New Tuberculosis Test Won't Need Sputum Samples for Diagnosis

A more simplified process of Tuberculosis (TB) testing, and a cheaper one at that, could be on the way as researchers from the Stanford University School of Medicine were able to uncover a gene expression "signature" that can tell whether someone has active TB via a simple blood test.

The new screening procedure for the diagnosis of active TB was detailed in a study, which was published online last Friday, Feb. 19, 2016, in the Lancet Respiratory Medicine. The new blood test could pave the way for a new screening without the need to ask the patient to produce and cough up phlegm samples.

"If someone can't produce adequate sputum, or if you have a kid who can't follow directions," then it would be hard to diagnose them, said Tim Sweeney, MD, PhD, one of the authors of the study.

Significance of the Study

The positive development that goes along with this study is significant not only in providing a more accurate test to identify members of the population with active tuberculosis but also in evaluating the progress of patients and to see how well they respond to different treatments.

"Thus, it can be used not only for diagnosis and to inform treatment, but also to study the effectiveness of different treatments. The test's hugely accurate negative response would be especially helpful in monitoring the effectiveness of treatments during clinical trials," said Purvesh Khatri, PhD, assistant professor of medicine and senior author of the paper, via a news release from the university.

Tuberculosis By The Numbers

According to the World Health Organization (WHO), TB was the cause of death for around 1.5 million people back in 2014, about 10 percent of which are children. Those who come from low and middle-income countries are more prone to the disease with more than 95 percent of TB deaths occurring in those countries.

The leading health agency in the world estimates that there were about 43 million lives that were spared from the disease because of diagnosis and treatment between 2000 and 2014. The death rate from TB was reduced to 47 percent from 1990 up until 2015. And, through the newly adopted Sustainable Development Goals, the WHO hopes to put an end to the TB epidemic by 2030.

TB Definition and Symptoms

TB is an infectious bacterial disease that is caused by the pathogenic bacterial species called Mycobacterium tuberculosis. This type of bacteria commonly affects the lungs and can be spread from one person to another through droplets from the throat and lungs of people with the active respiratory disease.

Some of the symptoms of TB are coughing, which may include sputum or blood, chest pains, weakness, weight loss, fever and night sweats. The respiratory illness can be treated with the use of antibiotics for a period of six months.