Reduction in prevalence of chronic Pseudomonas aeruginosa infection at a regional pediatric cystic fibrosis center.

Various management strategies were introduced at the Leeds Regional Cystic Fibrosis (CF) Unit in an attempt to reduce the prevalence of chronic Pseudomonas aeruginosa respiratory infection, previously thought to be inevitable in most children with CF. These included neonatal screening (1975), regular microbiological monitoring (1975), early antibiotic treatment of first isolations of P. aeruginosa (1985), intensive intravenous antibiotic treatment where nebulized antibiotics failed to eradicate P. aeruginosa (1988), and separate clinics for patients chronically infected with P. aeruginosa and uninfected patients (1991). The aim of this study was to assess the impact of these interventions. All 232 patients receiving full-time care at the Leeds Paediatric CF Centre during the period January 1990-December 2000 were categorized into four groups: never grown P. aeruginosa; free of P. aeruginosa for at least 1 year; intermittent grower of P. aeruginosa with </=50% of months with samples positive for P. aeruginosa over the previous 12 months; and chronic P. aeruginosa infection with >50% of months with samples positive for P. aeruginosa over the previous 12 months. The yearly prevalence of patients having chronic P. aeruginosa infection fell significantly during the study, from 24.5% in 1990 to 18.1% in 2000 (P < 0.05), despite an increase in mean age of patients from 7.73 to 9.42 years. The number of patients aged less than 11 years who had chronic P. aeruginosa infection fell from 23.8% in January 1990 to only 4.3% by December 2000. The annual incidence and mean age of first acquisition of P. aeruginosa did not alter significantly. In conclusion, antipseudomonal management strategies were associated with both reduced prevalence, and an increase in the mean age of onset of chronic P. aeruginosa infection.