Search

This report describes the characterization of Burkholderia cenocepacia isolates belonging to sequence type (ST)-250, detected in eight patients with cystic fibrosis (CF) in Switzerland. We retrospectively analyzed 18 isolates of B. cenocepacia ST-250 isolated between 2003 and 2015 by whole-genome sequencing and evaluated clinical and epidemiological data. Single nucleotide polymorphism analysis of the B.°cenocepacia ST-250 lineage showed that the isolates from all patients cluster tightly, suggesting that this cluster has a recent common ancestor. Epidemiological investigations showed that six out of eight patients acquired B.°cenocepacia ST-250 in the years 2001-2006, where participation in CF summer camps was common. Two patients were siblings. Genomic relatedness of the B. cenocepacia ST-250 isolates supported transmission by close contact, however, a common source or nosocomial routes cannot be excluded. With respect to the fatal outcome in six patients, our study shows the importance of infection control measurements in CF patients with B.°cenocepacia., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Background: Non-invasive and sensitive clinical endpoints are needed to monitor onset and progression of early lung disease in children with cystic fibrosis (CF). We compared lung clearance index (LCI), FEV 1 , functional and structural lung magnetic resonance imaging (MRI) outcomes in Swiss children with CF diagnosed following newborn screening., Methods: Lung function (LCI, FEV 1 ) and unsedated functional and structural lung MRI was performed in 79 clinically stable children with CF (3 - 8 years) and 75 age-matched healthy controls. Clinical information was collected throughout childhood., Results: LCI, ventilation and perfusion defects, and structural MRI scores were significantly higher in children with CF compared with controls, but FEV 1 was not different between groups. Lung MRI outcomes correlated significantly with LCI (morphology score (r = 0.56, p < 0.001); ventilation defects (r = 0.43, p = 0.001); perfusion defects (r = 0.64, p < 0.001), but not with FEV 1 . Lung MRI outcomes were more sensitive to detect impairments in children with CF (abnormal ventilation and perfusion outcomes in 47 %, morphology score in 30 %) compared with lung function (abnormal LCI in 21 % and FEV 1 in 4.8 %). Pulmonary exacerbations, respiratory hospitalizations, and increase in patient-reported cough was associated with higher LCI and higher structural and functional MRI outcomes., Conclusions: The LCI and lung MRI outcomes non-invasively detect even mild early lung disease in young children with CF diagnosed following newborn screening. Pulmonary exacerbations and early respiratory symptoms were risk factors for structural and functional impairment in childhood., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Prof. P. Latzin reports the followind COIs: - Grants from Vertex and OM Pharma paid to the institution - Participation on data safety monitoring boards or advisory boards of Polyphor, Santhera DMC, Vertex, OM Pharma, Vifor, Sanofi Aventis - Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: Vertex, Vifor, OM Pharma Jakob Usemann reports: Grants from - Swiss lung foundation - Palatin Foundation, Basel, Switzerland Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: - Vertex - Zurich Lung foundation Support for attending meetings and/or travel from Vertex Kathryn Ramsey reports: Support for the present manuscript form: -Swiss National Science Foundation Ambizione Research Grant (168173), paid to the institution Leadership or fiduciary role in other board, society, committee or advocacy group, unpaid Global Lung Initiative MBW Task Force Elisabeth Kieninger reports: Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events: Sanofi-Aventis., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Inhalation of hypertonic saline (HS) is standard of care in patients with cystic fibrosis (CF). However, it is unclear if adding salbutamol has-besides bronchodilation-further benefits, for example, on the mucociliary clearance. We assessed this in vitro by measuring the ciliary beating frequency (CBF) and the mucociliary transport rate (MCT) in nasal epithelial cells (NECs) of healthy volunteers and patients with CF. Aims: To investigate the effect of HS, salbutamol, and its combination on (muco)ciliary activity of NECs in vitro , and to assess potential differences between healthy controls and patients with CF. Methods: NECs obtained from 10 healthy volunteers and 5 patients with CF were differentiated at the air-liquid interface and aerosolized with 0.9% isotonic saline ([IS] control), 6% HS, 0.06% salbutamol, or combined HS and salbutamol. CBF and MCT were monitored over 48-72 hours. Results: In NECs of healthy controls, the absolute CBF increase was comparable for all substances, but CBF dynamics were different: HS increased CBF slowly and its effect lasted for an extended period, salbutamol and IS increased CBF rapidly and the effect subsided similarly fast, and HS and salbutamol resulted in a rapid and long-lasting CBF increase. Results for CF cells were comparable, but less pronounced. Similar to CBF, MCT increased after the application of all the tested substances. Conclusion: CBF and MCT of NECs of healthy participants and CBF of patients with CF increased upon treatment with aerosolized IS, HS, salbutamol, or HS and salbutamol, showing a relevant effect for all tested substances. The difference in the CBF dynamics can be explained by the fact that the properties of the mucus are changed differently by different saline concentrations.

Background: With improvement in supportive therapies and the introduction of cystic fibrosis transmembrane conductance regulator (CFTR)-modulator treatment in patients with cystic fibrosis (CF), milder disease courses are expected. Therefore, sensitive parameters are needed to monitor disease course and effects of CFTR-modulators. Functional lung MRI using matrix-pencil decomposition (MP-MRI) is a promising tool for assessing ventilation and perfusion quantitatively. This study aimed to assess the treatment effect of elexacaftor/tezacaftor/ivacaftor combination regimen (ELX/TEZ/IVA) on measures of structural and functional lung abnormalities., Methods: 24 children with CF underwent lung function tests (multiple breath washout, spirometry), functional and structural MRI twice (one year apart) before and once after at least two weeks (mean 4.7 ± 2.6 months) on ELX/TEZ/IVA. Main outcomes were changes (Δ) upon ELX/TEZ/IVA in lung function, defect percentage of ventilation (VDP) and perfusion (QDP), defect distribution index of ventilation and perfusion (DDI V, DDI Q ), and Eichinger score. Statistical analyses were performed using paired t-tests and multilevel regression models with bootstrapping., Results: We observed a significant improvement in lung function, structural and functional MRI parameters upon ELX/TEZ/IVA treatment (mean; 95%-CI): ΔLCI 2.5 (TO) -0.84 (-1.62 to -0.06); ΔFEV 1 (z-score) 1.05 (0.56 to 1.55); ΔVDP (% of impairment) -6.00 (-8.44 to -3.55); ΔQDP (% of impairment) -3.90 (-5.90 to -1.90); ΔDDI V -1.38 (-2.22 to -0.53); ΔDDI Q -0.31 (-0.73 to 0.12); ΔEichinger score -3.89 (-5.05 to -2.72)., Conclusions: Besides lung function tests, functional and structural MRI is a suitable tool to monitor treatment response of ELX/TEZ/IVA therapy, and seems promising as outcome marker in the future., (Copyright © 2022. Published by Elsevier B.V.)

