NEW YORK (Reuters Health) – In infants and young children with cystic fibrosis, treating Pseudomonas aeruginosa infection based on bronchoalveolar lavage (BAL) rather than oropharyngeal cultures does not improve outcomes, according to an Australasian study.
“BAL-directed therapy did not reduce structural lung abnormalities seen on high-resolution chest CT scans or prevalence of P aeruginosa infection at age 5 years when compared with standard treatment,” the researchers report in the Journal of the American Medical Association for July 13.
Dr. Claire E. Wainwright, with the Royal Children’s Hospital in Brisbane, Queensland, Australia, and colleagues note that prompt treatment of P aeruginosa infection in CF patients often leads to eradication, but once established the infection can rarely be eliminated. Treatment is often based on oropharyngeal culture but its accuracy is questionable, so the team investigated the safety and utility of BAL as an alternative diagnostic tool in a prospective study of infants diagnosed with cystic fibrosis on newborn screening.
The infants were randomly assigned to receive BAL-directed therapy or standard therapy based on clinical features and oropharyngeal cultures up to age 5. “The BAL-directed therapy group underwent BAL before age 6 months when well, when hospitalized for pulmonary exacerbations, if Pseudomonas aeruginosa was detected in oropharyngeal specimens, and after P aeruginosa eradication therapy,” according to the report.
Ultimately, 79 children in the BAL group and 76 in the standard group completed the study. The researchers found the 10% and 12% in the two groups respectively had P aeruginosa in final BAL cultures at age 5 – a nonsignificant difference (p=0.73).
Structural lung abnormality scores based on CT assessment were also not significantly different between the two groups at 3.0% and 2.8% (p=0.74). Furthermore, the incidence of exacerbations during the study was 3.68 per person-year in the BAL-directed arm compared with 3.65 per person-year in the standard therapy arm.
In clinical practice, Dr. Wainwright and colleagues conclude, “BAL is perhaps best reserved for young children whose conditions are deteriorating despite parenteral antibiotic therapy; when unusual or antibiotic-resistant pathogens, including clonal P aeruginosa strains, are suspected; and to diagnose patients with chronic P aeruginosa infection.”