Clinical characteristics of people with cystic fibrosis and frequent fungal infection.

BACKGROUND: Individuals with cystic fibrosis (CF) and fungal airway infection may present with fungal bronchitis, allergic bronchopulmonary aspergillosis (ABPA) or may appear unaffected despite fungal detection. We sought to characterize people with CF with frequent detection of fungi from airway samples and determine clinical outcomes. METHODS: This retrospective study included individuals with CF with ≥4 lower airway cultures over a 2-year baseline period and ≥2 years of follow-up. We defined two groups: ≤1 positive fungus culture (rare) or ≥2 positive cultures during baseline (frequent). Clinical characteristics and outcomes were determined. RESULTS: Between 2004 and 2016, 294 individuals met inclusion with 62% classified as rare and 38% as frequent fungi during baseline. Median follow-up was 6 years (range: 2-9 years). Aspergillus fumigatus was the most common fungal species detected. Individuals with frequent fungi were older (13.7 vs. 11.7 years, p = .02) and more likely to have Stenotrophomonas maltophilia (35% vs. 17%, p < .001) at baseline, but did not differ in lung function or ABPA diagnosis. During follow-up, those with frequent fungi were more likely to have chronic Pseudomonas aeruginosa and S. maltophilia. Individuals with ABPA and frequent fungi had the highest rates of co-infection and co-morbidities, and a trend towards more rapid lung function decline. DISCUSSION: Fungal infection in CF was associated with frequent P. aeruginosa and S. maltophilia co-infection even in those without ABPA. Individuals with frequent fungi and ABPA had worse outcomes, highlighting the potential contribution of fungi to CF pulmonary disease.

Detection of bacterial pathogens using home oropharyngeal swab collection in children with cystic fibrosis.

BACKGROUND: Collection of respiratory cultures for airway microbiology surveillance is an essential component of routine clinical care in cystic fibrosis (CF). The COVID-19 global pandemic has necessitated increased use of telehealth, but one limitation of telehealth is the inability to collect respiratory specimens. We initiated a protocol for at-home collection of oropharyngeal (OP) swabs from children with CF. METHODS: Home respiratory specimen collection was offered during telehealth encounters. Home OP swab kits were sent to participating families via mail with instructions for collection and return. Specimens were returned by overnight shipping or dropped off at a hospital lab for processing and culture. We evaluated demographic data and compared culture results from the home-collected specimen to the most recent specimen collected in clinic. We also tracked the frequency of newly identified Pseudomonas aeruginosa. RESULTS: Home OP swab kits were sent to families of 33 children with CF (range 1.5-19 years). OP swab kits were successfully returned from 19 children (range 1.5-19 years). One or more CF pathogens grew from 79% of the specimens. For four individuals, the home collected specimen demonstrated the new growth of P. aeruginosa. CONCLUSIONS: Home collection of OP swabs for bacterial culture is feasible in children with CF across a range of ages. Most home-collected specimens demonstrated growth of one or more CF pathogens and results were similar to recent in-clinic specimens, suggesting acceptable sample collection technique. Anti-pseudomonal therapy was initiated for four children based on the growth of P. aeruginosa from the home respiratory specimen.

Sputum induction improves detection of pathogens in children with cystic fibrosis.

BACKGROUND: Sputum induction is a safe, well tolerated means of obtaining lower airway secretions from children with cystic fibrosis (CF), particularly for assessment of airway inflammation but the clinical value in diagnosing outpatient infections has not been extensively studied. OBJECTIVES: Investigate the success rate and microbiologic yield of induced sputum (IS) compared to oropharyngeal swabs (OP) and expectorated sputum (ES) samples in children with CF, and determine if IS culture results impact treatment. METHODS: Two cohorts were included in this prospective, longitudinal comparative study. In one cohort, simultaneously collected OP, ES, and IS specimens were obtained from 17 CF children at three visits over 1 year. In the second group, sputum induction was performed in 35 CF subjects at four annual visits, and culture results were compared to their nearest respiratory culture within 4 months. Antimicrobial treatment regimens were captured retrospectively. RESULTS: Sputum induction was successful in 149 of 158 (94%) visit encounters. Polymicrobial infection (combined P = 0.005) and gram negative organisms (combined P = 0.003) were detected more frequently in IS samples compared to OP, as were the individual pathogens Pseudomonas aeruginosa (combined P = 0.04) and Stenotrophomonas maltophilia (combined P = 0.05). The microbiologic yield of serial IS samples collected over 1 year was stable. IS culture results led to antibiotic changes in 6% of visit encounters. However, based on current practice 13% of visits could have resulted in treatment changes. CONCLUSIONS: Sputum induction is feasible in the outpatient setting and appears to improve pathogen detection in children with CF.