Nasal lavage microbiome, but not nasal swab microbiome, correlates with sinonasal inflammation in children with cystic fibrosis.

BACKGROUND: Cystic fibrosis (CF) is characterized by highly viscous mucus obstructing the lower and upper airways, chronic neutrophil inflammation and infection resulting not only in lung destruction but also in paranasal sinus involvement. The pathogenesis of CF-associated chronic rhinosinusitis (CRS) is still not well understood, and it remains unclear how the microbiome in the upper airways (UAW) influences paranasal sinus inflammation. METHODS: In a cross-sectional study in pediatric patients with CF under stable disease conditions, we examined the microbiome in relation to inflammation by comparing nasal swabs (NS) and nasal lavage (NL) as two UAW sampling methods. The microbiota structure of both NS and NL was determined by 16S rRNA gene amplicon sequencing. In addition, pro-inflammatory cytokines (IL-1ß, IL-6, IL-8, TNF-α) and proteases (SLPI, TIMP-1, NE/A1-AT complex) as well as neutrophil elastase activity were measured in NL. RESULTS: Simultaneous NS and NL samples were collected from 36 patients with CF (age range: 7 - 19 years). The microbiome of NS samples was shown to be significantly lower in α-diversity and evenness compared to NL samples. NS samples were particularly found to be colonized with Staphylococcus species. NL microbiome was shown to correlate much better with the sinonasal inflammation status than NS microbiome. Especially the detection of Moraxella in NL was associated with increased inflammatory response. CONCLUSION: Our results show that the NL microbiome reflects sinonasal inflammation better than NS and support NL as a promising tool for simultaneous assessment of the UAW microbiome and inflammation in children with CF.

Reanalysis of N2-lung clearance index and the comparison to SF6-lung clearance index and magnetic resonance imaging.

Since the finding and correction of an error in previous spiroware software versions commonly used with the Exhalyzer D for multiple-breath washout (MBW) analysis, there has been an ongoing discussion about its impact on MBW results. In this study, we reanalyzed previously published findings with the corrected spiroware version 3.3.1. In total, 31 infants and preschool children with cystic fibrosis (CF) (mean age 2.3 ±â€¯0.8 years) and 20 healthy controls (mean age 2.3 ±â€¯1.1 years) underwent consecutive sulfure hexafluoride (SF6)- and nitrogen (N2)-MBW. In addition, children with CF underwent chest magnetic resonance imaging (MRI) on the same day. After reanalysis of MBW data, the corrected N2-lung clearance index (LCI) decreased by 10-15% in both groups (P = 0.001) but remained significantly higher than the SF6-LCI (P<0.01). Diagnostic agreement between the MBW results remained moderate with a persistent correlation between SF6- and N2-MBW. The corrected upper limit of normal of the N2-LCI changed classification of nine children with CF, eight of which were within the normal range after correction. The correlation between the different LCI values and the chest MRI scores remained significant with strongest correlation with the MRI perfusion score. Consequently, the corrected N2-LCI is significantly lower than the previous N2-LCI, but key results published before are not affected by the reanalysis.

Impact of Reanalysis of Nitrogen Multiple-Breath Washout on its Relationship with Chest Magnetic Resonance Imaging Findings in Clinically Stable and Pulmonary Exacerbated Children with Cystic Fibrosis.

RATIONALE: Multiple-breath washout (MBW)-derived lung clearance index (LCI) detects lung disease in children with cystic fibrosis (CF). Correction of a cross-talk error in the software of the MBW device Exhalyzer D in a new software version has generated significant interest regarding its impact on previous MBW findings. Since LCI and chest magnetic resonance imaging (MRI) correlated before in CF children, this study aims to reassess previous MBW data after correction. PATIENTS/METHODS: Reanalysis of the main findings from a previously published study comparing MBW and MRI in a pediatric CF cohort by reassessment of nitrogen (N2) MBW of 61 stable children with CF, 75 age-matched healthy controls (HC), and 15 CF children with pulmonary exacerbation (PEx) in the corrected software version. RESULTS: The corrected LCI (N2LCIcor) decreased in the entire cohort (-17.0 (11.2)%), HC (-8.5 (8.2)%), stable CF children (-22.2 (11.1)%), and within the PEx group at baseline, at PEx and after antibiotic therapy (-21.5 (7.3)%; -22.5 (6.1)%; -21.4 (6.6)%; all P<0.01). N2LCIcor and N2LCIpre correlated with chest MRI scores in stable CF (r=0.70 to 0.84; all P<0.01) without a significant difference between N2LCIcor and N2LCIpre. Change in LCI from baseline to PEx and from PEx to after therapy decreased from N2LCIpre to N2LCIcor, but these changes remained significant (all P=0.001). DISCUSSION/CONCLUSIONS: Our results indicate that N2LCIcor is significantly lower than N2LCIpre, but key results published in the original study demonstrating N2MBW and MRI as complementary methods for clinical surveillance in children with CF remain unaffected.

