100 Comparison of airway microbiota composition in healthy children and children with CF

Abstract

Introduction and Aims: Although a number of studies have characterized airway microbiota composition in healthy and CF adult populations, limited data is available for the paediatric population. The aim of this study was to define, using culture based methods, the composition of the airway microbiota in age-matched healthy and CF paediatric groups. Methods: Induced sputum samples (CF) and cough swabs (CF, age-matched healthy volunteers) were collected and processed using both aerobic and strict anaerobic bacteriological culture techniques. Bacteria within the samples were detected by plating on selective agars and identified by PCR and sequencing of 16S ribosomal RNA genes. Results: Samples were collected from 21 healthy volunteers (mean (SD) age 11.0 (3.5) yrs; 13M:8F) and from 12 children with CF (mean (SD) age 12.8 (3.2) yrs; 6M:6F) when clinically stable. Bacteria were detected in all samples from CF patients and in 18/21 (86%) healthy volunteers. Aerobic bacteria from genera including Streptococcus, Staphylococcus, Pseudomonas and Haemophilus were detected in both cohorts with Pseudomonas [CF, n = 2/12 (17%); control, n = 1/21 (5%)] and Haemophilus [CF, n = 7/12 (58%); control n = 4/21 (19%)] present in a greater number of CF patients compared to controls. Anaerobic bacteria from genera including Prevotella, Veillonella, and Actinomyces were detected in both cohorts. Conclusion: Aerobic and anaerobic bacteria have been detected by culture in the lungs of children with CF and healthy children. Pseudomonas and Haemophilus, recognised as pathogens in CF patients, were more prevalent in CF patients compared to controls. Funded by US-Ireland Project Partnership Grant.