Rationale: The lung clearance index (LCI) is increasingly being used in the clinical surveillance of patients with cystic fibrosis (CF). However, there are limited data on long-term variability and physiologically relevant changes in LCI during routine clinical surveillance., Objectives: To evaluate the long-term variability of LCI and propose a threshold for a physiologically relevant change., Methods: In children aged 4-18 years with CF, LCI was measured every 3 months as part of routine clinical surveillance during 2011-2020 in two centers. The variability of LCI during periods of clinical stability was assessed using mixed-effects models and was used to identify thresholds for physiologically relevant changes., Results: Repeated LCI measurements of acceptable quality (N = 858) were available in 100 patients with CF; for 74 patients, 399 visits at clinical stability were available. The variability of repeated LCI measurements over time expressed as the coefficient of variation (CV%) was 7.4%. The upper limit of normal (ULN) for relative changes in LCI between visits was 19%., Conclusion: We report the variability of LCI in children and adolescents with CF during routine clinical surveillance. According to our data, a change in LCI beyond 19% may be considered physiologically relevant. These findings will help guide clinical decisions according to LCI changes., (© 2022 Wiley Periodicals LLC.)

Background: Inhalation therapy is one of the cornerstones of the daily treatment regimen in patients with cystic fibrosis (CF). Recommendations regarding the addition of bronchodilators, especially salbutamol are conflicting due to the lack of evidence. New diagnostic measures such as multiple-breath washout (MBW) and functional magnetic resonance imaging (MRI) have the potential to reveal new insights into bronchodilator effects in patients with CF., Objective: The objective of the study was to comprehensively assess the functional response to nebulized inhalation with salbutamol in children with CF., Methods: Thirty children aged 6-18 years with stable CF performed pulmonary function tests, MBW, and matrix pencil-MRI before and after standardized nebulized inhalation of salbutamol., Results: Lung clearance index decreased (improved) by -0.24 turnover (95% confidence interval [CI]: -0.53 to 0.06; p = 0.111). Percentage of the lung volume with impaired fractional ventilation and relative perfusion decreased (improved) by -0.79% (CI: -1.99 to 0.42; p = 0.194) and -1.31% (CI: -2.28 to -0.35; p = 0.009), respectively. Forced expiratory volume (FEV1) increased (improved) by 0.41 z-score (CI: 0.24-0.58; p < 0.0001). We could not identify specific clinical factors associated with a more pronounced effect of salbutamol., Conclusions: There is a positive short-term effect of bronchodilator inhalation on FEV1 in patients with CF, which is independent of ventilation inhomogeneity. Heterogeneous response between patients suggests that for prediction of a therapeutic effect this should be tested by spirometry in every patient individually., (© 2021 S. Karger AG, Basel.)

Background: Lung disease can develop within the first year of life in infants with cystic fibrosis (CF). However, the frequency and severity of respiratory symptoms in infancy are not known., Methods: We assessed respiratory symptoms in 50 infants with CF and 50 healthy matched controls from two prospective birth cohort studies. Respiratory symptoms and respiratory rate were documented by standardized weekly interviews throughout the first year. Infants performed multiple breath washout in the first weeks of life., Results: We analyzed 4552 data points (2217 in CF). Respiratory symptoms (either mild or severe) were not more frequent in infants with CF (OR:1.1;95% CI:[0.76, 1.59]; p=0.6). Higher lung clearance index and higher respiratory rate in infants with CF were not associated with respiratory symptoms., Conclusions: We found no difference in respiratory symptoms between healthy and CF infants. These data indicate that early CF lung disease may not be captured by clinical presentation alone., Competing Interests: Declaration of Competing Interest Dr. Latzin reports personal fees from Gilead, personal fees from Novartis, OM Pharma, Polyphor, Roche, Santhera, Schwabe, Vertex, Vifor, Zambon and grants from Vertex, outside the submitted work., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Chronic lung diseases such as cystic fibrosis (CF) can be monitored by imaging and lung function modalities. Magnetic resonance imaging (MRI) techniques such as matrix pencil (MP) decomposition allows for evaluation of regional impairment of fractional ventilation (R FV ) and relative perfusion (R Q ). However, reproducibility of MP MRI outcomes in children with CF is unknown. We examined short-term variability of ventilation and perfusion impairment from MP MRI and compared this to lung function outcomes., Method: Twenty-threeCF and 12 healthy school-aged children underwent MRI and lung function tests on the same day on two occasions 24 h apart. Global ventilation inhomogeneity was assessed by the lung clearance index (LCI) from nitrogen-multiple breath washout (N 2 -MBW) technique. Intra-class-coefficient (ICC), percentage change, and Bland-Altman limits of agreement were evaluated to assess reproducibility., Results: Sixty-nine measurements from MP MRI and N 2 -MBW were performed. The ICC between two visits for R FV , R Q and LCI ranged between 0.60 and 0.90 in individuals with CF and healthy controls. In individuals with CF, percentage of change between the visits was 0.02% for R FV , -1.11% for R Q and 2.91% for LCI and limits of agreement between visits were - 4.3% and 3.9% for R FV , -4.4% and 3.7% for R Q , and -2.6 and 3.0 for LCI., Conclusions: Functional imaging is reproducible and short-term changes in R FV and R Q greater than ±4.4% can be considered clinical meaningful. Very good short-term reproducibility, and easy application without the need for breathing maneuvers or contrast agent, makes MP MRI a promising surveillance method for CF., (Copyright © 2018 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Objectives: In the national newborn screening programme for CF in Switzerland, we compared the performance of two sweat test methods, by investigating the feasibility and diagnostic performance of the Macroduct ® collection method (with chloride mesurement) and Nanoduct ® test (measuring conductivity) for diagnosing CF., Study-Design: We included all newborns with a positive screening result between 2011 and 2015 who were referred to a CF-centre for sweat testing. In the CF-centre, a Macroduct and Nanoduct sweat test were performed simultaneously. If sweat test results were positive or borderline, a DNA analysis was performed. Final diagnosis was based on genetic mutations., Results: Over 5 years, 445 children were screened positive and in 413 (114 with CF) at least one sweat test was performed (median age at first test, 22 days); both tests were performed in 371 children. A sweat test result was more often available with the Nanoduct compared to the Macroduct (79 vs 60%, P < 0.001). The Nanoduct was equally sensitive as the Macroduct in identifying newborns with CF (sensitivity 98 vs 99%) but less specific (specificity 79 vs 93%; P-value comparing ROC curves = 0.033)., Conclusions: This national multicentre study revealed high failure rates for Macroduct and Nanoduct in newborns in real life practice. While this needs to be addressed, our results suggested that performing the Nanoduct in addition to the Macroduct might speed up the diagnostic process because it more often yields valid results with comparable diagnostic performance. The addition of the Nanoduct sweat test can therefore help to reduce the stressful time of uncertainty for parents and to start appropriate treatment earlier., (© 2019 Wiley Periodicals, Inc.)

