[Treatment of respiratory infection by Pseudomonas aeruginosa in adult patients within a hospital at home service: clinical characteristics and analysis of prognostic factors for relapse].

Introduction: Pseudomonas aeruginosa respiratory infections are associated with poor respiratory function, low quality of life, and a high relapse rate.

Methods: A 6-year prospective study (2000-2005) was carried out. Patients with P. aeruginosa respiratory infection admitted to a Hospital at Home service for parenteral antibiotic treatment were enrolled in the study. Clinical response to treatment, relapse, and relapse-free time, were analyzed as primary endpoints.

Results: A total of 111 episodes were recorded in 81 patients. Bronchiectasia was the most common associated disease (57%). Ceftazidime and tobramycin were the first-line therapies used (61%). The average length of stay was 14 days. Among the total, 80% of patients had severe/very severe respiratory obstruction, and 35% were culture-positive at the end of treatment. Median follow-up to relapse was 144 days; 65% of episodes relapsed. Relapse was associated with bronchiectasia, aerosol therapy, and more severe respiratory obstruction. In the patients with severe/very severe obstruction, there was a decrease in relapse-free time from 1080 to 139 days, in those with positive culture at the end of therapy from 248 to 78 days, and in those with resistance to any antipseudomonal antibiotic, from 390 to 97 days. On multivariate analysis, severity of respiratory obstruction and the antibiotic resistance were independent risk factors for relapse.

Conclusion: Patients infected by P. aeruginosa in poor clinical condition or showing resistance to any antipseudomonal antibiotics have a higher probability of relapse, and a shorter time to relapse than other patients with this infection. The Hospital at Home Service is a good approach to reducing the long-term hospital stay in these patients.