Giulia Bonaiti

Characterizing Non-Tuberculous Mycobacteria Infection in Bronchiectasis

Chronic airway infection is a key aspect of the pathogenesis of bronchiectasis. A growing interest has been raised on non-tuberculous mycobacteria (NTM) infection. We aimed at describing the clinical characteristics, diagnostic process, therapeutic options and outcomes of bronchiectasis patients with pulmonary NTM (pNTM) disease. This was a prospective, observational study enrolling 261 adult bronchiectasis patients during the stable state at the San Gerardo Hospital, Monza, Italy, from 2012 to 2015. Three groups were identified: pNTM disease; chronic P. aeruginosa infection; chronic infection due to bacteria other than P. aeruginosa. NTM were isolated in 32 (12%) patients, and among them, a diagnosis of pNTM disease was reached in 23 cases. When compared to chronic P. aeruginosa infection, patients with pNTM were more likely to have cylindrical bronchiectasis and a “tree-in-bud” pattern, a history of weight loss, a lower disease severity and a lower number of pulmonary exacerbations. Among pNTM patients who started treatment, 68% showed a radiological improvement, and 37% achieved culture conversion without recurrence, while 21% showed NTM isolation recurrence. NTM isolation seems to be a frequent event in bronchiectasis patients, and few parameters might help to suspect NTM infection. Treatment indications and monitoring still remain an important area for future research.

History of lung volume reduction procedures

Lung volume reduction (LVR) procedures for emphysematous patients were firstly introduced in the second half of the twentieth century. Over time, from the first invasive surgical procedures, new less invasive techniques have been conceived. In regards to the surgical approach, the adoption of VATS and the execution, in selected centers, of a non-resectional approach, with folding of less functional lung tissue, reduced mortality and adverse events risks. As regards to the bronchoscopic approach, endobronchial valves (EBV) and intrabronchial valves (IBV) were initially proposed in the early 2000s to obtain segmental or lobar atelectasis of the more compromised lung parenchyma. Despite showing promising results with respect to improvement of pulmonary function tests, particularly forced expiratory volume in 1st second (FEV1), and quality of life, and a good safety profile, valves showed disappointing results in presence of collateral ventilation, such as in cases of incomplete fissures. To overcome this technical issue, in the last 10 years, endobronchial coils have been designed and used. Having a compressive effect on the lung parenchyma where they are located, they are not affected by collateral ventilation. Randomized control trials (RCTs) on endobronchial coils showed a significant improvement in FEV1 and quality of life, however this technique was not immune to side effects, particularly low respiratory tract infections and pneumothoraces. Besides bronchial valves (BV) and coils, airway by-pass stents have also been evaluated in a RCT but without reaching the desired endpoints. Other innovative procedures recently considered and delivered through bronchoscopy regards thermal energy, with vapour therapy, to achieve a scarring reaction of the emphysematous lung parenchyma, and polymeric foams used as lung sealants to achieve absorptive atelectasis. In conclusion, LVR procedures may be considered in carefully selected patients with symptomatic emphysema and severe lung hyperinflation, and might be personalized according to the anatomical characteristics of emphysematous area.