Background: Lung impairment in cystic fibrosis (CF) starts in infancy. However, tools to monitor early lung disease are limited. Respiratory rate (RR) as a key vital sign is easy to assess during sleep and is elevated during acute respiratory disease. Thus, elevated RR could indicate early lung impairment and potentially serve as a diagnostic tool in disease monitoring., Methods: In a prospective cohort of infants with CF diagnosed by newborn screening and healthy controls RR was measured and respiratory symptoms reported weekly throughout infancy. Infants performed a lung function measurement within the first weeks of life., Results: The analyses included 5656 measurements from 153 infants (43 with CF). RR declined from 43.2 (40.5)/min at 6 weeks of age to 28.3 (24.6)/min at 50 weeks in infants with CF (healthy controls). Infants with CF had consistently higher RR than controls (mean difference: 4.15/min; (95% CI 2.86-5.44); p < .001). In both study groups, RR was increased throughout the study period in infants with higher lung clearance indices (LCI) and during episodes of respiratory infections., Conclusions: Infants with CF have a higher RR compared to healthy controls during the first year of life. The association with early LCI measurements, the current gold standard to assess physiology of peripheral airways persisted throughout the study period. This may indicate tracking of lung function by RR. It might thus be an early subtle sign of functional respiratory deficit. Further studies will show if RR can be used as a sensitive and promising marker to monitor early CF lung disease., (Copyright © 2018 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Introduction: Normalized phase III slope (Sn III ) indices from multiple breath washout (MBW) estimate ventilation inhomogeneity. Alternate (*) protocols for Sn III indices exist, however the utility of these outcomes in children with mild-to-moderate cystic fibrosis (CF) is unknown., Methods: We measured nitrogen MBW and spirometry in 135 children (43 controls) aged 4-18 years. We assessed validity, practicability, and reliability of Sn III protocols. Outcomes included the ability to detect abnormal lung function, test agreement, measurement duration, intra-test repeatability, and quality., Results: Lung clearance index (LCI) was abnormal in 80 (87%), Scond in 55 (60%), Scond* in 17 (19%), Sacin in 10 (11%), Sacin* in 11 (12%), and FEV 1 in 28 (30%). Alternate protocols reduced measurement duration. Agreement of indices to detect abnormal lung function was poor. The quality of analysis and repeatability deteriorated with the alternate technique compared to standard., Conclusion: In children with mild-to-moderate CF lung disease, alternate protocols seem practical but clinimetric properties of standard Sn III protocols are preferable., (© 2018 Wiley Periodicals, Inc.)

The Swiss Cystic Fibrosis Infant Lung Development (SCILD) cohort is a prospective birth cohort study investigating the initiating events of cystic fibrosis lung disease during infancy, and their influence on the trajectory of disease progression throughout early childhood. Infants with cystic fibrosis are recruited throughout Switzerland after diagnosis by new-born screening. It is the first European population-based prospective cohort study of infants with cystic fibrosis taking advantage of a nationwide new-born screening programme. The study was established in 2011 and recruitment is ongoing. The cohort study is currently divided into three study phases (phase 1: diagnosis to age 1 year; phase 2: age 1 to 3 years; and phase 3: age 3 to 6 years). Study participants have weekly telephone interviews, weekly anterior nasal swab collection and two study visits in the first year of life. They also complete follow-up study visits at 3 and 6 years of age. Data for this study are derived from questionnaires, lung function measurements, telephone interviews, nasal swab material and magnetic resonance imaging. To date, 70 infants have been recruited into the study and 56 have completed phase 1, including a baseline study visit at 6 weeks of age, weekly surveillance and a study visit at one year of age. More than 2500 data points on respiratory health and almost 2000 nasal samples have been collected. Phases 2 and 3 will commence in 2018. The dataset of the SCILD cohort combines lung function data, the collection of environmental and sociodemographic factors, documentation of respiratory symptoms, and microbiological analyses. The design not only allows tracking of the cystic fibrosis lung disease independent of clinical status, but also surveillance of early disease prior to severe clinical symptoms. This cohort profile provides details on the study design and summarizes the first published results of the SCILD cohort.

Rationale: Acute viral respiratory tract infections in children with cystic fibrosis (CF) are known causes of disease exacerbation. The role of viral infections during infancy is, however, less known, although early infancy is thought to be a crucial period for CF disease development.We prospectively assessed symptomatic and asymptomatic viral detection in the first year of life in infants with CF and healthy controls., Methods: In a prospective cohort study, we included 31 infants with CF from the Swiss Cystic Fibrosis Infant Lung Development Cohort and 32 unselected, healthy infants from the Basel Bern Infant Lung Development Cohort and followed them throughout the first year of life. Respiratory symptoms were assessed by weekly telephone interviews. Biweekly nasal swabs were analysed for 10 different viruses and two atypical bacteria with real-time seven duplex PCR (CF=561, controls=712)., Measurements and Results: Infants with CF and healthy controls showed similar numbers of swabs positive for virus (mean 42% vs 44%; OR 0.91, 95% CI 0.66 to 1.26, p=0.6). Virus-positive swabs were less often accompanied by respiratory symptoms in infants with CF (17% vs 23%; OR 0.64, 95% CI 0.43 to 0.95, p=0.026). This finding was pronounced for symptomatic human rhinovirus detection (7% vs 11%; OR 0.52, 95% CI 0.31 to 0.9, p=0.02)., Conclusions: Viral detection is not more frequent in infants with CF and respiratory symptoms during viral detection occur even less often than in healthy controls. It is likely an interplay of different factors such as local epithelial properties and immunological mechanisms that contribute to our findings., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Exhaled nitric oxide (FE NO ) is a well-known, non-invasive airway biomarker. In patients with Cystic Fibrosis (CF) FE NO is decreased. To understand if reduced FE NO is primary related to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) dysfunction or an epiphenomenon of chronic inflammation, we measured FE NO in 34 infants with CF prior to clinical symptoms and in 68 healthy controls. FE NO was lower in CF compared to controls (p=0.0006) and the effect was more pronounced in CF infants without residual CFTR function (p<0.0001). This suggests that FE NO is reduced in CF early in life, possibly associated with underlying CFTR dysfunction., (Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Background: In vitro systems of primary cystic fibrosis (CF) airway epithelial cells are an important tool to study molecular and functional features of the native respiratory epithelium. However, undifferentiated CF airway cell cultures grown under submerged conditions do not appropriately represent the physiological situation. A more advanced CF cell culture system based on airway epithelial cells grown at the air-liquid interface (ALI) recapitulates most of the in vivo-like properties but requires the use of invasive sampling methods. In this study, we describe a detailed characterization of fully differentiated primary CF airway epithelial cells obtained by non-invasive nasal brushing of pediatric patients., Methods: Differentiated cell cultures were evaluated with immunolabelling of markers for ciliated, mucus-secreting and basal cells, and tight junction and CFTR proteins. Epithelial morphology and ultrastructure was examined by histology and transmission electron microscopy. Ciliary beat frequency was investigated by a video-microscopy approach and trans-epithelial electrical resistance was assessed with an epithelial Volt-Ohm meter system. Finally, epithelial permeability was analysed by using a cell layer integrity test and baseline cytokine levels where measured by an enzyme-linked immunosorbent assay., Results: Pediatric CF nasal cultures grown at the ALI showed a differentiation into a pseudostratified epithelium with a mucociliary phenotype. Also, immunofluorescence analysis revealed the presence of ciliated, mucus-secreting and basal cells and tight junctions. CFTR protein expression was observed in CF (F508del/F508del) and healthy cultures and baseline interleukin (IL)-8 and IL-6 release were similar in control and CF ALI cultures. The ciliary beat frequency was 9.67 Hz and the differentiated pediatric CF epithelium was found to be functionally tight., Conclusion: In summary, primary pediatric CF nasal epithelial cell cultures grown at the ALI showed full differentiation into ciliated, mucus-producing and basal cells, which adequately reflect the in vivo properties of the human respiratory epithelium.

