Tiddens, H.A.W.M.

A new Clinical Trials Directive to boost academic trials? (Article)

2013-03-22T00:00:00Z

Lung Function of Infants with Congenital Lung Lesions in the First Year of Life. (Article)

2012-10-23T00:00:00Z

Background: Several studies have evaluated short-term neonatal outcome in infants with congenital lung lesions (CLL) but clinical course and lung function in the longer term have not yet been documented. We hypothesized that clinical course and lung function would be negatively affected by surgical resection. Objective: To evaluate respiratory symptoms and lung function longitudinally in the first year of life in infants with CLL, and to analyse differences herein between infants managed by observation only and infants whose affected lung parts were resected. Methods: We evaluated respiratory symptoms and lung function at 6 and 12 months in 30 patients with CLL. Functional residual capacity (FRCp) and maximal expiratory flow at functional residual capacity (V′maxFRC) were measured with body plethysmography. SD scores were calculated for V′maxFRC. Results: Prevalence of respiratory symptoms did not differ between the groups. Mean FRCp(95% CI) was 25.3 (23.3-27.3) in the group managed by observation versus 27.3 (25.1-29.6) in the group managed by surgery (p = 0.149). Mean (95% CI) SDS V′maxFRC was -1.45 (-1.84 to -1.06) versus -1.41 (-1.90 to -0.91) (p = 0.892). Lung function did not change significantly over the 6-month period. Conclusion: Surgical resection did not seem to have negatively affected the clinical course and lung function. We recommend pulmonary follow-up of all CLL patients into adulthood to further identify any long-term effects of CLL and observation or surgery. Copyright

Improved treatment response to dornase alfa in cystic fibrosis patients using controlled inhalation (Article)

2011-12-01T00:00:00Z

Better treatment of obstructed small airways is needed in cystic fibrosis. This study investigated whether efficient deposition of dornase alfa in the small airways improves small airway obstruction. In a multicentre, double-blind, randomised controlled clinical trial, cystic fibrosis patients on maintenance treatment with 2.5 mL dornase alfa once daily were switched to a smart nebuliser and randomised to small airway deposition (n=24) or large airway deposition (n=25) for 4 weeks. The primary outcome parameter was forced expiratory flow at 75% of forced vital capacity (FEF75%). FEF75% increased significantly by 0.7 SD (5.2% predicted) in the large airways group and 1.2 SD (8.8%pred) in the small airways group. Intention-to-treat analysis did not showa significant difference in treatment effect between groups. Per-protocol analysis, excluding patients not completing the trial or with adherence <70%, showed a trend (p=0.06) in FEF75% Z-score and a significant difference (p=0.04) between groups in absolute FEF75% (L·s-1) favouring small airway deposition. Improved delivery of dornase alfa using a smart nebuliser that aids patients in correct inhalation technique resulted in significant improvement of FEF75% in children with stable cystic fibrosis. Adherent children showed a larger treatment response for small airway deposition. Copyright

Annual vaccination against influenza virus hampers development of virus-specific CD8 + T cell immunity in children (Article)

2011-11-01T00:00:00Z

Infection with seasonal influenza A viruses induces immunity to potentially pandemic influenza A viruses of other subtypes (heterosubtypic immunity). We recently demonstrated that vaccination against seasonal influenza prevented the induction of heterosubtypic immunity against influenza A/H5N1 virus induced by infection with seasonal influenza in animal models, which correlated with the absence of virus-specific CD8+T cell responses. Annual vaccination of all healthy children against influenza has been recommended, but the impact of vaccination on the development of the virus-specific CD8+T cell immunity in children is currently unknown. Here we compared the virus-specific CD8+T cell immunity in children vaccinated annually with that in unvaccinated children. In the present study, we compared influenza A virus-specific cellular and humoral responses of unvaccinated healthy control children with those of children with cystic fibrosis (CF) who were vaccinated annually. Similar virus-specific CD4+T cell and antibody responses were observed, while an age-dependent increase of the virus-specific CD8+T cell response that was absent in vaccinated CF children was observed in unvaccinated healthy control children. Our results indicate that annual influenza vaccination is effective against seasonal influenza but hampers the development of virus-specific CD8+T cell responses. The consequences of these findings are discussed in the light of the development of protective immunity to seasonal and future pandemic influenza viruses.

Effect of bronchoalveolar lavage-directed therapy on Pseudomonas aeruginosa infection and structural lung injury in children with cystic fibrosis: A randomized trial (Article)

2011-07-13T00:00:00Z

Context: Early pulmonary infection in children with cystic fibrosis leads to increased morbidity and mortality. Despite wide use of oropharyngeal cultures to identify pulmonary infection, concerns remain over their diagnostic accuracy. While bronchoalveolar lavage (BAL) is an alternative diagnostic tool, evidence for its clinical benefit is lacking. Objective: To determine if BAL-directed therapy for pulmonary exacerbations during the first 5 years of life provides better outcomes than current standard practice relying on clinical features and oropharyngeal cultures. Design, Setting, and Participants: The Australasian Cystic Fibrosis Bronchoalveolar Lavage (ACFBAL) randomized controlled trial, recruiting infants diagnosed with cystic fibrosis through newborn screening programs in 8 Australasian cystic fibrosis centers. Recruitment occurred between June 1, 1999, and April 30, 2005, with the study ending on December 31, 2009. Interventions: BAL-directed (n=84) or standard (n=86) therapy until age 5 years. The BAL-directed therapy group underwent BAL before age 6 months when well, when hospitalized for pulmonary exacerbations, if Pseudomonas aeruginosa was detected in oropharyngeal specimens, and after P aeruginosa eradication therapy. Treatment was prescribed according to BAL or oropharyngeal culture results. Main Outcome Measures: Primary outcomes at age 5 years were prevalence of P aeruginosa on BAL cultures and total cystic fibrosis computed tomography (CF-CT) score (as a percentage of the maximum score) on high-resolution chest CT scan. Results: Of 267 infants diagnosed with cystic fibrosis following newborn screening, 170 were enrolled and randomized, and 157 completed the study. At age 5 years, 8 of 79 children (10%) in the BAL-directed therapy group and 9 of 76 (12%) in the standard therapy group had P aeruginosa in final BAL cultures (risk difference, -1.7% [95% confidence interval, -11.6% to 8.1%]; P=.73). Mean total CF-CT scores for the BAL-directed therapy and standard therapy groups were 3.0% and 2.8%, respectively (mean difference, 0.19% [95% confidence interval, -0.94% to 1.33%]; P=.74). Conclusion: Among infants diagnosed with cystic fibrosis, BAL-directed therapy did not result in a lower prevalence of P aeruginosa infection or lower total CF-CT score when compared with standard therapy at age 5 years. Trial Registration: anzctr.org.au Identifier: ACTRN12605000665639.

