Inhalation of nontuberculous mycobacteria is common for most people. Bacteria are found in water systems, soil and dust around the world and, for many, cause no harm.
For those with underlying conditions, nontuberculous mycobacteria (NTM) can infect the lungs and cause symptoms similar to those of tuberculosis. The inflammation can cause a chronic and sometimes bloody cough, as well as scarring, which can make respiratory infections such as bronchitis and pneumonia more common. Due to the slow growth of the bacteria, proper diagnosis and treatment can take months.
In a new study, researchers at Tulane University have developed a CRISPR-based platform to diagnose NTM infections where blood tests can return results in as little as two hours.
The preliminary findings, published in the American Journal of Respiratory and Critical Care Medicine, showed that the blood test was able to accurately identify more than 93% of patients with an NTM infection. Rapid and accurate diagnosis has never been more important as cases of NTM infections have continued to increase annually, spreading from subtropical regions to more temperate zones, in part due to global climate change.
“NTM infection is greatly underestimated, and due to its slow diagnosis, patients with NTM infection do not receive effective treatment,” said Bo Ning, corresponding author and assistant professor of molecular biology at the University of Medicine School of Medicine. Tulane. “Importantly, our blood test can analyze NTM DNA fragments in the bloodstream, thereby inferring a drug response, which is crucial for quickly determining treatment plans, capabilities that traditional diagnostic approaches cannot achieve. “.
The blood test is specifically designed to detect avium mycobacteria complex (MAC), one of the most common types of NTM and the most common cause of NTM-induced lung disease.
To identify an infection, the test detects NTM DNA fragments in the bloodstream. Current diagnostic methods rely on analysis of long-term cultures of slow-growing bacteria, which can lead to delays in diagnosis and treatment. And with more than 190 species of NTM, correctly diagnosing an infection can be difficult.
“Currently, a correct diagnosis and treatment can last more than six months,” Ning said. “Not only can our blood test provide same-day results, it can also be performed quickly in any clinic where blood can be drawn and does not require specialized training or equipment needed to analyze bacterial cultures.”
Ning said the United States could face a rise in NTM infections in the future and that accessible tests like this are vital to staying ahead.
In the future, he hopes to expand the types of NTM that CRISPR can detect and develop point-of-care tests for NTM detection.
“The goal is to reduce barriers to testing and diagnosis and prepare for a possible increase in NTM infections,” Ning said.
The study was conducted in collaboration with Oregon Health and Science University.