Eradicating uncertainty: A review of Pseudomonas aeruginosa eradication in bronchiectasis

^CHEST

Dr. Ashley Losier

^CHEST

Dr. Ryan S. Threadgill

Airways Disorders Network

Bronchiectasis Section

Bronchiectasis patients have dilated airways that are often colonized with bacteria, resulting in a vicious cycle of airway inflammation and progressive dilation. Pseudomonas aeruginosa is a frequent airway colonizer and is associated with increased morbidity and mortality in cystic fibrosis (CF) and noncystic fibrosis bronchiectasis (NCFB).¹

Both CF and NCFB guidelines recommend eradication of P. aeruginosa upon detection.² In CF, the guidelines suggest use of inhaled tobramycin, without systemic antibiotics.³ Optimal NCFB eradication regimens remain unknown, though recent studies demonstrated inhaled tobramycin is safe and effective for chronic P. aeruginosa infections in NCFB.⁴

The 2024 meta-analysis by Conceiçã et al. revealed that P. aeruginosa eradication endures more than 12 months in only 40% of NCFB cases, but that patients who received combined therapy—both systemic and inhaled therapies—had a higher eradication rate at 48% compared with 27% in those receiving only systemic antibiotics.⁵ They found that successful eradication reduced exacerbation rate by 0.91 exacerbations per year without changing hospitalization rate. They were unable to comment on optimal antibiotic selection or duration.

A take-home point from Conceiçã et al. suggests trying to eradicate P. aeruginosa with combined systemic and inhaled antibiotics if possible, but other clinical questions remain around initial antibiotic selection and how to treat persistent P. aeruginosa.

References

1. Finch, et al. Ann Am Thorac Soc. 2015;12(11):1602-1611.

2. Polverino, et al. Eur Respir J. 2017;50:1700629.

3. Mogayzel, et al. Ann ATS. 2014;11(10):1511-1761.

4. Guan, et al. CHEST. 2023;163(1):64-76.

5. Conceiçã, et al. Eur Respir Rev. 2024;33:230178.