Results from a recent study published in the International Journal of Mycobacteriology showed that, compared to other pathogens, colonization with P. aeruginosa has the highest influence on the functional, clinical and radiological status of patients with non-CF bronchiectasis (NCFBE). The cause of NCFBE is not entirely understood, but many cases are related to damage caused by lung infections, structural problems in the lung, or underlying systemic diseases. Over half of NCFB cases do not have an identifiable cause.

In their study titled “Chronic infection with non-tuberculous mycobacteria in patients with non-CF bronchiectasis: Comparison with other pathogens,” Stephano Aliberti from the Health Science Department at the University of Milan Bicocca in Italy and colleagues compared the clinical characteristics of patients with non-cystic fibrosis bronchiectasis (NCFBE) that had chronic infections with non-tuberculous mycobacteria (NTM) with patients that had NCFBE with chronic infections with Pseudomonas aeruginosa or other colonizations.

This was an observational, perspective study of consecutive NCFBE in a total of 146 patients with history of chronic infection. The researchers divided these pateints in three groups: Group A included 19 patients with NTM; Group B included 34 patients with P. aeruginosa and Group C included 93 patients with other types of pathogens. Patients with both NTM and another pathogen were included in Group A. Data analyses revealed that 6 patients of group A had only NTM isolation, 7 patients had NTM and P. aeruginosa co-infection and 6 patients had NTM and another pathogen.

The research team found that the most common pathogens non-tuberculous mycobacteria found in 15 patients was Mycobacterium avium complex. Active treatment was prescribed for a total of 4 patients with non-tuberculous mycobacteria. Compared to patients who were colonized by P. aeruginosa, results showed that in patients affected by non-tuberculous mycobacteria, pulmonary infection was less severe and had less clinical, functional and radiological involvement.

Based on the results, the researchers concluded that colonization with P. aeruginosa might have the highest influence on the clinical, functional and radiological status of patients with non-CF bronchiectasis. Since it is complex to distinguish between NTC versus other pathogen colonisations, in the study authors recommend that according to the international guidelines, all patients with non-CF bronchiectasis should be examined for atypical mycobacteria.