Short-term Tolerance to Inhaled Antibiotics in Patients With Bronchial Infection not Associated With Cystic Fibrosis

Introduction

The use of intravenous antibiotic formulations delivered by inhalation is controversial. Tolerance can be an issue and some treatment guidelines discourage this route of administration if the same antibiotic is available in an inhalation formulation.

Material and methods

This was a retrospective, observational, single-center study comparing tolerance to three antibiotics delivered by nebulization (intravenous formulations of ampicillin and gentamicin, and an inhalation formulation of colistimethate sodium) in patients with bronchial infection (BI), chronic bronchial infection (CBI), and/or recurrent respiratory infections. The study also aimed to identify factors potentially associated with tolerability.

Results

A total of 330 antibiotic tolerance tests were performed in 135 patients (mean age 68 years; 48.9% female; mean post-bronchodilator FEV₁% predicted 65.9%). Of these patients, 62.2% had bronchiectasis and 39.3% had chronic obstructive pulmonary disease (COPD). The best tolerated antibiotic was colistimethate. Overall, 89.6% of colistimethate doses were tolerated, compared to 69.5% of inhaled gentamicin doses (P < 0.001) and 69.1% of ampicillin doses (P < 0.001). Compared with colistimethate administration, the odds of intolerance were 5.69 times higher for gentamicin (P < 0.001) and 6.21 times higher for ampicillin (P < 0.001). In the univariate analysis, factors that may have been associated with antibiotic intolerance included smoking habit, worse post-bronchodilator FEV₁% predicted and a diagnosis of COPD. In the multivariate analysis, after adjustment for antibiotic type, smoking habit, post-bronchodilator FEV₁ and COPD diagnosis, the only factor influencing tolerance was the type of antibiotic used.

Conclusion

In patients with BI and/or CBI and/or recurrent respiratory infections, inhaled sodium colistimethate is significantly better tolerated than intravenous formulations of gentamicin and ampicillin for the inhalation route. The only factor influencing tolerance is the type of antibiotic used.