Non-tuberculous mycobacteria in patients with bronchiectasis

Area of Science:

• Pulmonology
• Infectious Diseases
• Microbiology

Background:

• Non-tuberculous mycobacteria (NTM) are widespread environmental bacteria.
• Individuals with pre-existing lung conditions, such as bronchiectasis, are at risk for NTM infections.
• The prevalence and clinical significance of NTM in bronchiectasis are not well-established.

Purpose of the Study:

• To determine the prevalence of NTM in patients diagnosed with bronchiectasis.
• To analyze the clinical characteristics and outcomes of bronchiectasis patients with NTM isolates.
• To identify the predominant NTM species in this patient population.

Main Methods:

• A prospective study enrolled 100 patients with bronchiectasis to assess NTM prevalence in sputum.
• A retrospective analysis reviewed clinical, microbiological, lung function, and radiological data of patients with NTM isolates over 11 years.
• Patients were categorized into groups based on bronchiectasis status and the number of NTM isolates.

Main Results:

• The prevalence of NTM in the studied bronchiectasis population was 2%.
• Mycobacterium avium complex (MAC) was the most common NTM species, significantly more prevalent in bronchiectasis patients (72%) compared to those without (9%).
• Multiple NTM isolates were more frequently smear-positive, and cavities were observed in 25% of these patients, often associated with MAC.

Conclusions:

• NTM infections are infrequent in non-cystic fibrosis bronchiectasis.
• Routine sputum screening is effective in detecting otherwise unsuspected NTM infections.
• MAC is the predominant NTM species identified in patients with bronchiectasis.