Bronchiectasis and pulmonary exacerbations in children and young adults with cystic fibrosis (Article)

2011-07-01T00:00:00Z

Objective: Respiratory tract exacerbation rate (RTE-R) is a key clinical efficacy end point in cystic fibrosis (CF) trials. Chest CT scanning holds great potential as a surrogate end point. Evidence supporting the ability of CT scan scores to predict RTE-R is an important step in validating CT scanning as a surrogate end point. The objective of this study was to investigate the association between CT scan scores and RTE-R in a cohort of pediatric patients with CF. Methods: A retrospective review of data from pediatric patients with CF included chest CT scans, spirometry, and 2 years follow-up. RTE-R was defined as the number of IV antibiotics courses per year. CT scans were scored with the Brody-II system, assessing bronchiectasis, airway wall thickening, mucus, and opacities. Results: One hundred fifteen patients contributed 170 CT scans. Median age and FEV1at first CT scan were 12 years (range, 5-20 years) and 90% predicted (range, 23% predicted-132% predicted), respectively. Analyzing exacerbation counts using Poisson regression models, bronchiectasis score and FEV1both were found to be strong independent predictors of RTE-R in the subsequent 2 years. For the bronchiectasis score categorized in quartiles, RTE-R increased by factors of 1.8 (95% CI, 0.6-6.1; P =.31), 5.5 (95% CI, 1.9-15.4; P =.001), and 10.6 (95% CI, 3.8-29.4; P <.001), respectively, for each quartile compared with the quartile with the best (ie, lowest) scores. Similarly, time to first respiratory tract exacerbation was significantly associated with quartiles of both bronchiectasis score and FEV1. Conclusions: The CT scan bronchiectasis score is strongly associated with RTE-R in pediatric patients with CF, providing an important piece of evidence in the validation of CT scans as an end point for CF clinical trials.

Guideline on the design and conduct of cystic fibrosis clinical trials: The European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN) (Article)

2011-07-01T00:00:00Z

We describe the rationale for disease specific research networks in general as well as the aims and function of the European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN) specifically. The ECFS-CTN was founded in 2009 with the aim of improving the quality and quantity of clinical research in the area of cystic fibrosis (CF) in Europe. A network of 18 clinical trial sites in 8 European countries was established according to uniform state-of-the-art quality criteria. To support the ECFS-CTN in the acquisition, planning and conduct of clinical trials, the network is equipped with a coordinating centre, steering and executive committees, and committees for protocol review, standardization, training and networking as well as a data safety monitoring board. A strong partnership with European CF patient parent organizations aims to increase awareness of the need for efficient clinical research and the participation of patients in clinical trials.

Lung disease in FLNA mutation: Confirmatory report (Article)

2011-05-01T00:00:00Z

Recently in this journal, Masurel-Paulet et al. reported the association between pulmonary disease and a mutation in X-linked FLNA in a male patient. We confirm this association in a female patient, showing that this complication is not sex-specific. Our patient has a FLNA missense mutation (c.220G > A) and presented with cerebral periventricular nodular heterotopia, cardiovascular abnormalities, and pulmonary disease consisting of lobar emphysema of the right middle pulmonary lobe with severe malacia of the right sided bronchus intermedius. Surgical resection of the right middle lobe was necessary and she had long-term oxygen dependency. Symptoms improved with age.

Computed tomography and magnetic resonance imaging in cystic fibrosis lung disease (Article)

2010-12-01T00:00:00Z

Computed tomography (CT) is the current "gold standard" for assessment of lung morphology and is so far the most reliable imaging modality for monitoring cystic fibrosis (CF) lung disease. CT has a much higher radiation exposure than chest x-ray. The cumulative radiation dose for life-long repeated CT scans has limited its use for CF patients as their life expectancy increases. Clearly, no dose would be preferable over low dose when the same or more relevant information can be obtained. Magnetic resonance imaging (MRI) is comparable to CT with regard to the detection of most morphological changes in the CF lung. It is thought to be less sensitive to detect small airway disease. At the same time, MRI is superior to CT when it comes to the assessment of functional changes such as altered pulmonary perfusion. The recommendation is to further reduce radiation dose related to the use of CT and to use MRI in the follow-up of morphological changes where possible.

Structural lung changes, lung function, and non-invasive inflammatory markers in cystic fibrosis (Article)

2010-05-01T00:00:00Z

Cystic fibrosis (CF) lung disease is characterized by chronic airway inflammation and recurrent infections, resulting in (ir)reversible structural lung changes and a progressive decline in lung function. The objective of this study was to investigate the relationship between non-invasive inflammatory markers (IM) in exhaled breath condensate (EBC), lung function indices and structural lung changes, visualized by high resolution computed tomography (HRCT) scans in CF. In 34 CF patients, lung function indices (forced expiratory volume in 1 s, forced vital capacity [FVC], residual volume, and total lung capacity [TLC]) and non-invasive IM (exhaled nitric oxide, and condensate acidity, nitrate, nitrite, 8-isoprostane, hydrogen peroxide, interferon-gamma) were assessed. HRCT scans were scored in a standardized and validated way, a composite score and component scores were calculated. In general, the correlations between non-invasive IM and structural lung changes, and between IM and lung function were low (correlation coefficients <0.40). Patients with positive sputum Pseudomonas cultures had higher EBC nitrite levels and higher parenchymal HRCT subscores than patients with Pseudomonas-negative cultures (p < 0.05). Multiple linear regression models demonstrated that FVC was significantly predicted by hydrogen peroxide in EBC, and the scores of bronchiectasis and mosaic perfusion (Pearson correlation coefficient R = 0.78, p < 0.001). TLC was significantly predicted by 8-isoprostane, nitrate, hydrogen peroxide in EBC, and the mucous plugging subscore (R = 0.92, p < 0.01). Static and dynamic lung function indices in this CF group were predicted by the combination of non-invasive IM in EBC and structural lung changes on HRCT imaging. Future longitudinal studies should reveal whether non-invasive monitoring of airway inflammation in CF adds to better follow-up of patients.

Zien of raden? (Inaugural Lecture)

2010-02-12T00:00:00Z

Rede, uitgesproken bij de aanvaarding van het ambt van bijzonder hoogleraar kinderpulmonologie, in het bijzonder de ontwikkeling van de long, aan het Erasmus MC, Faculteit van de Erasmus Universiteit Rotterdam op 12 februari 2010

Cystic fibrosis lung disease starts in the small airways: Can we treat it more effectively? (Article)

2010-02-01T00:00:00Z

The aims of this article are to summarize existing knowledge regarding the pathophysiology of small airways disease in cystic fibrosis (CF), to speculate about additional mechanisms that might playa role, and to consider the available or potential options to treat it. In the first section, we review the evidence provided by pathologic, physiologic, and imaging studies suggesting that obstruction of small airways begins early in life and is progressive. In the second section we discuss how the relationships between CF transmembrane conductance regulator (CFTR), ion transport, the volume of the periciliary liquid layer and airway mucus might lead to defective mucociliary clearance in small airways. In addition, we discuss how chronic endobronchial bacterial infection and a chronic neutrophilic inflammatory response increase the viscosity of CF secretions and exacerbate the clearance problem. Next, we discuss how the mechanical properties of small airways could be altered early in the disease process and how remodeling can contribute to small airways disease. In the final section, we discuss how established therapies impact small airways disease and new directions that may lead to improvement in the treatment of small airways disease.We conclude that there are many reasons to believe that small airways play an important role in the pathophysiology of (early) CF lung disease. Therapy should be aimed to target the small airways more efficiently, especially with drugs that can correct the basic defect at an early stage of disease.