TRACK-CF prospective cohort study: Understanding early cystic fibrosis lung disease.

Background: Lung disease as major cause for morbidity in patients with cystic fibrosis (CF) starts early in life. Its large phenotypic heterogeneity is partially explained by the genotype but other contributing factors are not well delineated. The close relationship between mucus, inflammation and infection, drives morpho-functional alterations already early in pediatric CF disease, The TRACK-CF cohort has been established to gain insight to disease onset and progression, assessed by lung function testing and imaging to capture morpho-functional changes and to associate these with risk and protective factors, which contribute to the variation of the CF lung disease progression. Methods and design: TRACK-CF is a prospective, longitudinal, observational cohort study following patients with CF from newborn screening or clinical diagnosis throughout childhood. The study protocol includes monthly telephone interviews, quarterly visits with microbiological sampling and multiple-breath washout and as well as a yearly chest magnetic resonance imaging. A parallel biobank has been set up to enable the translation from the deeply phenotyped cohort to the validation of relevant biomarkers. The main goal is to determine influencing factors by the combined analysis of clinical information and biomaterials. Primary endpoints are the lung clearance index by multiple breath washout and semi-quantitative magnetic resonance imaging scores. The frequency of pulmonary exacerbations, infection with pro-inflammatory pathogens and anthropometric data are defined as secondary endpoints. Discussion: This extensive cohort includes children after diagnosis with comprehensive monitoring throughout childhood. The unique composition and the use of validated, sensitive methods with the attached biobank bears the potential to decisively advance the understanding of early CF lung disease. Ethics and trial registration: The study protocol was approved by the Ethics Committees of the University of Heidelberg (approval S-211/2011) and each participating site and is registered at clinicaltrials.gov (NCT02270476).

Increased Inflammatory Markers Detected in Nasal Lavage Correlate with Paranasal Sinus Abnormalities at MRI in Adolescent Patients with Cystic Fibrosis.

Chronic rhinosinusitis (CRS) is a characteristic feature of cystic fibrosis (CF) multiorgan disease and develops early in the life of patients with CF. The study aimed to correlate the inflammatory markers and the presence of structural abnormalities detected by MRI in the paranasal sinuses of patients with CF. Methods: Nasal lavage and MRI of the paranasal sinuses was performed in a cohort of 30 CF patients (median age 14 y; range 7-20 y). Morphological abnormalities characteristic of CF were evaluated with a dedicated CRS MRI scoring system and correlated with different inflammation parameters measured in nasal lavage. Inflammation of the paranasal sinuses was positively associated with structural abnormalities in MRI. The concentration of the pro-inflammatory markers neutrophil elastase (NE) and the neutrophil elastase/alpha1-antitrypsin (NE/A1AT) complex correlated significantly with CRS-MRI sum score (p < 0.05, r = 0.416 and p < 0.05, r = 0.366, respectively). S. aureus infection was associated with the increased pro-inflammatory cytokine activity of IL-6 and IL-8, and increased levels of NE/A1AT complex in our patients (p < 0.05, respectively). CRS-MRI sum score and individual sinus MRI scores were positively associated with inflammatory activity as a sign of CRS pathology present in CF.

Magnetic Resonance Imaging Detects Progression of Lung Disease and Impact of Newborn Screening in Preschool Children with Cystic Fibrosis.

