergus Macbeth, director of the Center for Clinical Practice at NICE said: ‘If TB is left untreated, it can be very serious or fatal, but treatment is very effective up to 15 percent of adults with latent tuberculosis will develop active TB. at some point in their life and the risk in children may be much higher in people who are immunocompromised -. latent tuberculosis is important in controlling the disease.

– The new arrivals from countries with high prevalence of less than 5 years:

4. The draft guideline is available on the NICE website.

– A Mantoux test should be performed. Those with positive results should then be considered for IGT.

Initial indications NICE acknowledged that there was a lack of good quality evidence to see whether interferon-gamma tests are acceptable to patients and are more effective than the tuberculin skin test to predict the subsequent development of active tuberculosis, or diagnose or rule out active TB present. NICE recommended that further research to compare the strategies only skin test skin test and interferon-gamma test, if positive, and interferon-gamma test only. Concerns were also raised on the appropriateness of IGT use in current clinical practice during the review process for which the original NICE guideline on the diagnosis and treatment of tuberculosis.

3. NICE was asked by the Ministry of Health to produce a short clinical guideline of interferon-gamma immunological tests for the diagnosis of latent TB and make recommendations on:

– For people with HIV and CD4 counts of 200-500, or IGT IGT test alone and test with TST competitors. If the test is positive, evaluate active tuberculosis. Consider the treatment of activity TB.

The National Institute for Health and Clinical Excellence has today published its draft guideline on the diagnosis of latent TB infection in children and adults. A partial update of the 2006 guidelines, the project focuses on the diagnosis of latent TB with the tuberculin skin test and the new interferon-gamma test . The project addresses the diagnostic strategy is the most accurate in the diagnosis of latent TB in adults and children who have recently arrived from countries where TB is common in adults and children who have been in close contact with TB patients active and in immunocompromised adults and children.

He continued. ‘The new gamma-interferon tests for latent TB may offer some advantages over the current test internationally recognized standards – the Mantoux test, however, despite the studies that were conducted by the management of tuberculosis when the original was published NICE , important questions remain unanswered about the potential role of these new tests in clinical practice in the United Kingdom. The draft directive therefore adopts a prudent and pragmatic approach, recommending that in many cases the most effective for the diagnosis of latent TB infection is Mantoux test result, depending on the result, a test of glucose intolerance. ‘

2. It may take several years for a person infected with M. tuberculosis develop active tuberculosis.

1. is an infectious disease caused by the bacterium Mycobacterium tuberculosis, also called ‘the bacillus of tuberculosis. TB usually affects the lungs but can also affect other parts of the body. The symptoms of TB are varied and depend on the site of infection. General symptoms may include loss of appetite, weight loss, night sweats

6. Almost all cases of clinical tuberculosis in the United Kingdom contracted the disease by inhaling infected droplets from a person with infectious respiratory active TB. The initial infection can be eliminated, remain latent or progress of active TB in the weeks or months.

5. Although rates of disease are now very low in some parts of the country, in other areas, especially cities, the disease rates are higher and, in some cases to increase. For example, two out of five cases of TB occur in London. Specific groups are disproportionately affected by tuberculosis among the homeless and those in social housing, new entrants, especially those from regions with a high prevalence of tuberculosis and who live in the city center

– What is the most accurate diagnostic strategy for the diagnosis of latent TB in adults and children who are recent arrivals from countries with high prevalence?

– What is the most accurate diagnostic strategy for the diagnosis of latent TB infection in children?

The parties wishing to submit comments on the draft order are invited to do so via the NICE website on August 5, 2010. NICE plans to publish final guidelines in December 2010.

1. There is no gold standard test for latent TB. The diagnosis in the past relied on the TST, but this has a low specificity, there was the BCG vaccination or exposure to the environment mycobacteria, which can lead to false positive results.

The test results must be interpreted within a certain time, and patients who do not return, or delay the return will be no result or perhaps inaccurate