Treatment of acute exacerbation of severe-to-very severe COPD with azithromycin in patients vaccinated against Streptococcus pneumoniae

Sixty-five consecutive eligible adult patients, who were treated as outpatients for stable severe-to-very severe COPD, were enrolled in the study. All of them received 23-valent pneumococcal capsular polysaccharide vaccine intramuscularly. Patients were seen monthly, as well as whenever they had symptoms suggestive of an exacerbation, at our outpatient clinic. Eighteen out of 65 patients suffered from acute exacerbation (AECOPD). Three of these patients presented two episodes of AECOPD. Patients with an acute exacerbation of COPD received azithromycin 500 mg/day once daily for 3 days and a short course of oral prednisolone 25 mg/die. In 16 cases, a single species was isolated, while in the remaining 5 cases at least two species were recovered. Clinical cure or improvement at the end of therapy (3-5 days post-therapy) was reported in 17 episodes of AECOPD with no relapse at the late post-therapy (10-14 days after the completion of treatment). Bacteriologic eradication or presumptive eradication rates at the end of therapy were 86% (24 out of 28 isolates). Azithromycin eradicated all isolates of Haemophilus influenzae, Moraxella catarrhalis, H. parainfluenzae, Klebsiella pneumoniae, and Klebsiella spp. isolated at baseline. Eradication of Sta aureus occurred in 1 of 3 isolates whereas azithromycin was unable to eradicate Pseudomonas aeruginosa isolates. Our data seem to indicate that pneumococcal vaccination reduces the possibility that an AECOPD is caused by Streptococcus pneumoniae. This finding allows the use of antibiotics such as azithromycin, which, otherwise, should be avoided because of resistances.