Rationale: Previous cross-sectional studies have demonstrated that chest magnetic resonance imaging (MRI) is sensitive to detect early lung disease in infants and preschool children with cystic fibrosis (CF) without radiation exposure. However, the ability of MRI to detect the progression of lung disease and the impact of early diagnosis in preschool children with CF remains unknown. Objectives: To investigate the potential of MRI to detect progression of early lung disease and impact of early diagnosis by CF newborn screening (NBS) in preschool children with CF. Methods: An annual MRI was performed from diagnosis over 4 years in a cohort of 96 preschool children with CF (age, 0-4 yr) who received concurrent diagnoses on the basis of NBS (n = 28) or clinical symptoms (n = 68). MRI scans were evaluated using a dedicated morphofunctional score, and the relationship between longitudinal MRI score and respiratory symptoms, pulmonary exacerbations, upper airway microbiology, and mode of diagnosis was determined. Measurements and Main Results: The MRI global score increased in the total cohort of children with CF during preschool years (P < 0.001) and was associated with cough, pulmonary exacerbations (P < 0.0001), and the detection of Staphylococcus aureus and Haemophilus influenzae (P < 0.05). MRI-defined abnormalities in lung morphology-especially airway wall thickening/bronchiectasis-were lower in children with CF diagnosed by NBS than in children with clinically diagnosed CF throughout the observation period (P < 0.01). Conclusions: MRI detected progression of early lung disease and benefits of early diagnosis by NBS in preschool children with CF. These findings support MRI as a sensitive outcome measure for diagnostic monitoring and early intervention trials in preschool children with CF. Clinical trial registered with www.clinicaltrials.gov (NCT02270476).

Effects of Lumacaftor-Ivacaftor on Lung Clearance Index, Magnetic Resonance Imaging, and Airway Microbiome in Phe508del Homozygous Patients with Cystic Fibrosis.

Rationale: Previous studies showed that lumacaftor-ivacaftor therapy results in partial rescue of CFTR (cystic fibrosis [CF] transmembrane conductance regulator) activity and a moderate improvement of spirometry in Phe508del homozygous patients with CF. However, the effects of lumacaftor-ivacaftor on lung clearance index (LCI), lung morphology and perfusion detected by chest magnetic resonance imaging (MRI), and effects on the airway microbiome and inflammation remain unknown. Objectives: To investigate the effects of lumacaftor-ivacaftor on LCI, lung MRI scores, and airway microbiome and inflammation. Methods: In this prospective observational study we assessed clinical outcomes including spirometry and body mass index, LCI, lung MRI scores, sputum microbiome, and proinflammatory cytokines in 30 Phe508del homozygous patients with CF 12 years and older before and 8-16 weeks after initiation of lumacaftor-ivacaftor therapy. Results: Lumacaftor-ivacaftor had no effects on forced expiratory volume in 1 second (FEV1% predicted) (1.7%; 95% confidence interval [CI], -1.0% to 4.3%; P = 0.211) but improved LCI (-1.6; 95% CI, -2.6 to -0.5; P < 0.01) and MRI morphology (-1.3; 95% CI, -2.3 to -0.3; P < 0.05) and perfusion score (-1.2; 95% CI, -2.3 to -0.2; P < 0.05) in our study cohort. Furthermore, lumacaftor-ivacaftor decreased the total bacterial load (-1.8; 95% CI, -3.3 to -0.34; P < 0.05) and increased the Shannon diversity of the airway microbiome (0.4; 95% CI, 0.1 to 0.8; P < 0.05), and reduced IL-1ß (interleukin-1ß) concentration (median change, -324.2 pg/ml; 95% CI, -938.7 to 290.4 pg/ml; P < 0.05) in sputum of Phe508del homozygous patients. Conclusions: This study shows that lumacaftor-ivacaftor has beneficial effects on lung ventilation, morphology, and perfusion, as well as on the airway microbiome and inflammation in Phe508del homozygous patients. Our results suggest that LCI and MRI may be more sensitive than FEV1% predicted to detect response to CFTR modulator therapy in patients with chronic CF lung disease. Clinical trial registered with ClinicalTrials.gov (NCT02807415).

Multicentre feasibility of multiple-breath washout in preschool children with cystic fibrosis and other lung diseases.

