Inflammatory Responses to Individual Microorganisms in the Lungs of Children With Cystic Fibrosis

Abstract

Pulmonary infection with P. aeruginosa, S. aureus, or Aspergillus species and growth of MOF was associated with significant inflammatory responses in young children with CF. Our data support the use of specific surveillance and eradication programs for these organisms. The inflammatory response to MOF requires additional investigation.

Impact of lung disease on respiratory impedance in young children with cystic fibrosis

“…In addition, BRUMBACK et al [42] found that recent H. influenzae infection was associated with lower forced vital capacity in preschool children with CF. Infection with H. influenzae has also been associated with pulmonary inflammation [14,31] and pulmonary exacerbations [43] in children with CF. These data indicate that H. influenzae is highly pathogenic in young children with CF, and should be targeted for eradication and treatment to improve lung function outcomes.…”

“…The right middle lobe was lavaged with three aliquots of saline (1 mL·kg −1 body weight) and an additional aliquot lavaged into the lingula or the most affected lobe identified on CT [1,31]. The first aliquot of BAL fluid was processed for the detection of bacteria, viruses and fungi using standard culture techniques.…”

“…An infection with a bacterial or fungal load of ⩾10 5 cfu·mL −1 (excluding mixed oral flora) was considered significant. Bacterial pathogens known to elicit a pro-inflammatory response when isolated from the lower respiratory tract (P. aeruginosa, Staphylococcus aureus, Haemophilus influenzae, Streptococcus pneumoniae and Aspergillus species) were described as pro-inflammatory pathogens [31]. Subsequent aliquots were pooled for the quantification of pulmonary inflammation which included total and differential cell counts, interleukin (IL)-8 and measurement of free neutrophil elastase activity (lower limit of detection 200 ng·mL…”

Risk Factors for Bronchiectasis in Children With Cystic Fibrosis

“…4 Pulmonary infection was determined as previously described, 16 with infection defined as a colony count for a specific organism (excluding mixed oral flora) of 10 5 colony-forming units per milliliter or more. In the case of P. aeruginosa, however, the criterion for infection was the presence of the organism in any density in BAL cultures.…”

Early lung surveillance of cystic fibrosis: what have we learnt?

“…Furthermore, while Staphylococcus aureus, Haemophilus influenzae, Aspergillus species, and Pseudomonas aeruginosa have been linked to increased inflammatory indicators in BAL [9], data from AREST CF have also clearly emphasized that a significant number of children with CF have detectable inflammation in the absence of overt infection detected using standard microbiological techniques [10]. More sensitive metagenomic approaches that improve quantification of bacteria and viruses in BAL, combined with more detailed neutrophil characterization [11], will provide insight into initial pathogen exposures and the development of chronic neutrophilic inflammation in the CF airways.…”