Lung function tests are commonly used to monitor lung disease in cystic fibrosis (CF). While practical, they cannot locate the exact origin of functional impairment. Contemporary magnetic resonance imaging (MRI) techniques provide information on the location of disease but the need for contrast agents constrains their repeated application. We examined the correlation between functional MRI, performed without administration of contrast agent, and lung clearance index (LCI) from nitrogen multiple-breath washout (N 2 -MBW).40 children with CF (median (range) age 12.0 (6-18) years) and 12 healthy age-matched controls underwent functional and structural MRI and lung function tests on the same day. Functional MRI provided semiquantitative measures of perfusion ( R Q ) and ventilation ( R FV ) impairment as percentages of affected lung volume. Morphological MRI was evaluated using CF-specific scores. LCI measured global ventilation inhomogeneity.MRI detected functional impairment in CF: R FV 19-38% and R Q 16-35%. R FV and R Q correlated strongly with LCI (r=0.76, p<0.0001 and r=0.85, p<0.0001, respectively), as did total morphology score (r=0.81, p<0.0001). All indices differed significantly between patients with CF and healthy controls (p<0.001).Noninvasive functional MRI is a promising method to detect and visualise perfusion and ventilation impairment in CF without the need for contrast agents., Competing Interests: Conflict of interest: Disclosures can be found alongside this article at erj.ersjournals.com, (Copyright ©ERS 2017.)

It is not known at what age lung function impairment may arise in children with cystic fibrosis (CF). We assessed lung function shortly after birth in infants with CF diagnosed by newborn screening.We performed infant lung function measurements in a prospective cohort of infants with CF and healthy controls. We assessed lung clearance index (LCI), functional residual capacity (FRC) and tidal breathing parameters. The primary outcome was prevalence and severity of abnormal lung function (±1.64 z-scores) in CF.We enrolled 53 infants with CF (mean age 7.8 weeks) and 57 controls (mean age 5.2 weeks). Compared to controls, LCI and FRC were elevated (mean difference 0.30, 95% CI 0.02-0.60; p=0.034 and 14.5 mL, 95% CI 7.7-21.3 mL; p<0.001, respectively), while ratio of time to peak tidal expiratory flow to expiratory time was decreased in infants with CF. In 22 (41.5%) infants with CF, either LCI or FRC exceeded 1.64 z-scores; three infants had both elevated LCI and FRC.Shortly after birth, abnormal lung function is prevalent in CF infants. Ventilation inhomogeneity or hyperinflation may serve as noninvasive markers to monitor CF lung disease and specific treatment effects, and could thus be used as outcome parameters for future intervention studies in this age group., Competing Interests: Conflict of interest: Disclosures can be found alongside this article at erj.ersjournals.com, (Copyright ©ERS 2017.)