Modifier gene study of meconium ileus in cystic fibrosis: Statistical considerations and gene mapping results (Article)

2009-12-01T00:00:00Z

Cystic fibrosis (CF) is a monogenic disease due to mutations in the CFTR gene. Yet, variability in CF disease presentation is presumed to be affected by modifier genes, such as those recently demonstrated for the pulmonary aspect. Here, we conduct a modifier gene study for meconium ileus (MI), an intestinal obstruction that occurs in 16-20% of CF newborns, providing linkage and association results from large family and case-control samples. Linkage analysis of modifier traits is different than linkage analysis of primary traits on which a sample was ascertained. Here, we articulate a source of confounding unique to modifier gene studies and provide an example of how one might overcome the confounding in the context of linkage studies. Our linkage analysis provided evidence of a MI locus on chromosome 12p13.3, which was segregating in up to 80% of MI families with at least one affected offspring (HLOD = 2.9). Fine mapping of the 12p13.3 region in a large case-control sample of pancreatic insufficient Canadian CF patients with and without MI pointed to the involvement of ADIPOR2 in MI (p = 0.002). This marker was substantially out of Hardy-Weinberg equilibrium in the cases only, and provided evidence of a cohort effect. The association with rs9300298 in the ADIPOR2 gene at the 12p13.3 locus was replicated in an independent sample of CF families. A protective locus, using the phenotype of no-MI, mapped to 4q13.3 (HLOD = 3.19), with substantial heterogeneity. A candidate gene in the region, SLC4A4, provided preliminary evidence of association (p = 0.002), warranting further follow-up studies. Our linkage approach was used to direct our fine-mapping studies, which uncovered two potential modifier genes worthy of follow-up.

Severe acute asthma (Article)

2009-12-01T00:00:00Z

Severe acute asthma (SAA) is life threatening and warrants fast and effective intervention. The severity of SAA can be assessed through a focused and concise clinical examination. Important signs of a life threatening attack are decreased consciousness, imminent exhaustion, oxygen saturation below 85% and diminished air movement on auscultation (silent chest). The severity of SAA can be expressed in an asthma score. The relative contribution of airway inflammation, bronchoconstriction and mucusplugging must be weighed for treatment choices. The pillars of treatment of SAA in the general pediatric practice are oxygen, continuous nebulization of salbutamol, systemic corticosteroids, intravenous magnesium sulphate and perhaps intravenous salbutamol. Further steps in treatment of unresponsive SAA should be initiated in consultation with the pediatric intensive care. Reasons for transfer to a pediatric intensive care are imminent exhaustion and/or respiratory insufficiency, need for mechanical ventilation and intravenous salbutamol.

The spectrum of structural abnormalities on CT scans from patients with CF with severe advanced lung disease (Article)

2009-10-01T00:00:00Z

Rationale: In cystic fibrosis (CF), lung disease is the predominant cause of morbidity and mortality. Little is known about the spectrum of structural abnormalities on. CT scans from patients with CF with severe advanced lung disease (SALD). No specific CT scoring system for SALD is available. Objectives: To design a quantitative CT scoring system for SALD, to determine the spectrum of structural abnormalities in patients with SALD and to correlate the SALD system with an existing scoring system for mild CF lung disease and pulmonary function tests (PFTs). Methods: 57 patients with CF contributed one CT made during screening for lung transplantation. For the SALD system, lung tissue was divided into four components: infection/inflammation (including bronchiectasis, airway wall thickening, mucus and consolidations), air trapping/ hypoperfusion, bulla/cysts and normal/hyperperfused tissue. The volume proportion of the components was estimated on a 0-100% scale; mean volumes for the whole lung were computed. Scores were correlated with Brody-II scores and PFTs. Results: The SALD system identified a wide spectrum of structural abnormalities ranging from predominantly infection/inflammation to predominantly air trapping/ hypoperfusion. SALD infection/inflammation scores correlated with Brody-II scores (rs = 0.36-0.64) and SALD normal/hyperperfusion scores correlated with forced expiratory volume in 1 s (FEV1; rs = 0.37). Reproducibility for both systems was good. Conclusions: A CT scoring system was developed to characterise the structural abnormalities in patients with SALD. A wide spectrum was observed in SALD, ranging from predominantly air trapping to predominantly infection/ inflammation-related changes. This spectrum may have clinical implications for patients with SALD.

Cystic fibrosis: Are volumetric ultra-low-dose expiratory CT scans sufficient for monitoring related lung disease? (Article)

2009-10-01T00:00:00Z

Purpose: To assess whether chest computed tomography (CT) scores from ultra-low-dose end-expiratory scans alone could suffice for assessment of all cystic fibrosis (CF)-related structural lung abnormalities. Materials and Methods: In this institutional review board-approved study, 20 patients with CF aged 6-20 years (eight males, 12 females) underwent low-dose end-inspiratory CT and ultra-lowdose end-expiratory CT. Informed consent was obtained. Scans were randomized and scored by using the Brody-II CT scoring system to assess bronchiectasis, airway wall thickening, mucus plugging, and opacities. Scoring was performed by two observers who were blinded to patient identity and clinical information. Mean scores were used for all analyses. Statistical analysis included assessment of intra- and interobserver variability, calculation of intraclass correlation coefficients (ICCs), and Bland-Altman plots. Results: Median age was 12.6 years (range, 6.3-20.3 years), median forced expiratory volume in 1 second was 100% (range, 46%-127%) of the predicted value, and median forced vital capacity was 99% (range, 61%-123%) of the predicted value. Very good agreement was observed between end-inspiratory and end-expiratory CT scores for Brody-II total score (ICC = 0.96), bronchiectasis (ICC = 0.98), airway wall thickening (ICC = 0.94), mucus plugging (ICC = 0.96), and opacities (ICC = 0.90). Intra- and interobserver agreement were good to very good (ICC range, 0.70-0.98). Bland-Altman plots showed that differences in scores were independent of score magnitude. Conclusion: In this pilot study, CT scores from end-expiratory and end-inspiratory CT match closely, suggesting that ultralow-dose end-expiratory CT alone may be sufficient for monitoring CF-related lung disease. This would help reduce radiation dose for a single investigation by up to 75%.

