New blood tests for TB could speed up your diagnosis

London: The rapid blood tests currently in use can not exclude tuberculosis and should be replaced by more accurate tests, according to a British study published in The Lancet.

In the largest study to date on rapid tuberculosis tests used by the UK's National Health Service (NHS), a team led by researchers from Imperial College London has revealed that the available tests n & # 39; They were not sensitive enough to rule out a diagnosis of tuberculosis in suspected cases. have limited clinical use.

The research, published in the journal Lancet Infectious Diseases, also examined a new second-generation rapid blood test, developed at Imperial Oil, and revealed that it was significantly more accurate than existing tests.

According to the team, once implemented, the new test could allow doctors to detect or quickly rule out TB infection and help them distinguish between patients requiring further investigation and treatment of TB. those who do not do so and pose no infectious risk to others.

"Testing of thousands of patients is undergoing a diagnostic badessment of symptoms suggestive of TB, resulting in over 5,000 TB cases diagnosed each year," said Ajit Lalvani, chair of the National Heart and Infectious Disease Committee. Lung Institute of Imperial College London.

"Stopping the use of existing and inadequate tests could allow the NHS to save a lot of money. On the other hand, the new, faster, more accurate blood test will make it easier for the NHS to save money. improve and accelerate the badessment of the diagnosis of patients suspected of tuberculosis, "said Lalvani, director of the group. study.

Tuberculosis is a bacterial infection that affects the lungs and causes coughing, weight loss and fever. It is spread through droplets from coughs and sneezes from infected patients.

Diagnosis and early treatment of the disease are essential to the patient's health and to preventing the spread of TB to others. It is therefore necessary to have rapid and practical tests to exclude a diagnosis of tuberculosis in suspected cases on the basis of a blood sample.

The currently available rapid tests for TB used by the NHS, known as interferon-gamma release badays (IGRAs), can help indicate whether a patient is infected with tuberculosis by detecting his immune response to the bacterium of tuberculosis on the basis of a blood sample.

In the latest study, researchers compared commercially available IGRA tests with next-generation tests in 845 suspected TB patients in 10 NHS hospitals in England. Patients' blood samples were badyzed using two sets of tests, the results of which were compared to a confirmed diagnosis based on positive culture results.

The badysis of the results of the rapid test revealed that the second-generation test had a diagnostic sensitivity of 94% in patients with confirmed TB, which means that it gives a positive result for 94% of patients infected, which is significantly higher than the others. commercially available IGRA tests (between 67.3% and 81.4%).

The results indicate that the test would be much more accurate in eliminating tuberculosis infection in case of suspected tuberculosis, thus saving time and resources while allowing patients to receive treatment faster. .