Background: Multiple-breath washout (MBW) is increasingly used for infant lung function testing. Current guidelines recommend calculating lung clearance index (LCI) and functional residual capacity (FRC) at 2.5% of normalized tracer gas concentration, without clear recommendation for moment ratios (MR). Whether the 2.5% cut-off has the highest discriminative power to detect ventilation inhomogeneity in infants with lung diseases is unknown., Methods: We used sulfur-hexafluoride MBW measurements from 32 infants with cystic fibrosis, 32 preterm infants, and 32 healthy controls at postmenstrual age of 41-54 weeks. We compared the discriminative power to detect pathological values above the upper limit of normal for 12 different cut-offs between 20% and 1.5% for first and second MR (MR1, MR2), LCI, and FRC., Results: MR and LCI results changed significantly at different cut-offs. Mean MR2 in infants with cystic fibrosis increased from 2.4 to 7.2 units between 20% and 1.5% SF 6 . The ability of MR and LCI to discriminate between health and disease increased significantly with lower cut-offs. The 1.5% cut-off showed highest discriminative power: in infants with cystic fibrosis pathological MR2 values were found in 27 out of 89 (30%) and for LCI in 28/89 (32%). In preterm infants, pathological MR2 values were detected in 39 out of 73 (53%), and for LCI in 35/73 (48%). FRC remained stable throughout the washout., Conclusion: In infants, the diagnostic performance of MBW strongly depends on the point of analysis. The cut-off with the highest discriminative power to detect ventilation inhomogeneity in infants with cystic fibrosis and after preterm birth was at 1.5% tracer gas concentration. Pediatr Pulmonol. 2016;51:1373-1381. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Background: Respiratory tract infections and subsequent airway inflammation occur early in the life of infants with cystic fibrosis. However, detailed information about the microbial composition of the respiratory tract in infants with this disorder is scarce. We aimed to undertake longitudinal in-depth characterisation of the upper respiratory tract microbiota in infants with cystic fibrosis during the first year of life., Methods: We did this prospective cohort study at seven cystic fibrosis centres in Switzerland. Between Feb 1, 2011, and May 31, 2014, we enrolled 30 infants with a diagnosis of cystic fibrosis. Microbiota characterisation was done with 16S rRNA gene pyrosequencing and oligotyping of nasal swabs collected every 2 weeks from the infants with cystic fibrosis. We compared these data with data for an age-matched cohort of 47 healthy infants. We additionally investigated the effect of antibiotic treatment on the microbiota of infants with cystic fibrosis. Statistical methods included regression analyses with a multivariable multilevel linear model with random effects to correct for clustering on the individual level., Findings: We analysed 461 nasal swabs taken from the infants with cystic fibrosis; the cohort of healthy infants comprised 872 samples. The microbiota of infants with cystic fibrosis differed compositionally from that of healthy infants (p=0·001). This difference was also found in exclusively antibiotic-naive samples (p=0·001). The disordering was mainly, but not solely, due to an overall increase in the mean relative abundance of Staphylococcaceae in infants with cystic fibrosis compared with healthy infants (multivariable linear regression model stratified by age and adjusted for season; second month: coefficient 16·2 [95% CI 0·6-31·9]; p=0·04; third month: 17·9 [3·3-32·5]; p=0·02; fourth month: 21·1 [7·8-34·3]; p=0·002). Oligotyping analysis enabled differentiation between Staphylococcus aureus and coagulase-negative Staphylococci. Whereas the analysis showed a decrease in S aureus at and after antibiotic treatment, coagulase-negative Staphylococci increased., Interpretation: Our study describes compositional differences in the microbiota of infants with cystic fibrosis compared with healthy controls, and disordering of the microbiota on antibiotic administration. Besides S aureus, coagulase-negative Staphylococci also contributed to the disordering identified in these infants. These findings are clinically important in view of the crucial role that bacterial pathogens have in the disease progression of cystic fibrosis in early life. Our findings could be used to inform future studies of the effect of antibiotic treatment on the microbiota in infants with cystic fibrosis, and could assist in the prevention of early disease progression in infants with this disorder., Funding: Swiss National Science Foundation, Fondation Botnar, the Swiss Society for Cystic Fibrosis, and the Swiss Lung Association Bern., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Rhinoviruses (RVs) are associated with exacerbations of cystic fibrosis (CF), asthma and COPD. There is growing evidence suggesting the involvement of the interferon (IFN) pathway in RV-associated morbidity in asthma and COPD. The mechanisms of RV-triggered exacerbations in CF are poorly understood. In a pilot study, we assessed the antiviral response of CF and healthy bronchial epithelial cells (BECs) to RV infection, we measured the levels of IFNs, pattern recognition receptors (PRRs) and IFN-stimulated genes (ISGs) upon infection with major and minor group RVs and poly(IC) stimulation. Major group RV infection of CF BECs resulted in a trend towards a diminished IFN response at the level of IFNs, PRRs and ISGs in comparison to healthy BECs. Contrary to major group RV, the IFN pathway induction upon minor group RV infection was significantly increased at the level of IFNs and PRRs in CF BECs compared to healthy BECs., (Copyright © 2015 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Background and Objective: Rhinoviruses (RV) replicate in both upper and lower airway epithelial cells. We evaluated the possibility of using nasal epithelial cells (NEC) as surrogate of bronchial epithelial cells (BEC) for RV pathogenesis cell culture studies., Methods: We used primary paired NEC and BEC cultures established from healthy subjects and compared the replication of RV belonging to the major (RV16) and minor (RV1B) group, and the cellular antiviral and proinflammatory cytokine responses towards these viruses. We related antiviral and pro-inflammatory responses of NEC isolated from CF and COPD patients with those of BEC., Results: RV16 replication and major group surface receptor (ICAM-1) expression were higher in healthy NEC compared with BEC (P < 0.05); RV1B replication and minor group surface receptor (LDLR) expression were similar. Healthy NEC and BEC produced similar levels of IFN-β and IFN-λ2/3 upon RV infection or after simulation with poly(IC). IL-8 production was similar between healthy NEC and BEC. IL-6 release at baseline (P < 0.01) and upon infection with RV16 (P < 0.05) and poly(IC) stimulation (P < 0.05) was higher in NEC. RV1B viral load in NEC was related to RV1B viral load in BEC (r = 0.49, P = 0.01). There was a good correlation of IFN levels between NEC and BEC (r = 0.66, P = 0.0004 after RV1B infection). IL-8 production in NEC was related to IL-8 production in BEC (r = 0.48, P = 0.02 after RV1B infection)., Conclusion: NEC are a suitable alternative cellular system to BEC to study the pathophysiology of RV infections and particularly to investigate IFN responses induced by RV infection., (© 2015 Asian Pacific Society of Respirology.)

Vitamin D has immunomodulatory properties in the defence against pathogens. Its insufficiency is a widespread feature of cystic fibrosis (CF) patients, which are repeatedly suffering from rhinovirus (RV)-induced pulmonary exacerbations.To investigate whether vitamin D has antiviral activity, primary bronchial epithelial cells from CF children were pre-treated with vitamin D and infected with RV16. Antiviral and anti-inflammatory activity of vitamin D was assessed. RV and LL-37 levels were measured in bronchoalveolar lavage (BAL) of CF children infected with RV.Vitamin D reduced RV16 load in a dose-dependent manner in CF cells (10(-7 )M, p<0.01). The antiviral response mediated by interferons remained unchanged by vitamin D in CF cells. Vitamin D did not exert anti-inflammatory properties in RV-infected CF cells. Vitamin D increased the expression of the antimicrobial peptide LL-37 up to 17.4-fold (p<0.05). Addition of exogenous LL-37 decreased viral replication by 4.4-fold in CF cells (p<0.05). An inverse correlation between viral load and LL-37 levels in CF BAL (r=-0.48, p<0.05) was observed.RV replication in primary CF bronchial cells was reduced by vitamin D through the induction of LL-37. Clinical studies are needed to determine the importance of an adequate control of vitamin D for prevention of virus-induced pulmonary CF exacerbations., (Copyright ©ERS 2016.)

Background: Lung clearance index (LCI), a marker of ventilation inhomogeneity, is elevated early in children with cystic fibrosis (CF). However, in infants with CF, LCI values are found to be normal, although structural lung abnormalities are often detectable. We hypothesized that this discrepancy is due to inadequate algorithms of the available software package., Aim: Our aim was to challenge the validity of these software algorithms., Methods: We compared multiple breath washout (MBW) results of current software algorithms (automatic modus) to refined algorithms (manual modus) in 17 asymptomatic infants with CF, and 24 matched healthy term-born infants. The main difference between these two analysis methods lies in the calculation of the molar mass differences that the system uses to define the completion of the measurement., Results: In infants with CF the refined manual modus revealed clearly elevated LCI above 9 in 8 out of 35 measurements (23%), all showing LCI values below 8.3 using the automatic modus (paired t-test comparing the means, P < 0.001). Healthy infants showed normal LCI values using both analysis methods (n = 47, paired t-test, P = 0.79). The most relevant reason for false normal LCI values in infants with CF using the automatic modus was the incorrect recognition of the end-of-test too early during the washout., Conclusion: We recommend the use of the manual modus for the analysis of MBW outcomes in infants in order to obtain more accurate results. This will allow appropriate use of infant lung function results for clinical and scientific purposes., (© 2015 Wiley Periodicals, Inc.)