Nocturnal cough in children with stable cystic fibrosis (Article)

2009-09-01T00:00:00Z

Introduction: To date no studies have been published on nocturnal cough frequency in children with stable CF. Aim of the study was to assess nocturnal cough frequency in children with CF. In addition nocturnal cough frequency was correlated with parameters of disease severity. Methods: During two nights cough was recorded with a digital audio recorder in 25 patients (mean age 13 years; range 6-19) with clinically stable CF. In addition oxygen saturation was measured. The day following the recording spirometrywas carried out.CTscoreswere obtained from the most recent routine CTscan. Cough was expressed in cough seconds (csec) and in cough seconds per hour (csec/hr).Results: Data shown are median values and interquartile range (IQR). First night: 8 csec (IQR 3-52); 0.9 csec/hr (IQR 0.3-6.1) Second night: 6 csec (IQR 2-32); 0.6 csec/hr (IQR 0.1-3.4). Csec in the 1st night did not correlate significantly with csec in the 2nd night. Only for the 2nd night a strong correlation was found between csec/hr and the FEV1%pred (rs=0.75, P<0.001) and FEF75%pred (rs=0.71, P=0.001). Bronchiectasis score correlated borderline with the mean csec/hr of both nights (rs=0.39, P=0.08). During both nights cough was significantly higher in the first hour of sleep (P≤0.04). Conclusion: Frequency of nocturnal coughing in children with CF was higher than that described for normal children. Nocturnal cough tended to be more severe in children with more advanced CF lung disease. Nocturnal cough was more severe in the first hour of sleep and varied from night-to-night.

Tracheomalacia in adults with cystic fibrosis: Determination of prevalence and severity with dynamic cine CT (Article)

2009-08-01T00:00:00Z

Purpose: To determine the prevalence and severity of tracheomalacia in adults with cystic fibrosis (CF) by using dynamic cine multidetector computed tomography (CT) and to correlate these findings with pulmonary function test (PFT) results and the severity of parenchymal lung disease. Materials and Methods: In this institutional review board-approved HIPAA-compliant study, 40 patients with CF (22 men, 18 women; mean age, 28 years ± 8 [standard deviation]; age range, 18-54 years) prospectively underwent PFTs, standard thin-section CT, and two dynamic cine multidetector CT acquisitions. Ten control subjects underwent dynamic cine multidetector CT. After standard thin-section CT was completed, dynamic cine multidetector CT was performed during a forced expiratory maneuver and during coughing. Dynamic cine multidetector CT images in nine patients were excluded. Maximal inspiratory, dynamic expiratory, and end-expiratory tracheal luminal areas were compared (Student t test) and correlated (Spearman rank) with PFT results and severity of parenchymal lung disease. Results: Mean predicted forced expiratory volume in 1 second (FEV1) was 70.6% ± 20.7, and mean Bhalla CT score was 41.8% ± 13.6. In patients with CF, dynamic cine mean tracheal cross-sectional area reduction was 51.7% ± 18.4 (range, 9%-89%) for forced expiratory maneuvers and 68.8% ± 11.7 (range, 18%-88%) for coughing (P = .001). Tracheomalacia was demonstrated in 24 (69%) patients and no control subjects during forced expiratory maneuvers (P = .001) and in 10 (29%) patients and one (10%) control subject during coughing. For end-expiration images, mean tracheal luminal reduction was 16.1% ± 14.0% (range, 0.0%-53.0%), with one patient demonstrating tracheal luminal reduction of more than 50%. There was no correlation between tracheal cross-sectional luminal reduction and either predicted FEV1or CT Bhalla score. Conclusion: Tracheomalacia depicted at dynamic cine multidetector CT is a highly prevalent finding in adults with CF.

Lung imaging in cystic fibrosis (Article)

2009-03-01T00:00:00Z

Management of CF patients currently relies on clinical status, lung function tests, sputum cultures and scoring systems based on chest X-ray (CXR). None of these tests give adequate information about regional lung function or are sensitive enough to demonstrate subtle changes that may aid in assessing early lung disease status, planning therapy or evaluating response to treatment. There is increasing evidence from recent studies with CT and MRI that current routine measures of lung physiology, (spirometry) and structure (CXR), may not accurately reflect disease progression nor identify early stages of lung disease, often remaining within a normal range even when significant and irreversible pulmonary damage has already occurred. Thus accurate, non-invasive, regional methods of diagnosis and follow up of CF patients based upon imaging endpoints are highly desirable. In this paper, state of the art methods of imaging signs of lung disease in the CF lung are reviewed with discussions on the technical advances in CT, proton and hyperpolarised gas MRI with example images from groups active in the area of CF lung imaging.

Lung morphology assessment using MRI: A robust ultra-short TR/TE 2D steady state free precession sequence used in cystic fibrosis patients (Article)

2009-02-01T00:00:00Z

To evaluate feasibility and diagnostic quality of ultra-short TR/TE two-dimensional (2D) steady state free precession (SSFP) MRI for cystic fibrosis (CF) patients. We performed lung MRI at 1.5 Tesla in 20 CF-patients (6-17 years, 12 males). Axial, coronal, and sagittal sections were acquired in inspiration and expiration with maximum breath-hold time 10 s. MR and CT images were scored using a modified Brody scoring system to assess bronchiectasis, mucous plugging, atelectasis/consoli-dations, and air trapping. All images were scored by two experienced observers. A complete MR investigation took maximally 15 min. Maximal breath-holds were only 10 s and well tolerated. MRI identified major bronchiectasis, mucous plugging and at-electasis. End-expiratory scans showed patches of parenchyma with reduced signal intensity that may corresponded to areas of trapped air on expiratory CT scans. This MRI protocol based on ultra-short TR/TE 2D SSFP is quick and well tolerated and provides highly relevant imaging features as seen on CT in CF patients. Most importantly, the SNR of the expiratory scans enables to visualize air trapping. The preliminary results of this study suggest MRI as a noteworthy additional imaging tool for routine monitoring of CF patients.

Airway dimensions in bronchopulmonary dysplasia: Implications for airflow obstruction (Article)

2008-12-01T00:00:00Z

The cause of lung function abnormalities in bronchopulmonary dysplasia (BPD) is incompletely understood, even in the "new era" of this disease. Altered airwaywall dimensions are important in the pathogenesis of airflow obstruction in diseases such as asthma and chronic obstructive pulmonary disease. Whether airway wall dimensions contribute to lung function abnormalities in BPD is unknown. The purpose of this study was to investigate airway wall dimensions in relation to airway size in BPD. Lung tissue of patients with BPD was obtained at autopsy, and lung tissue from children who died from sudden infant death syndrome (SIDS) served as control. Airway wall dimensions and epithelial loss were measured in 75 airways from 5 BPD patients and 176 airways from 11 SIDS patients. Repeated measures analysis of variance was used to assess the relationships between airway wall dimensions and airway size for BPD and SIDS patients. Little epithelial loss was present in the BPD patients while extensive loss was observed in some of the SIDS patients. The inner wall area, outer wall area, epithelium area and smooth muscle area were all substantially larger (all P < 0.001) in BPD than in SIDS patients. It is likely that the increased thickness of the airway wall components contributes to airflow obstruction in BPD patients.