BACKGROUND: Multiple-breath washout (MBW)-derived lung clearance index (LCI) detects early cystic fibrosis (CF) lung disease. LCI was used as an end-point in single- and multicentre settings at highly experienced MBW centres in preschool children. However, multicentre feasibility of MBW in children aged 2-6 years, including centres naïve to this technique, has not been determined systematically. METHODS: Following central training, 91 standardised nitrogen MBW investigations were performed in 74 awake preschool children (15 controls, 46 with CF, and 13 with other lung diseases), mean age 4.6±0.9 years at investigation, using a commercially available device across five centres in Germany (three experienced, two naïve to the performance in awake preschool children) with central data analysis. Each MBW investigation consisted of several measurements. RESULTS: Overall success rate of MBW investigations was 82.4% ranging from 70.6% to 94.1% across study sites. The number of measurements per investigation was significantly different between sites ranging from 3.7 to 6.2 (p<0.01), while the mean number of successful measurements per investigation was comparable with 2.1 (range, 1.9 to 2.5; p=0.46). In children with CF, the LCI was increased (median 8.2, range, 6.7-15.5) compared to controls (median 7.3, range 6.5-8.3; p<0.01), and comparable to children with other lung diseases (median 7.9, range, 6.6-13.9; p=0.95). CONCLUSION: This study demonstrates that multicentre MBW in awake preschool children is feasible, even in centres previously naïve, with central coordination to assure standardised training, quality control and supervision. Our results support the use of LCI as multicentre end-point in clinical trials in awake preschoolers with CF.

Comparison of lung clearance index determined by washout of N2 and SF6 in infants and preschool children with cystic fibrosis.

BACKGROUND: Multiple-breath washout (MBW) has been shown to detect early impairment of lung function in children with cystic fibrosis (CF). Nitrogen (N2) or sulfur hexafluoride (SF6) can be used as tracer gas for MBW. Recent data indicated higher lung clearance index (LCI) values measured with N2-MBW than concurrent SF6-MBW in older children and adults, however, a comparison in infants and younger children, as well as to other outcome measures of CF lung disease is pending. METHODS: N2- and SF6-MBW were performed consecutively in 31 sedated infants and preschool children with CF (mean age, 2.3 ±â€¯0.8 years) and 20 controls (mean age, 2.3 ±â€¯1.1 years) using the Exhalyzer D system. Children with CF also underwent chest magnetic resonance imaging (MRI). RESULTS: Mean difference (95% CI) in LCI between N2- and SF6-MBW was 1.1 ±â€¯0.4 (0.9 to 1.3) in controls and 2.1 ±â€¯1.9 (1.4 to 2.8) in CF. Agreement between N2- and SF6-LCI was poor in children with CF. N2-LCI and SF6-LCI correlated with MRI, however N2-LCI showed a higher concordance with MRI than SF6-LCI. The absolute difference between N2- and SF6-LCI values increased with the severity of CF lung disease as determined by MRI scores. CONCLUSION: N2-LCI values were higher than SF6-LCI values in infants and preschool children with CF and controls. Better concordance of N2-LCI than SF6-LCI with chest MRI scores point towards of a higher sensitivity of N2-LCI to detect early lung disease in children with CF.

Three-center feasibility of lung clearance index in infants and preschool children with cystic fibrosis and other lung diseases.

BACKGROUND: Lung clearance index (LCI) detects early ventilation inhomogeneity and has been suggested as sensitive endpoint in multicenter intervention trials in infants and preschoolers with cystic fibrosis (CF). However, the feasibility of multicenter LCI in this age group has not been determined. We, therefore, investigated the feasibility of LCI in infants and preschoolers with and without CF in a three-center setting. METHODS: Following central training, standardized SF6-MBW measurements were performed in 73 sedated children (10 controls, 49 with CF and 14 with other lung diseases), mean age 2.3±1.2years across three centers, and data were analyzed centrally. RESULTS: Overall success rate of LCI measurements was 91.8% ranging from 78.9% to 100% across study sites. LCI was increased in patients with CF (P<0.05) and with other lung diseases (P<0.05) compared to controls. CONCLUSION: Our results support feasibility of LCI as multicenter endpoint in clinical trials in infants and preschoolers with CF.

