News in the fight against tuberculosis: Limitations of the QFT+ test revealed!

News in the fight against tuberculosis: Limitations of the QFT+ test revealed!

Tuberculosis, often known as “consumption,” is one of the oldest and deadliest diseases known to mankind. The crucial discovery of the pathogen, Mycobacterium tuberculosis, dates back to 1882, when the German physician Robert Koch identified the disease. However, today there are effective treatment options with antibiotics that have significantly improved the prognosis for those affected. It is estimated that around 25% of people worldwide carry the pathogen, although the infection is often inactive. Active tuberculosis poses a serious risk, particularly for people with weakened immune systems, such as those infected with HIV or those who have had organ transplants.

In a comprehensive study conducted between 2015 and 2019, Professor Martina Sester and her colleagues examined the effectiveness of the QuantiFERON-TB Gold Plus test (QFT+) in immunocompromised patients. This blood test measures the immune response to the tuberculosis pathogen. However, it turns out that if the immune system is weakened, the immune response can be lower, which can lead to false negative results. The study included over 2,600 patients from eleven European countries, making it the largest multicenter study on this topic uni-saarland.de reported.

Results and challenges of the QFT+ study

Of the 2,600 people tested, 1,788 had weakened immune systems, while 861 served as controls. The results showed that the QFT+ test alone is not sufficient to reliably diagnose active tuberculosis. The study found that after two years, no new active tuberculosis occurred in the test subjects who tested positive or negative - with the exception of a few individual cases in HIV-positive people. Furthermore, the QFT+ test does not meet the requirements of the World Health Organization (WHO) and it is recommended that better tests for the diagnosis of tuberculosis be developed. Expected future risk assessments should take into account additional factors such as HIV status and general immune status.

The study was part of the TBnet research network, which has been investigating progressive approaches to improve the diagnosis, treatment and prevention of tuberculosis since its founding in 2006. TBnet now includes over 500 members from more than 70 countries and is particularly concerned with multi-resistant forms of tuberculosis.

QuantiFERON-TB Gold Plus test and its application

The QuantiFERON-TB Gold test is a specific blood test for detecting latent or active tuberculosis infections. Working as an interferon gamma release assay (IGRA), it measures the immune response to tuberculosis bacteria in just one visit. Of particular note, the test is not affected by previous BCG vaccinations, making it attractive to many patients, including those who have received the vaccination. How labfinder.com describes, the test is not only precise but also safe to use, with typical test results available within one to three days.

Specific groups should consider testing, including people who have had close contact with tuberculosis patients, health care providers, people with weakened immune systems, and travelers to regions with high TB ​​prevalence. Performing the test requires only a blood draw, which is completed in a few minutes, and no special preparations are necessary other than general hydration for easier blood collection.

If the test results are positive, a doctor should be consulted immediately for further examinations, such as a chest x-ray or a sputum test. This makes it possible to assess whether the tuberculosis infection is latent or active. The recommended treatments are crucial to counteract the emergence of multidrug-resistant forms of tuberculosis, which is also of cdc.gov is affirmed.