Yield from Flexible Bronchoscopy in Pediatric Cystic Fibrosis Patients (Article)

2008-10-01T00:00:00Z

BACKGROUND : Recent data on the yield of bronchoscopy in pediatric cystic fibrosis (CF) patients are lacking. Therapeutic bronchoscopic lavage with the mucolytic recombinant human deoxyribonuclease (rhDNase) has been used during CF bronchoscopies, but efficacy data are scarce. METHODS: A retrospective review of all bronchoscopies performed in pediatric CF patients in our hospital in the past 15 years. AIMS OF THE STUDY: To evaluate indications for and safety of bronchoscopy in pediatric CF patients, to describe the findings of bronchoscopy and the contribution of these findings to clinical management, and to evaluate the application of bronchoscopic lavage with rhDNase. RESULTS: Between 1992 and 2007, 66 bronchoscopies were performed in 48 CF patients (25 males) at a median (range) age of 8.3 (0.1 to 20.4) years. Indications for bronchoscopy were persistent atelectasis (42%), refractory symptoms (29%), need for microbiologic culture (11%), suspected anatomic abnormality (11%), and bronchial toilet (7%). Relevant new information with therapeutic consequences was obtained in 28 (42%) bronchoscopies, including a first Pseudomonas aeruginosa infection (n≤3), infection with atypical mycobacteria (n≤3), or Aspergillus fumigatus (n≤5), and severe tracheo(broncho)malacia (n≤4). In patients with atelectasis, rhDNase lavage was associated with improved chest radiograph scores and a transient decline in forced vital capacity. In 7 of 11 patients with refractory symptoms, lung function tended to improve after rhDNase lavage. No serious complications were observed after bronchoscopy and rhDNase lavage. CONCLUSIONS: Bronchoscopy provides clinically relevant information in about 40% of these pediatric CF patients. Lavage with rhDNase seemed safe, and was associated with improved chest radiographs in patients with therapy resistant atelectasis. Copyright

Structural and functional lung disease in primary ciliary dyskinesia (Article)

2008-08-01T00:00:00Z

Background: High-resolution CT (HRCT) scan data on primary ciliary dyskinesia (PCD) related lung disease are scarce. Study objectives: We evaluated the lung disease in children and adults with PCD by a modified Brody composite HRCT scan score to assess the prevalence of the structural abnormalities; to evaluate the correlation among HRCT scan scores, spirometry findings, and clinical data; and to compare the PCD scores with those of age-matched and sex-matched cystic fibrosis (CF) patients. Patients and methods: Twenty PCD patients (age range, 4.6 to 27.5 years) underwent HRCT scanning, spirometry, and deep throat or sputum culture. A modified Brody score was used to assess bronchiectasis, mucous plugging, peribronchial thickening, parenchyma abnormalities, and mosaic perfusion. Results: The total HRCT scan score was 6% of the maximal score (range, 0.5 to 25.5). Subscores were as follows: bronchiectasis, 5.6%; mucous plugging, 5.6%; peribronchial thickening, 8.3%; parenchyma, 3%; and mosaic perfusion, 0%. The prevalence of lung changes were as follows: bronchiectasis, 80%; peribronchial thickening, 80%; mucous plugging, 75%; parenchyma, 65%; and mosaic perfusion, 45%. Sixteen of 19 PCD patients had positive culture findings, and the most common pathogen found was Haemophilus influenzae (84%). The total HRCT scan score was significantly related to age (p = 0.006), FEV1(p = 0.02), and FVC (p = 0.02). The bronchiectasis subscore was significantly related to FEV1(p = 0.04) and FVC (p = 0.03). In CF patients, the total HRCT scan score was significantly higher than that in PCD patients (p = 0.02). Conclusions: PCD patients show significantly lower pulmonary HRCT scan scores than CF patients. The PCD total and bronchiectasis scores correlate with spirometry findings. The PCD HRCT scan score might be used for longitudinal assessment and/or represent an outcome surrogate in future studies. Copyright

Estimation of the radiation dose from CT in cystic fibrosis (Article)

2008-05-01T00:00:00Z

Authors' reply [4] (Article)

2007-12-01T00:00:00Z

Pharmacokinetics of inhaled monodisperse beclomethasone as a function of particle size (Article)

2007-09-01T00:00:00Z

Aims: For optimal efficacy, antiasthma drugs should be delivered to the desired region in the airways. To date, the optimal particle size for steroids in adults is not known. The aim of the study was to evaluate the pulmonary bioavailability for inhaled beclomethasone dipropionate (BDP) aerosols of different particle sizes. Methods: In a randomized single-blind crossover trial, 10 mild asthmatic patients inhaled monodisperse BDP aerosols with mass median aerodynamic diameters (MMADs) of 1.5, 2.5 and 4.5 μm. Gastrointestinal absorption was blocked by activated charcoal. Plasma concentrations of 17-beclomethasone monopropionate (17-BMP) were measured by liquid chromatography plus mass spectrometry. Results: Aerosols with MMADs of 1.5 μm, 2.5 μm, and 4.5 μm gave mean maximum concentrations (Cmax) of 17-BMP of 475 pg ml-1, 1300 pg ml-1, and 1161 pg ml-1, respectively. The area under the curve (AUC) values of 17-BMP for MMADs of 1.5 μm, 2.5 μm, and 4.5 μm were 825 pg ml-1h, 2629 pg ml-1h, and 2276 pg ml-1h, respectively. The mean terminal half-time of 17-BMP for all three aerosol sizes was around 1.5 h. Conclusions: Monodisperse BDP aerosols with a MMAD of 1.5 μm gave two-three fold lower values for Cmaxand AUC than those with MMADs of 2.5 and 4.5 μm.

Monitoring cystic fibrosis lung disease in clinical trials: Is it time for a change? (Article)

2007-08-01T00:00:00Z

Imaging and clinical trials in cystic fibrosis (Article)

2007-08-01T00:00:00Z

Lung function parameters have been used in most therapeutic studies to date. Thanks to improvements in cystic fibrosis (CF) therapy, these parameters have become a less sensitive endpoint in clinical studies. Computed tomography (CT) in CF can identify highly relevant structural lung changes, such as bronchiectasis and air trapping. CT scoring systems have been developed to quantify in a systematic fashion these structural changes on CT scans. Clinical studies have been conducted using CT scores as an outcome parameter. These studies suggest strongly that CT scoring ismore sensitive than pulmonary function tests for the detection of relevant disease progression in CF. Bronchiectasis, which is progressive and irreversible in CF, is probably the most relevant structural change on CT scans that can be scored reliably. CT measurement of airway wall thickening is possible. Airway wall thickening is related to inflammation; thus, this endpoint is of significance for interventional studies that include antiinflammatory drugs.

