Nontuberculous mycobacteria (NTM) isolation is a frequent event in bronchiectasis patients, a study published in the International Journal of Molecular Sciences has confirmed.
According to the report, “Characterizing Non-Tuberculous Mycobacteria Infection in Bronchiectasis,” it is extremely challenging to treat NTM infection in bronchiectasis patients. Moreover, using general recommendations established for the general population with NTM for bronchiectasis patients may not be adequate. So, the report suggests, it is important to characterize and closely monitor this group of patients in order to develop more appropriate treatment approaches.
To this aim, a team of researchers led by Stefano Aliberti, MD, of the Department of Pathophysiology and Transplantation at the University of Milan, Italy, enrolled 261 adult patients with bronchiectasis at the San Gerardo Hospital in Monza, Italy, during the stable state of the disease.
The researchers identified three groups of patients: Those with pulmonary NTM, those with an infection of the bacterium Pseudomonas aeruginosa, and those with a chronic infection due to bacteria other than P. aeruginosa.
When the team compared patients with pulmonary NTM to those with P. aeruginosa infection, they found that those with pulmonary NTM were more likely to have cylindrical bronchiectasis, which is the mildest form of the disease, as well as a history of weight loss, and fewer pulmonary exacerbations.
Following antibiotic treatments, 68% of the patients with pulmonary NTM showed a radiological improvement, and 37% achieved culture conversion indicative of the patient being cured or recovering from the infection, while 21% showed NTM isolation recurrence.
The authors concluded that NTM isolation is a frequent event in bronchiectasis patients, especially among those with milder disease.
“Future studies should focus on determining whether patients with NTM isolation and bronchiectasis may benefit from different diagnostic criteria to define [pulmonary] NTM disease,” they wrote in the report. They also noted that, based on the often unsatisfactory treatment outcome, bronchiectasis patients with pulmonary NTM may require specific treatments and that more research is needed in this area.
Chronic infection of the airways is a critical aspect of bronchiectasis, causing inflammation and structural damage to the lungs. The most frequent infections found in bronchiectasis patients include Haemophilus influenzae, P. aeruginosa, Moraxella catarrhalis and Staphilococcus aureus. NTM is increasingly recognized as also being associated with the disease, and has been reported to have a frequency between 1% and 18% among bronchiectasis patients.