Antimicrobial therapy of Pseudomonas pulmonary exacerbations in cystic fibrosis. A prospective evaluation of netilmicin plus azlocillin versus netilmicin plus ticarcillin.

High-dose anti-Pseudomonas chemotherapy is mandatory in the treatment of acute pulmonary exacerbations in patients with advanced cystic fibrosis and Pseudomonas aeruginosa isolated from their sputum. However, neither the regimen itself nor its objective evaluation have been optimized yet. In a prospective controlled evaluation 42 such exacerbations were treated for two weeks with netilmicin combined by randomisation with either azlocillin or ticarcillin. Other aspects of therapy were constant. The two therapy groups were comparable in all aspects. Both regimens produced similar improvements in clinical, radiological, laboratory, bacteriological and pulmonary function measurements. Concentrations of sputum bacteria were significantly reduced; transient eradication was documented in 29% and correlated with antibiotic susceptibility of the initially isolated Pseudomonas strains. The highly dosed antibiotics were well tolerated and emergence of resistance was rarely observed. It is concluded that both antibiotic combinations are beneficial and safe in cystic fibrosis. Monitoring of such intensive hospital treatment must include multiple parameters.