Cystic fibrosis-specific computed tomography scoring (Article)

2007-08-01T00:00:00Z

This article presents a review and discussion of the current knowledge regarding cystic fibrosis (CF)-specific scoring of chest computed tomography (CT) scans. First, the basic principles of CT scoring systems in CF are described. Second, between- and within-observer variability of a composite CT score and of component CT scores are reviewed, and issues regarding training of CT scan readers discussed. Third, arguments regarding whether CT scoring systems are ready to be used in clinical studies as a surrogate endpoint are summarized. The between- and within-observer variability of the present CT composite scoring systems is low enough to be useful for clinical studies, although the variability for some of the component scores is larger than for others. Scoring systems fulfill the requirements for surrogate endpoints for CF lung disease, but this role could be further strengthened by including CT scans in large trials and demonstrating the correlation with true endpoints. The conclusion presented is that, given the experience of the variety of published scoring systems, it is important to develop a consensus CT scoring system for future studies in CF. Such a scoring system should evaluate all lung lobes individually and include all relevant CT findings in CF. Development of reference images for the components of this system will be important in reducing the variability between observers and to train new readers.

RhDNase before airway clearance therapy improves airway patency in children with CF (Article)

2007-07-01T00:00:00Z

Introduction: Little is known about the optimal timing of rhDNase nebulization in relation to airway clearance therapy (ACT). Objective: To compare the effects of rhDNase before ACT versus rhDNase after ACT in children with CF. Methods: Design: randomized, double blind, double dummy, cross over study. Inclusion criteria: CF, stable clinical condition, rhDNase maintenance therapy. Children in Group I inhaled rhDNase 30 minutes before ACT, and placebo directly after ACT in week 1-3. The protocol was reversed during week 4-6. Group II performed the reversed sequence. Patients continued their daily routine ACT. Primary endpoint: MEF25%pred. Pulmonary functions tests were performed on days 0, 14, 21, 35 and 42. In weeks 3 and 6 children scored cough and sputum production on daily diary cards. Results: 24 patients completed the study. Mean age = 12 years (range 7-19). Mean MEF25%pred was 5.8% higher after 3 weeks of rhDNase before ACT, compared to rhDNase after ACT (58.3% vs 52.5%, p = 0.01). There were no significant differences for any of the other variables. Conclusion: Inhalation of rhDNase before ACT improves peripheral airway patency in children with cystic fibrosis. Since all children were already on maintenance rhDNase therapy before the study, this effect is additional to any existing effect of regular rhDNase.

Facemasks and aerosol delivery by metered dose inhaler-valved holding chamber in young children: A tight seal makes the difference (Article)

2007-05-08T00:00:00Z

A facemask on a valved holding chamber (VHC) facilitates the inhalation of aerosols from metered dose inhalers (MDI) for young children. Only recently the facemask has been recognized as a vital part for efficient aerosol delivery. Several in vitro and in vivo studies show that a tight seal of the facemask is crucial for optimal aerosol deposition to the lungs. Even a small leak can reduce the dose delivered to the lungs considerably. However, a tight seal is difficult to obtain when a child is not cooperative. Depending on the design of the facemask, it is easier to obtain a good seal. Factors such as dead space, shape, and material should be considered when designing a facemask. However, when a child is upset and not cooperative during the administration, aerosol deposition will be minimal, even with the best-designed facemask.

Aerosol therapy by pressured metered-dose inhaler-spacer in sleeping young children: To do or not to do? (Article)

2006-08-01T00:00:00Z

One third of young children are distressed during inhalation therapy. It has been suggested that administration during sleep could be a good alternative for these children. A laboratory study in our department using an infant upper airway model showed significantly higher lung doses from a pressured metered-dose inhaler (pMDI)-spacer for sleep-breathing patterns compared with wake-breathing patterns. Objective: We set up a daily life study to investigate the feasibility of aerosol administration by means of pMDI-spacer in sleeping young children. Design: Over a period of 3 weeks, 30 children (age range, 6 to 23 months) with recurrent wheeze daily inhaled 1 puff of budesonide aerosol (200 μg) while awake and 1 puff during sleep. Filters positioned between the chamber and the facemask trapped the budesonide aerosol. Parents scored the child's asthma symptoms, degree of cooperation, and feasibility of administration on diary cards. Results: In 69% of the sleep administrations, the children woke up, and in 75% of these cases the children were distressed. The mean filter dose (expressed as the percentage of the nominal dose) while awake was 47%, and during sleep it was 16% (p = 0.007). The median within-subject dose variability while awake was 50%, and during sleep it was 110% (p = 0.007). Conclusion: Aerosol administration by means of pMDI-spacer during sleep offers no advantage and is not a feasible treatment option in most young children.

Macrolide resistance of Staphylococcus aureus and Haemophilus species associated with long-term azithromycin use in cystic fibrosis (Article)

2006-04-01T00:00:00Z

OBJECTIVES: Azithromycin is used to modulate exuberant inflammatory response in patients with cystic fibrosis (CF). The purpose of this study was to determine the association between long-term use of azithromycin in CF patients and change over time in macrolide susceptibility of Staphylococcus aureus and Haemophilus spp. METHODS: The study was performed at the Erasmus MC-Sophia Children's Hospital. CF patients' sputum cultures were obtained at routine visits and at pulmonary exacerbations. All cultures between January 1999 and March 2004 were included. Antibiotic susceptibility of S. aureus and Haemophilus spp. was tested routinely. Susceptibility was compared with isolates from sputum of non-CF patients. Logistic regression was used to analyse the association between azithromycin use and resistance, adjusting for age, Pseudomonas carriage and time-trends. RESULTS: In March 2004 one-third of CF patients were on azithromycin maintenance treatment. S. aureus (715 isolates) and/or Haemophilus (537 isolates) were cultured in 141 of the 155 patients on one or more occasions. The study period was divided into octiles. Erythromycin resistance in S. aureus increased from 6.9 to 53.8% and clarithromycin resistance in Haemophilus spp. from 3.7 to 37.5%. Resistance but also isolation rates were strongly related to azithromycin use. Resistance of 3217 S. aureus control isolates remained stable and resistance of 3257 Haemophilus controls increased, although at a slower rate than CF isolates. CONCLUSIONS: Over a 4 year period, azithromycin maintenance therapy in our CF population was associated with an increase in macrolide resistance in S. aureus and Haemophilus spp

Changes in airway dimensions on computed tomography scans of children with cystic fibrosis. (Article)

2005-07-15T00:00:00Z

RATIONALE: In cystic fibrosis (CF), chronic bacterial infection and inflammation lead to progressive airway wall thickening and lumen dilatation. Objectives: To quantify airway wall thickening and lumen dilatation in children with CF over a 2-year interval. METHODS: Children with CF (n = 23) who had two computed tomography (CT) scans (CT(cf1) and CT(cf2)) combined with pulmonary function tests (PFTs), with a 2-year interval between measurements, were compared with control subjects (n = 21) who had one CT (CT(controls)). On cross-sectional cut airway-artery pairs, airway wall area (WA), airway lumen area (LA) and perimeter, and arterial area (AA) were quantified. LA/AA (= marker of bronchiectasis), airway wall thickness (AWT), and WA/AA (= markers of wall thickness) were calculated. CT scans were scored using four different scoring systems. PFTs were expressed as percent predicted. RESULTS: Airway WA-to-AA ratio was 1.45 (p < 0.001) and airway LA-to-AA ratio was 1.92 times higher (p < 0.001) in children with CF compared with age-matched control subjects. LA/AA and WA/AA remained unchanged from CT(cf1) to CT(cf2) and did not increase with age. AWT as a function of airway size increased from CT(cf1) to CT(cf2) by 2% (0.03 mm; p = 0.02). The change in AWT was inversely related to the change in forced expiratory flow between 25 and 75% of expiratory VC (p = 0.002). CONCLUSIONS: In CF, quantitative measurements of airways on CT scans show an increased ratio between airway LA and AA and progressive airway wall thickening. Scoring systems show progression of bronchiectasis but unchanged AWT. PFTs remained stable.