Virus-associated pulmonary exacerbations, often associated with rhinoviruses (RVs), contribute to cystic fibrosis (CF) morbidity. Currently, there are only a few therapeutic options to treat virus-induced CF pulmonary exacerbations. The macrolide antibiotic azithromycin has antiviral properties in human bronchial epithelial cells. We investigated the potential of azithromycin to induce antiviral mechanisms in CF bronchial epithelial cells. Primary bronchial epithelial cells from CF and control children were infected with RV after azithromycin pre-treatment. Viral RNA, interferon (IFN), IFN-stimulated gene and pattern recognition receptor expression were measured by real-time quantitative PCR. Live virus shedding was assessed by assaying the 50% tissue culture infective dose. Pro-inflammatory cytokine and IFN-β production were evaluated by ELISA. Cell death was investigated by flow cytometry. RV replication was increased in CF compared with control cells. Azithromycin reduced RV replication seven-fold in CF cells without inducing cell death. Furthermore, azithromycin increased RV-induced pattern recognition receptor, IFN and IFN-stimulated gene mRNA levels. While stimulating antiviral responses, azithromycin did not prevent virus-induced pro-inflammatory responses. Azithromycin pre-treatment reduces RV replication in CF bronchial epithelial cells, possibly through the amplification of the antiviral response mediated by the IFN pathway. Clinical studies are needed to elucidate the potential of azithromycin in the management and prevention of RV-induced CF pulmonary exacerbations., (Copyright ©ERS 2015.)

Background: Nitrogen multiple-breath washout (N2 MBW) using 100% oxygen (O2) has regained interest to assess efficiency of tracer gas clearance in, for example, children with Cystic Fibrosis (CF). However, the influence of hyperoxia on the infants' respiratory control is unclear. We assessed safety and impact on breathing pattern from hyperoxia, and if exposure to 40% O2 first induces tolerance to subsequent 100% O2 for N2 MBW., Methods: We prospectively enrolled 39 infants aged 3-57 weeks: 15 infants with CF (8 sedated for testing) and 24 healthy controls. Infants were consecutively allocated to the protocols comprising of 100% O2 or 40/100% O2 administered for 30 breaths. Lung function was measured using an ultrasonic flowmeter setup. Primary outcome was tidal volume (VT)., Results: None of the infants experienced apnea, desaturation, or bradycardia. Both protocols initially induced hypoventilation. VT temporarily declined in 33/39 infants across 10-25 breaths. Hypoventilation occurred independent of age, disease, and sedation. In the new 40/100% O2 protocol, VT returned to baseline during 40% O2 and remained stable during 100% O2 exposure. End-tidal carbon dioxide monitored online did not change., Conclusion: The classical N2 MBW protocol with 100% O2 may change breathing patterns of the infants. The new protocol with 40% O2 induces hyperoxia-tolerance and does not lead to changes in breathing patterns during later N2 washout using 100% O2. Both protocols are safe, the new protocol seems an attractive option for N2 MBW in infants., (© 2013 Wiley Periodicals, Inc.)

Background: We studied the ability of 4 single-breath gas washout (SBW) tests to measure immediate effects of airway clearance in children with CF., Methods: 25 children aged 4-16 years with CF performed pulmonary function tests to assess short-term variability at baseline and response to routine airway clearance. Tidal helium and sulfur hexafluoride (double-tracer gas: DTG) SBW, tidal capnography, tidal and vital capacity nitrogen (N2) SBW and spirometry were applied. We analyzed the gasses' phase III slope (SnIII--normalized for tidal volume) and FEV1 from spirometry., Results: SnIII from tidal DTG-SBW, SnIII from vital capacity N2-SBW, and FEV1 improved significantly after airway clearance. From these tests, individual change of SnIII from tidal DTG-SBW and FEV1 exceeded short-term variability in 10 and 6 children., Conclusions: With the tidal DTG-SBW, an easy and promising test for peripheral gas mixing efficiency, immediate pulmonary function response to airway clearance can be assessed in CF children., (Copyright © 2013 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Background: Although lung clearance index (LCI) is a sensitive indicator of mild cystic fibrosis (CF) lung disease, it is rarely measured due to lengthy protocols and the commercial unavailability of multiple-breath washout (MBW) setups and tracer gases. We used a newly validated, commercially available nitrogen (N2 ) MBW setup to assess success rate, duration, and variability of LCI within a 20 min timeframe, during clinical routine. We also evaluated the relationship between LCI and other clinical markers of CF lung disease., Methods: One hundred thirty six children (83 with CF) between 4 and 16 years were studied in a pediatric CF outpatient setting. One hundred eighteen out of 136 children were naïve to MBW. Within 20 min, each child was trained, N2 MBW was performed, and LCI was analyzed. We assessed intra- and between-test reproducibility in a subgroup of children., Results: At least one LCI was feasible in 123 (90%) children, with a mean (range) of 3.3 (1.2-6.4) min per test. Two or more measurements were feasible in 56 (41%) children. Comparing LCI in CF versus controls, LCI mean (SD) was 12.0 (3.9) versus 6.1 (0.9), and the intra- and inter-test coefficient of repeatability was 1.00 versus 0.81 and 0.96 versus 0.62, respectively. LCI was correlated with spirometry, blood gases, and Pseudomonas aeruginosa infection., Conclusions: Using available N2 MBW equipment, LCI measurements are practical and fast in children. LCI is correlated with markers of CF lung disease. Longer timeframes would be required for triplicate N2 MBW tests in inexperienced children., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Rhinovirus (RV)-induced pulmonary exacerbations are common in cystic fibrosis (CF) and have been associated with impaired virus clearance by the CF airway epithelium in vitro. Here, we assess in vivo the association of RV prevalence and load with antiviral defense mechanisms, airway inflammation, and lung function parameters in children with CF compared with a control group and children with other chronic respiratory diseases., Methods: RV presence and load were measured by real-time reverse transcription-polymerase chain reaction in BAL samples and were related to antiviral and inflammatory mediators measured in BAL and to clinical parameters., Results: BAL samples were obtained from children with CF (n = 195), non-CF bronchiectasis (n = 40), or asthma (n = 29) and from a control group (n = 35) at a median (interquartile range [IQR]) age of 8.2 (4.0-11.7) years. RV was detected in 73 samples (24.4%). RV prevalence was similar among groups. RV load (median [IQR] x 10(3) copies/mL) was higher in children with CF (143.0 [13.1-1530.0]), especially during pulmonary exacerbations, compared with children with asthma (3.0 [1.3-25.8], P = .006) and the control group (0.5 [0.3-0.5], P < .001), but similar to patients with non-CF bronchiectasis (122.1 [2.7-4423.5], P = not significant). In children with CF, RV load was negatively associated with interferon (IFN)- b and IFN- l , IL-1ra levels, and FEV 1 , and positively with levels of the cytokines CXCL8 and CXCL10., Conclusions: RV load in CF BAL is high, especially during exacerbated lung disease. Impaired production of antiviral mediators may lead to the high RV burden in the lower airways of children with CF. Whether high RV load is a cause or a consequence of inflammation needs further investigation in longitudinal studies.

