Florida is a hot spot for a pulmonary disease caused by non-tuberculous mycobacterium, or NTM for short. This chronic lung infection can cause symptoms similar to tuberculosis, including persistent cough, shortness of breath, fever, night sweats and weight loss.
Among the many challenges for the 220,000 people in the U.S. with NTM is the time it takes to diagnose it. Samples of coughed-up sputum must be cultured in a laboratory, which can take four to six weeks.
A new test developed by Tulane University could speed up that process by relying on DNA technology to identify the most common types of NTM within hours.
“The same day, you know the result,” said Bo Ning, assistant professor of molecular biology at Tulane University School of Medicine in New Orleans.
Ning and colleagues described their new diagnostic platform, called CANDI or CRISPR-assisted Nanodroplet Differential Identification, in the journal Science Translation Medicine in September.
Tests showed it was 97 percent effective at identifying “up to 15 clinically relevant species and subspecies” of NTM bacteria, according to the research.
It's not widely available yet and still needs FDA approval. The cost should be only $3 to $5 per test, according to Ning.
The faster testing technology could benefit patients, said Dr. Anthony P. Cannella, associate professor of medicine at the University of South Florida's Morsani College of Medicine.
"I do think that this kind of technology would help accelerate diagnoses,” said Cannella, a prominent NTM doctor who was not involved in the Tulane research.
"It will provide insight and some clarity for these cases where we don't know what's going on, and it could be cancer or a fungal infection, or something else, and ends up being an NTM, which in itself is still a very serious diagnosis,” he said.
“But it wouldn't give us necessarily, at this juncture, insight into which antimicrobials to use for these patients," he said.
“It'll tell us who the bad actor is, but it doesn't describe what we need to use to kill it.”
NTM bacteria are found in water and soil, and are notoriously difficult to eradicate.
Treatments for NTM can last months to years, and patients can be reinfected by the water in their homes.
The incidence of NTM rises 8.2% per year, according to NTM Info and Research in Palmetto Bay. A study on patients in South Korea with NTM found an 18% mortality rate in five years.
Ning said his team is also working to develop a test that could detect drug resistance in NTM.
Cannella said he believes that aspect would be even more helpful.
“What I foresee is that eventually they will have the ability to look for certain resistance markers to certain antimicrobials up front, and then we don't have to wait for it to grow. Now, that's a crystal ball,” he said.
“If I'm going to start somebody on antimicrobials, I need to know which drugs have the capability of killing the organism and achieving a clinical cure.”