Pulmonary disease assessment in cystic fibrosis: comparison of CT scoring systems and value of bronchial and arterial dimension measurements. (Article)

2004-05-01T00:00:00Z

PURPOSE: To retrospectively compare thin-section computed tomographic (CT) scores obtained with five scoring systems for assessment of pulmonary disease in children with cystic fibrosis and to determine additional value of bronchial and arterial dimension measurements. MATERIALS AND METHODS: Scores obtained with five thin-section CT scoring systems were compared. A score of 0 indicated the absence of abnormalities; a higher score meant that more structural abnormalities were seen. Three observers assigned scores and then reassigned scores after intervals varying from 1-2 weeks to 1-2 months at review of thin-section CT scans obtained in 25 children with cystic fibrosis. Interobserver and intraobserver reliability was calculated with intraclass correlation coefficients. Quantitative measurements of bronchial and arterial dimensions were obtained. Thin-section CT scores were correlated (Spearman correlation) with bronchial and arterial dimensions and with results of pulmonary function tests (PFTs), such as forced expiratory volume in 1 second (FEV(1)). RESULTS: Scores with all five scoring systems were reproducible, with intraclass correlation coefficients of 0.74 and higher (P <.05), and showed significant correlations with FEV(1) (R = -0.73 to -0.69, P <.01). Ratio of bronchial diameter to accompanying pulmonary arterial diameter was correlated with thin-section CT scores but not with FEV(1). Ratio of bronchial wall thickness to accompanying pulmonary arterial diameter was not correlated with thin-section CT scores or PFT results. CONCLUSION: Thin-section CT scores were reproducible and were correlated with PFT results. Measurements of bronchial dimensions were not significantly related to scores or PFT results.

Progressive damage on high resolution computed tomography despite stable lung function in cystic fibrosis (Article)

2004-01-01T00:00:00Z

For effective clinical management of cystic fibrosis (CF) lung disease it is important to closely monitor the start and progression of lung damage. The aim of this study was to investigate the ability of high-resolution computed tomography (HRCT) scoring systems and pulmonary function tests (PFT) to detect changes in lung disease. CF children (n=48) had two HRCT scans in combination with two PFT 2 yrs apart. Their scans were scored using five scoring systems (Castile, Brody, Helbich, Santamaria and Bhalla). "Sensitivity" was defined as the ability to detect disease progression. In this group of children, HRCT scores worsened. PFT remained unchanged or improved. Of the HRCT parameters, mucous plugging and the severity, extent and peripheral extension of bronchiectasis worsened significantly. Relationships between changes in HRCT scores and PFT were weak. Substantial structural lung damage was evident in some children who had normal lung function. These data show that high-resolution computed tomography is more sensitive than pulmonary function tests in the detection of early and progressive lung disease, and suggest that high-resolution computed tomography may be useful in the follow up of cystic fibrosis children and as an outcome measure in studies that aim to reduce lung damage.

Extra-fine particles improve lung delivery of inhaled steroids in infants: a study in an upper airway model (Article)

2003-01-01T00:00:00Z

BACKGROUND: The particles of a new hydrofluoroalkane-134a (HFA)-beclomethasone dipropionate (BDP) metered-dose inhaler (Qvar; 3M Pharmaceuticals; St. Paul, MN) are considerably smaller than those of chlorofluorocarbon (CFC)-BDP. This may improve lung deposition in infants who inhale nasally and have irregular breathing patterns and small airways. Aim: To compare the dose delivered to the lungs of HFA-BDP and CFC-BDP at different breathing patterns using an upper airway model of an infant. METHODS: An anatomically correct upper airway model of a 9-month-old child with an open nasal airway was connected to an impactor and breathing simulator. HFA-BDP, 100 microg, and CFC-BDP, 100 micro g, were delivered to the model through a detergent-coated, small-volume spacer. The total dose leaving the model (lung dose), its particle size distribution, and median mass aerodynamic diameter (MMAD) were assessed during simulated tidal breathing with tidal volumes (VTs) of 50 mL, 100 mL, and 200 mL, and 30 breaths/min. Dose was expressed as percentage of nominal dose. RESULTS: Lung doses for HFA-BDP were 25.4%, 26.5%, and 30.7% compared with 6.8%, 4.8%, and 2.1% for CFC-BDP at VTs of 50 mL, 100 mL, and 200 mL, respectively. The dose of particles < 2.1 microm to the lung for HFA-BDP was 23 to 28% compared with 0.6 to 0.8% for CFC-BDP. The lung dose of CFC-BDP mainly consisted of particles between 2.1 microm and 4.7 microm. MMAD for HFA-BDP was 1.2 microm, and 2.6 to 3.3 microm for CFC-BDP depending on VT. The lung dose for CFC-BDP decreased significantly with increasing VT. HFA-BDP lung dose did not alter significantly with VT. CONCLUSIONS: In this infant model study, the use of HFA-BDP with a high dose of particles < 2.1 microm improves the dose delivered to the lungs substantially. Furthermore, the large proportion of extra-fine particles in HFA-BDP results in lung doses less dependent on breathing pattern compared with CFC-BDP.

Estimation of lung growth using computed tomography (Article)

2003-01-01T00:00:00Z

Anatomical studies suggest that normal lungs grow by rapid alveolar addition until about 2 yrs of age followed by a gradual increase in alveolar dimensions. The aim of this study was to examine the hypothesis that normal lung growth can be monitored by computed tomography (CT). Therefore, the gas volume per gram of lung tissue was estimated from measurements of lung density obtained from CT scans performed on children throughout the growth period. CT scans were performed on 17 males and 18 females, ranging in age from 15 days-17.6 yrs. CT-measured lung weight was correlated with predicted post mortem values and CT measured gas volume with predicted values of functional residual capacity. The median value for lung expansion was 1.86 mL x g(-1) at 15 days, decreased to 0.79 mL x g(-1) by 2 yrs and then increased steadily to 5.07 mL x g(-1) at 17 yrs. Computed tomography scans can be used to estimate lung weight, gas volume and expansion of normal lungs during the growth period. The increase in the lung expansion after the age of 2 yrs suggests progressive alveolar expansion with increasing lung volume.