Comparison of Lung Clearance Index and Magnetic Resonance Imaging for Assessment of Lung Disease in Children with Cystic Fibrosis.

RATIONALE: Early onset and progression of lung disease in children with cystic fibrosis (CF) indicates that sensitive noninvasive outcome measures are needed for diagnostic monitoring and early intervention clinical trials. The lung clearance index (LCI) and chest magnetic resonance imaging (MRI) were shown to detect early lung disease in CF; however, the relationship between the two measures remains unknown. OBJECTIVES: To correlate the LCI with abnormalities detected by MRI and compare the sensitivity of the two techniques to detect responses to therapy for pulmonary exacerbations in children with CF. METHODS: LCI determined by age-adapted multiple breath washout techniques and MRI studies were performed in 97 clinically stable children with CF across the pediatric age range (0.2-21.1 yr). Furthermore, LCI (n = 26) or MRI (n = 10) were performed at the time of pulmonary exacerbation and after antibiotic therapy. MRI was evaluated using a dedicated morphofunctional score. MEASUREMENTS AND MAIN RESULTS: The LCI correlated with the global MRI score as well as MRI-defined airway wall abnormalities, mucus plugging, and abnormal lung perfusion in infants and toddlers (P < 0.05 to P < 0.001) and in older children (P < 0.001) with CF. LCI and MRI were sensitive to detect response to antibiotic therapy for pulmonary exacerbations. CONCLUSIONS: Our results indicate that LCI and MRI may be useful complementary tools for noninvasive monitoring and as quantitative endpoints in early intervention trials in children with CF. In this context, MRI enables detection of disease heterogeneity, including regional mucus plugging associated with abnormal lung perfusion in early CF lung disease. Clinical trial registered with www.clinicaltrials.gov (NCT 02270476).

Supplementation with red palm oil increases ß-carotene and vitamin A blood levels in patients with cystic fibrosis.

Patients with cystic fibrosis (CF) show decreased plasma concentrations of antioxidants due to malabsorption of lipid soluble vitamins and consumption by chronic pulmonary inflammation. ß-Carotene is a major source of retinol and therefore is of particular significance in CF. The aim of this study was to investigate the effect of daily intake of red palm oil (RPO) containing high amounts of ß-carotene on the antioxidant levels in CF patients. Sixteen subjects were recruited and instructed to enrich their food with 2 to 3 tablespoons of RPO (~1.5 mg of ß-carotene) daily over 8 weeks. Carotenoids, retinol, and α-tocopherol were measured in plasma at baseline and after intervention. In addition ß-carotene, lycopene, α-tocopherol, and vitamin C were measured in buccal mucosa cells (BMC) to determine the influence of RPO on antioxidant tissue levels. Eleven subjects completed the study properly. Plasma ß-carotene, retinol, and α-carotene of these patients increased, but plasma concentrations of other carotenoids and α-tocopherol as well as concentrations of ß-carotene, lycopene, α-tocopherol, and vitamin C in BMC remained unchanged. Since RPO on a daily basis did not show negative side effects the data suggest that RPO may be used to elevate plasma ß-carotene in CF.

Multiple breath washout is feasible in the clinical setting and detects abnormal lung function in infants and young children with cystic fibrosis.

BACKGROUND: Cystic fibrosis (CF) lung disease starts in the first months of life often before the onset of clinical symptoms. Multiple breath washout (MBW) detects abnormal lung function in infants and young children in the laboratory setting. OBJECTIVE: The aim of this study was to determine the feasibility of MBW in 0- to 4-year-old children with CF and non-CF controls in the clinical setting. METHODS: Fourteen children with CF (mean age 1.3 ± 1.0 years) and 26 age-matched non-CF controls were sedated with chloral hydrate and MBW was performed with sulfur hexafluoride. RESULTS: MBW measurements were successful in 27 of 40 children (67.5%). The mean lung clearance index (LCI) was significantly higher in CF patients compared to non-CF controls (p = 0.006). Further, the frequency of elevated LCI (z-score >1.96) was significantly increased in CF patients compared to controls (p = 0.0003). CONCLUSIONS: We conclude that MBW is feasible and sensitive to detect abnormal lung function in infants and young children with CF in the clinical setting.