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Background: Person-to-person transmission is a potential pathway of Pseudomonas aeruginosa acquisition in cystic fibrosis. Reports of cross-infection of shared cystic-fibrosis-specific P aeruginosa strains across large geographical distances are concerning. Therefore, we aimed to assess the extent to which patient movement between cystic fibrosis centres contributes to dissemination. Method(s): We did a cross-sectional study to assess movement of patients with cystic fibrosis who were infected with P aeruginosa between Sept 3, 2007, and June 16, 2010, at 18 Australian cystic fibrosis centres. We applied social network analysis to patient movement data from P aeruginosa-infected patients to assess the role of patient mobility in P aeruginosa genotype prevalence. We generated networks linking treatment centres based on the movement of patients attending adult and paediatric cystic fibrosis centres, and compared these with the movement of patients infected with all P aeruginosa strains, unique strains, and predominant Australian shared strains (AUST-01 and AUST-02). We summarised connectivity using degree centrality, in-degree centrality, out-degree centrality, and k-core estimates. Infection control and surveillance practices were also assessed by use of a questionnaire. Finding(s): 983 patients (mean age 25 years [SD 10]; 551 [56%] male) provided 2887 P aeruginosa isolates for ERIC-PCR genotyping, which yielded 531 distinct genotypes: 493 unique strains in 373 patients and 38 shared strains in 610 patients. AUST-01 infections were associated with higher in-degree centrality (p=0.004) and k-core (p=0.005) estimates and AUST-02 infections with higher degree centrality (p=0.002), out-degree centrality (p=0.002), and k-core (p=0.007) estimates for the previous health-care facilities; associations for the present cystic fibrosis centre were not significant. These findings were significant for adult patients (AUST-01 in-degree centrality p=0.004 and k-core p=0.005; AUST-02

Recent molecular-typing studies suggest cross-infection as one of the potential acquisition pathways for Pseudomonas aeruginosa in patients with cystic fibrosis (CF). In Australia, there is only limited evidence of unrelated patients sharing indistinguishable P. aeruginosa strains. We therefore examined the point-prevalence, distribution, diversity and clinical impact of P. aeruginosa strains in Australian CF patients nationally. 983 patients attending 18 Australian CF centres provided 2887 sputum P. aeruginosa isolates for genotyping by enterobacterial repetitive intergenic consensus-PCR assays with confirmation by multilocus sequence typing. Demographic and clinical details were recorded for each participant. Overall, 610 (62%) patients harboured at least one of 38 shared genotypes. Most shared strains were in small patient clusters from a limited number of centres. However, the two predominant genotypes, AUST-01 and AUST-02, were widely dispersed, being detected in 220 (22%) and 173 (18%) patients attending 17 and 16 centres, respectively. AUST-01 was associated with significantly greater treatment requirements than unique P. aeruginosa strains. Multiple clusters of shared P. aeruginosa strains are common in Australian CF centres. At least one of the predominant and widespread genotypes is associated with increased healthcare utilisation. Longitudinal studies are now needed to determine the infection control implications of these findings. Copyright ©ERS 2013.

Objective: Our aim was to determine the safety of BAL in young children <6 years with CF. Method(s): As part of a multi-center study of BAL-directed therapy, children with CF <6 years had one or more BALs between September 1999 and December 2005. Adverse events were recorded intraoperatively and for 24 hr thereafter. Clinical characteristics before BAL, findings at bronchoscopy and BAL results were assessed as risk factors for adverse events. Result(s): 333 BALs were conducted in 107 (56 males) children, median age 23.5 (range 1.6-67.5) months, including 170 (51%) for pulmonary exacerbation. 29 BALs (8.7%) were followed by fever >=38.5degreeC and 10 (3%) had clinically significant episodes (five intraoperative hemoglobin desaturations to <90% requiring intervention, one tachyarrhythmia, two needing post-operative supplemental oxygen, one hospitalization for stridor). Two contaminated bronchoscopes were detected. 180 minor adverse events were recorded in 174 (52%) BAL procedures (137 altered cough, 41 fever <38.5degreeC). Low percentage BAL return (P = 0.002) and focal bronchitis (P = 0.02) were associated with clinically significant deterioration. Multivariable analysis identified Streptococcus pneumoniae (OR 22.3; 95% confidence interval (CI); 6.9,72), Pseudomonas aeruginosa (OR 2.4; 95% CI 1.0, 5.8), respiratory signs (OR 5.0; 95% CI 1.7, 14.6) and focal bronchitis (OR 5.9; 95% CI 1.2, 29.8) as independent risk factors for post-bronchoscopy fever >=38.5degreeC. Conclusion(s): Adverse events are common with BAL in young CF children, but are usually transient and well tolerated. Parents should be counseled that signs of a pre-existing lower respiratory infection are associated with increased risk of post-BAL fever. © 2008 Wiley-Liss, Inc.