In cystic fibrosis (CF), tests for ventilation inhomogeneity are sensitive but not established for clinical routine. We assessed feasibility of a new double-tracer gas single-breath washout (SBW) in school-aged children with CF and control subjects, and compared SBW between groups and with multiple-breath nitrogen washout (MBNW). Three SBW and MBNW were performed in 118 children (66 with CF) using a side-stream ultrasonic flowmeter setup. The double-tracer gas containing 5% sulfur hexafluoride and 26.3% helium was applied during one tidal breath. Outcomes were SBW phase III slope (SIII(DTG)), MBNW-derived lung clearance index (LCI), and indices of acinar (S(acin)) and conductive (S(cond)) ventilation inhomogeneity. SBW took significantly less time to perform than MBNW. SBW and MBNW were feasible in 109 (92.4%) and 98 (83.0%) children, respectively. SIII(DTG) differed between children with CF and controls, mean±sd was -456.7±492.8 and -88.4±129.1 mg·mol·L(-1), respectively. Abnormal SIII(DTG) was present in 36 (59%) children with CF. SIII(DTG) was associated with LCI (r= -0.58) and S(acin) (r= -0.58), but not with S(cond). In CF, steeply sloping SIII(DTG) potentially reflects ventilation inhomogeneity near the acinus entrance. This tidal SBW is a promising test to assess ventilation inhomogeneity in an easy and fast way.

Respiratory virus infections play an important role in cystic fibrosis (CF) exacerbations, but underlying pathophysiological mechanisms are poorly understood. We aimed to assess whether an exaggerated inflammatory response of the airway epithelium on virus infection could explain the increased susceptibility of CF patients towards respiratory viruses. We used primary bronchial and nasal epithelial cells obtained from 24 healthy control subjects and 18 CF patients. IL-6, IL-8/CXCL8, IP-10/CXCL10, MCP-1/CCL2, RANTES/CCL5 and GRO-α/CXCL1 levels in supernatants and mRNA expression in cell lysates were measured before and after infection with rhinoviruses (RV-16 and RV-1B) and RSV. Cytotoxicity was assessed by lactate dehydrogenate assay and flow cytometry. All viruses induced strong cytokine release in both control and CF cells. The inflammatory response on virus infection was heterogeneous and depended on cell type and virus used, but was not increased in CF compared with control cells. On the contrary, there was a marked trend towards lower cytokine production associated with increased cell death in CF cells. An exaggerated inflammatory response to virus infection in bronchial epithelial cells does not explain the increased respiratory morbidity after virus infection in CF patients.

Multiple breath washout (MBW) measurements have recently been shown to be sensitive for detection of early cystic fibrosis (CF) lung disease, with the lung clearance index (LCI) being the most common measure for ventilation inhomogeneity. The aim of this observational study was to describe the longitudinal course of LCI from time of clinical diagnosis during infancy to school-age in eleven children with CF. Elevated LCI during infancy was present in seven subjects, especially in those with later clinical diagnosis. Tracking of LCI at follow-up was evident only in the four most severe cases. We provide the first longitudinal data describing the long-term course of LCI in a small group of infants with CF. Our findings support the clinical usefulness of MBW measurements to detect and monitor early lung disease in children with CF already present shortly after clinical diagnosis., (Copyright © 2011 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

The chitinase-like protein YKL-40 was found to be increased in patients with severe asthma and chronic obstructive pulmonary disease (COPD), two disease conditions featuring neutrophilic infiltrates. Based on these studies and a previous report indicating that neutrophils secrete YKL-40, we hypothesized that YKL-40 plays a key role in cystic fibrosis (CF) lung disease, a prototypic neutrophilic disease. The aim of this study was (i) to analyze YKL-40 levels in human and murine CF lung disease and (ii) to investigate whether YKL-40 single-nucleotide polymorphisms (SNPs) modulate CF lung disease severity. YKL-40 protein levels were quantified in serum and sputum supernatants from CF patients and control individuals. Levels of the murine homologue BRP-39 were analyzed in airway fluids from CF-like βENaC-Tg mice. YKL-40SNPs were analyzed in CF patients. YKL-40 levels were increased in sputum supernatants and in serum from CF patients compared to healthy control individuals. Within CF patients, YKL-40 levels were higher in sputum than in serum. BRP-39 levels were increased in airways fluids from βENaC-Tg mice compared to wild-type littermates. In both CF patients and βENaC-Tg mice, YKL-40/BRP-39 airway levels correlated with the severity of pulmonary obstruction. Two YKL-40 SNPs (rs871799 and rs880633) were found to modulate age-adjusted lung function in CF patients. YKL-40/BRP-39 levelsare increased in human and murine CF airway fluids, correlate with pulmonary function and modulate CF lung disease severity genetically. These findings suggest YKL-40 as a potential biomarker in CF lung disease.

The diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis patients remains challenging, mainly owing to overlapping symptoms of the underlying lung disease with clinical symptoms of ABPA. In addition, a varying mixture of diagnostic criteria, including clinical status, radiological findings and immunological measurements, has led to confusion and differing recommendations. In order to help simplify as well as standardize the diagnostic criteria for ABPA, different serological markers have been evaluated in the last 20 years and their usefulness has been assessed in many clinical studies. This review presents current diagnostic criteria of ABPA, with a special focus on serum markers supporting the diagnosis and explains why the hunt for a serological marker for ABPA is still ongoing.

During a 3-month period, small-colony variant phenotypes of both Staphylococcus aureus and Pseudomonas aeruginosa were isolated from respiratory secretions of 8.2% and 9.2%, respectively, of 98 patients with cystic fibrosis, particularly those with advanced pulmonary disease and prolonged antibiotic exposure.

The diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) is a challenge. Thymus- and activation-regulated chemokine (TARC) has recently been reported to play a role in ABPA. The aim of this study was to compare the diagnostic value of TARC with that of known serological markers for diagnosis of ABPA in CF patients. The present study longitudinally followed 48 CF patients, of whom 12 had a diagnosis of ABPA according to Nelson's criteria, for 1-8 yrs with repeated measurements of serum total immunoglobulin (Ig)E, specific Aspergillus fumigatus IgE and IgG, specific IgE against recombinant A. fumigatus allergens (rAsp f) 1, 3, 4 and 6, and TARC. Median (interquartile range) TARC levels were 589 (465-673) pg x mL(-1) in ABPA patients and 232 (189-289) pg x mL(-1) in non-ABPA patients. Receiver operating characteristic curves revealed that TARC was superior to the other markers for diagnosis of ABPA. Diagnostic accuracy was greater for TARC (93%) than for total IgE (74%), or rAsp f 4 (75%) or f 6 (79%). The present study indicates that thymus- and activation-regulated chemokine may be useful in the diagnosis of allergic bronchopulmonary aspergillosis in cystic fibrosis patients. However, larger studies are needed before thymus- and activation-regulated chemokine can routinely be used in diagnostic algorithms.

