Antibiotic strategies for eradicating Pseudomonas aeruginosa in people with cystic fibrosis.

BACKGROUND: Lower respiratory tract infection with Pseudomonas aeruginosa (P. aeruginosa) occurs in most people with cystic fibrosis. Once chronic infection is established, P. aeruginosa is virtually impossible to eradicate and is associated with increased mortality and morbidity. Early infection may be easier to eradicate.

OBJECTIVES: To determine whether antibiotic treatment of early P. aeruginosa infection in children and adults with cystic fibrosis eradicates the organism and improves clinical and microbiological outcome.

SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Date of most recent search: May 2004

SELECTION CRITERIA: We included randomised controlled trials of people with cystic fibrosis, in whom P. aeruginosa had recently been isolated from respiratory secretions. We compared combinations of inhaled, oral or intravenous antibiotics with placebo or usual treatment (or both) or other combinations of inhaled, oral or intravenous antibiotics. We excluded non-randomised trials, cross-over trials, and those utilising historical controls.

DATA COLLECTION AND ANALYSIS: Both authors independently assessed selected trials, assessed methodological quality and extracted data.

MAIN RESULTS: The search identified 15 trials. Three trials (69 participants) were eligible for inclusion. There is evidence from two randomised controlled trials, of questionable methodological quality, that treatment of early P. aeruginosa infection with inhaled tobramycin results in microbiological eradication of the organism from respiratory secretions more often than placebo and that this effect may persist for up to 12 months, however incomplete data from one of the trials precludes an accurate analysis. One randomised controlled trial of oral ciprofloxacin and nebulised colisitin versus usual treatment was identified. This trial was of poor methodological quality. The results suggested treatment of early infection results in microbiological eradication of P. aeruginosa more often than usual treatment, after two years, RR 0.24 (95% CI 0.06 to 0.96). There is insufficient evidence to determine whether antibiotic strategies for the eradication of early P. aeruginosa decrease mortality or morbidity, improve quality of life, or are associated with adverse effects compared to placebo or standard treatment.

AUTHORS' CONCLUSIONS: From the three trials included in this review, there is some evidence that antibiotic treatment of early P. aeruginosa results in short-term eradication but it remains uncertain whether there is clinical benefit to people with cystic fibrosis.