[Effects of azithromycin on the virulence of Pseudomonas aeruginosa].

Pseudomonas aeruginosa is a saprophyte opportunistic bacteria which frequently colonizes the respiratory tract of patients presenting a severe chronic bronchitis pathology. Secreting a number of exotoxins and enzymes inducing an inflammation and necrosing of the surrounding tissues, it provokes irreversible pulmonary lesions. Different experimental in vitro works evidenced macrolides activity on the production and/or secretion of these factors, with a diminution of elastase, protease, lecithinase and D-nase synthesis. Among the macrolides, azithromycin seems to have the most pronounced activity. In vivo, some patients suffering from bronchiolitis or cystic fibrosis have been clinically improved with a treatment using erythromycin, or clarithromycin or azithromycin. These very preliminary results demand to be confirmed but the macrolides could allow a decrease of Pseudomonas aeruginosa pathogenicity and thus stop the deterioration of pulmonary functions.