The efficacy of the long-term treatment with macrolides in patients with bronchiectasis colonised by P. aeruginosa

Abstract number: 1134_02_78

Schmidt-Ioanas M., Allewelt M., Polzin A., Lode H.

Background:

Although macrolides have no intrinsic antipseudomonal activity, these drugs appear effective in controlling infection by P. aeruginosa through mechanisms such as disruption of quorum sensing or anti-inflammatory effects.

Objectives:

The aim of our prospective study was to evaluate the efficacy of macrolides in patients with bronchiectasis infected and colonised by P. aeruginosa.

Methods:

The study included hospitalised patients with CT evidence of bronchiectasis and presenting an acute exacerbation by P. aeruginosa, isolated in sputum. Microbiological findings, clinical data and treatment recommendations were recorded at admission and at the end of therapy. Patients completed daily diary cards for symptoms and PEF values. Patients were followed for 1 year.

Results:

Twenty-two patients (14 men, mean age 57.3 ± 14.5) with bronchiectasis and P. aeruginosa infection were included. During hospital stay, patients were treated with at least two susceptible antipseudomonal drugs, according to the antibiogram (usually beta-lactam plus aminoglycoside) for a period of 16.9 ± 1.6 days. An oral macrolide (azithromycin 250 mg x 3 days/week in 10 patients, clarithromycin 500 mg daily in 12 patients) was further administrated for 4.9 ± 1.9 months. At the end of long-term therapy, 11 (50%) patients showed no evidence of P. aeruginosa in sputum, 8 (36.3%) patients still presented P. aeruginosa in sputum and 3 (13.6%) discontinued the treatment after less that 1 month because of adverse events. All patients had a significant reduction of sputum volume (83.3 ml/day before therapy vs. 22.5 ml/day at the end of therapy, p = 0.03) and of the mean number of exacerbations during follow-up (2.4 in the previous year vs. 1.2 in the follow-up year, p = 0.01). An increase of the mean PEF value was also noted, although statistically not significant (373.2 ± 43.5 l/min before therapy vs. 489.2 ± 23.5 l/min at the end of therapy, p = 0.3)

Conclusion:

These observational findings suggest that macrolides may have a role in modulation of P. aeruginosa colonisation in patients with bronchiectasis.