Cystic fibrosis (CF) is the most common life-shortening autosomal recessive disorder in Caucasians, and is associated with at least one mutation on each CF transmembrane conductance regulator (CFTR) allele. Some patients, however, with only one identifiable point mutation carry on the other allele, a large deletion that is not detected by conventional screening methods. The overall frequency of large deletions in patients with CF is estimated to be 1-3%. Using the CFTR Multiplex Ligation dependent Probe Amplification Kit (MRC-Holland, Amsterdam, Netherlands) that allows the exact detection of copy numbers from all 27 exons in the CFTR gene, we screened 50 patients with only one identified mutation for large deletions in the CFTR gene. Each detected deletion was confirmed using our real-time polymerase chain reaction (PCR) assay and deletion-specific PCR reactions using junction fragment primers. We detected large deletions in eight patients (16%). These eight CF alleles belong to four different deletion types (CFTRindel2, CFTRdele14b-17b, CFTRdele17a-17b and CFTRdele 2-9) whereof the last is novel. Comparing detailed clinical data of all these patients with CF and the molecular genetic findings, we were able to elaborate criteria for deletion screenings and possible genotype-phenotype associations. In conclusion, we agree with other authors that deletion screenings should be implemented in routine genetic diagnostics of CF.

Aims: To determine whether the current practice of sweat testing in Swiss hospitals is consistent with the current international guidelines., Methods: A questionnaire was mailed to all children's hospitals (n = 8), regional paediatric sections of general hospitals (n = 28), and all adult pulmonology centres (n = 8) in Switzerland which care for patients with cystic fibrosis (CF). The results were compared with published "guidelines 2000" of the American National Committee for Clinical Laboratory Standards (NCCLS) and the UK guidelines of 2003., Results: The response rate was 89%. All 8 children's hospitals and 18 out of 23 answering paediatric sections performed sweat tests but none of the adult pulmonology centres. In total, 1560 sweat tests (range: 5-200 tests/centre/year, median 40) per year were done. 88% (23/26) were using Wescor systems, 73% (19/26) the Macroduct system for collecting sweat and 31% (8/26) the Nanoduct system. Sweat chloride was determined by only 62% (16/26) of all centres; of these, only 63% (10/16) indicated to use the recommended diagnostic chloride-CF-reference value of >60 mmol/l. Osmolality was measured in 35%, sodium in 42% and conductivity in 62% of the hospitals. Sweat was collected for maximal 30-120 (median 55) minutes; only three centres used the maximal 30 minutes sample time recommended by the international guidelines., Conclusions: Sweat testing practice in Swiss hospitals was inconsistent and seldom followed the current international guidelines for sweat collection, analyzing method and reference values. Only 62% were used the chloride concentration as a diagnostic reference, the only accepted diagnostic measurement by the NCCLS or UK guidelines.

We determined follow-up levels of specific serum IgE to the recombinant Aspergillus fumigatus (A. fumigatus) allergens rAsp f 1, 3, 4 and 6 in patients suffering from cystic fibrosis (CF) with and without allergic bronchopulmonary aspergillosis (ABPA). Over a 32-month period follow-up data of 74 patients were collected. According to serology, 11 CF patients were not sensitized (CF controls), 40 were sensitized to A. fumigatus (Asp. f-sens.) and 23 patients fulfilled the serologic criteria for ABPA. Of these 23 ABPA patients 11 expressed the full clinical ABPA picture (classicABPA) and 12 failed to show sufficient relevant clinical signs (seroABPA), despite positive serology. The 23 ABPA patients had 16-18 times higher serum levels of specific IgE to rAsp f 4 and/or rAsp f 6 than those of Asp. f-sens. patients (rAsp f 4: 31.3 +/- 45 EU/ml vs. 1.9 +/- 2.2 EU/ml and rAsp f 6: 39.0 +/- 44.3 EU/ml vs 2.1 +/- 1.7 EU/ml). The combination of increased total serum IgE (>1000 IU/l) and increased specific IgE to rAsp f 4 and/or rAsp f 6 allowed to diagnose classicABPA with 100% specificity and 64% sensitivity and with a high predicted positive (100%) and a high predicted negative (94%) value. During a combined treatment (seven patients) with oral corticosteroid and itraconazole, itraconazole alone (two patients) or neither oral corticosteroid nor itraconazole therapy (two patients) total serum IgE and specific IgE to rAsp f 4 and/or rAsp f 6 did decrease but did not normalize. Over the observation period, lung function remained unchanged, independent of whether oral steroids and/or concomitant itraconazole were either given or not given. In the follow-up of CF patients with ABPA under therapy the determination of total or specific IgE serum levels were of limited value to guide therapy., (Copyright 2005 Blackwell Munksgaard)

Up to 90% of patients with cystic fibrosis (CF) are chronically colonized with Pseudomonas aeruginosa, and 10% to 50% of CF patients are colonized with Aspergillus fumigatus. Despite an extensive inflammatory reaction, patients cannot eliminate the microorganisms. The present study demonstrates that an IL-10 mediated T-cell tolerance to major infectious agents A. fumigatus and P. aeruginosa plays an important role in the control of T-cell-mediated inflammatory responses in CF. Peripheral blood mononuclear cells of CF patients secreted significantly higher amounts of IL-10. T-cell response against recombinant A. fumigatus antigens rAsp f 3, rAsp f 4, rAsp f 6, and heat-inactivated P. aeruginosa was controlled by IL-10. Proliferation and interferon-gamma production was significantly increased when endogenous IL-10 was blocked in aspergillus and pseudomonas antigen-stimulated cells of CF patients. The role of IL-10 was further documented by increased spontaneous proliferation of peripheral blood mononuclear cells of CF patients after preincubation with antisense oligonucleotides blocking the synthesis of IL-10 receptor-associated kinases janus tyrosine kinase 1 and tyrosine kinase 2. Together, these data demonstrate an important role of IL-10-mediated peripheral T-cell tolerance to P. aeruginosa and A. fumigatus in the control of the intensity of the inflammatory T-cell response in CF.

Background: A false-positive sweat test in patients witl deficiency of glucose-6-phosphate-1 -dehydrogenase (EC 1.1.1.49; G6PD) is repeatedly reported. Methods: Sweat chloride or conductivity was measure in 11 patients with G6PD deficiency. Results: Mean (SD) chloride level (n = 8, median age 9.2 years, range 1.9-48.5) was 18.8 (9.6 mmol/l) and, mean (SD) sodium level was 26.0 (10.0 mmol/l(, respectively, and mean (SD) conductivity (n = 3, mediar age 6.6 years, range 1.9-40.5) was 34.3 (6.5 mmol/l). Conclusion: In sweat of 11 patients with G6PD deficiency we did not find any abnormality. The reason for alleged false positive sweat test in patients with G6PD deficiency is not known and we were unable to identify any original reference It appears that tables of putative false-positive sweat tests in several disease states have been directly "copied and pasted" from one paper or textbook to another without verifying the original literature, a phenomenon one can call "chain citation". [ABSTRACT FROM AUTHOR]