Bronchodilation in infants with malacia or recurrent wheeze (Article)

2003-01-01T00:00:00Z

BACKGROUND: Controversy remains regarding the effectiveness of bronchodilators in wheezy infants. AIMS: To assess the effect of inhaled beta(2) agonists on lung function in infants with malacia or recurrent wheeze, and to determine whether a negative effect of beta(2) agonists on forced expiratory flow (V'(maxFRC)) is more pronounced in infants with airway malacia, compared to infants with wheeze. METHODS: We retrospectively analysed lung function data of 27 infants: eight with malacia, 19 with recurrent wheeze. Mean (SD) age was 51 (18) weeks. Mean V'(maxFRC) (in Z score) was assessed before and after inhalation of beta(2) agonists. RESULTS: Baseline V'(maxFRC) was below reference values for both groups. Following inhalation of beta(2) agonists the mean (95% CI) change in mean V'(maxFRC) in Z scores was -0.10 (-0.26 to 0.05) and -0.33 (-0.55 to -0.11) for the malacia and wheeze group, respectively. CONCLUSIONS: In infants with wheeze, inhaled beta(2) agonists caused a significant reduction in mean V'(maxFRC). Infants with malacia were not more likely to worsen after beta(2) agonists than were infants with recurrent wheeze.

Annual lung function changes in young patients with chronic lung disease (Article)

2002-01-01T00:00:00Z

Reference equations for ventilatory function that use different statistical models may introduce artifacts that affect the estimated change of lung function during growth in young subjects. The effect of differently modelled reference equations on the estimated annual change of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in young patients with chronic lung disease was assessed. Four frequently used reference equations were used to describe the longitudinal changes of FEV1 and FVC in 52 patients (23 females) with cystic fibrosis (CF) during a mean follow-up of 3.9 yrs. Choice of reference equations directly affected value and, most importantly, estimated annual change of FVC and FEV1. Mean+/-SD annual change of FEV1 varied from 2.2+/-6.2 to -2.2+/-3.6% of predicted. For two reference equations the estimated individual changes of FEV1 and FVC in CF were positively correlated with mean individual age. This probably reflects underestimation of deteriorating lung function. Variability of annual change was independent of age only when reference equations that were designed to accurately predict lung function during the pubertal growth spurt were used. These findings have implications for patient care and clinical research.

Cartilaginous airway wall dimensions and airway resistance in cystic fibrosis lungs (Article)

2000-01-01T00:00:00Z

It is not clear how airway pathology relates to the severity of airflow obstruction and increased bronchial responsiveness in cystic fibrosis (CF) patients. The aim of this study was to measure the airway dimensions of CF patients and to estimate the importance of these dimensions to airway resistance using a computational model. Airway dimensions were measured in lungs obtained from CF patients who had undergone lung transplantation (n=12), lobectomy (n=1), or autopsy (n=4). These dimensions were compared to those of airways from lobectomy specimens from 72 patients with various degrees of chronic obstructive pulmonary disease (COPD). The airway dimensions of the CF and COPD patients were introduced into a computational model to study their effect on airway resistance. The inner wall and smooth muscle areas of peripheral CF airways were increased 3.3- and 4.3-fold respectively compared to those of COPD airways. The epithelium was 53% greater in height in peripheral CF airways. The sensitivity and maximal plateau resistance of the computed dose/response curves were substantially increased in the CF patients compared to COPD patients. The changes in airway dimensions of cystic fibrosis patients probably contribute to the severe airflow obstruction, and to increased bronchial responsiveness, in these patients.

The role of inflammation in airway disease: remodeling (Article)

2000-01-01T00:00:00Z

Aerosol delivery from spacers in wheezy infants: a daily life study (Article)

2000-01-01T00:00:00Z

The aims of this study were to assess and compare dose delivery and dose variability of pressurized metered dose inhalers (pMDI)/spacers in wheezy infants in daily life and to investigate factors influencing aerosol delivery. In an open randomized crossover study in 25 wheezy infants aged 5-26 months, a metal spacer (Nebuchamber), a detergent coated (DC) and a non-detergent coated (nonDC) plastic spacer (Babyhaler) were tested at home for 7 days each. Budesonide (200 microg b.i.d) was administered via a Nebuchamber or fluticasone (125 microg b.i.d) via a Babyhaler. Aerosol was trapped in filters, positioned between the spacer and face mask. Cooperation was scored on diary cards. Electrostatic charge (ESC) of the spacers was measured. Evaluations of the administration technique were made from video recordings. Median (range) dose delivery of the filters expressed as per cent (%) of nominal dose, was 34% (3-59), 23% (1-49), and 41% (12-55) for the Nebuchamber, nonDC-Babyhaler, and DC-Babyhaler respectively. Considerable dose variability was found, median (range) within-subject dose variability, expressed as coefficient of variation, for the Nebuchamber (49% (15-249)) was significantly higher when compared with both nonDC- (36% (12-325)) and DC-Babyhalers (27% (10-122)), for which dose variabilities were similar. Detergent coating was effective to reduce electrostatic charge, and to increase dose delivery, but had no effect on dose variability. Bad cooperation was an important cause for high dose variability for all spacers (r=0.5-0.6, p<0.02). Many mistakes were made during the administration procedure.

Variability of aerosol delivery via spacer devices in young asthmatic children in daily life (Article)

1999-01-01T00:00:00Z

Pressurized metered dose inhalers (pMDI) are widely used together with spacers for the treatment of asthma in children. However, the variability of daily medication dose for pMDI/spacer combinations is not known. Electrostatic charge is a potential source of dose variability. Metal spacers have no static charge. This study assessed and compared within-subject variability of aerosol delivery of metal and plastic spacers. This was a randomized, crossover study in children with stable asthma aged 1-4 (group I, n=17) and 5-8 (group II, n=16) yrs. In both groups the amount of drug delivered to the mouth by a metal spacer (Nebuchamber) and one of two plastic (polycarbonate) spacers, i.e. Babyhaler in group I and Volumatic in group II was measured. The metal and plastic spacers were tested at home in a randomized order for 7 days each, using budesonide (200 microg b.i.d.). Aerosol was collected on a filter positioned between spacer and facemask or mouth. Budesonide on the filter was assessed by high performance liquid chromatography. The mean filter dose for each child (mean+/-SD) during the 7 days was expressed as a percentage of the nominal dose. Within-subject variability was expressed as coefficient of variation (CV). Mean filter dose in group I was 41.7+/-10.1% for Nebuchamber and 26.0+/-4.0% for Babyhaler (p<0.001). Mean filter dose in group II was 50.2+/-9.2% for Nebuchamber and 19.4+/-7.2% for Volumatic (p<0.001). Mean CV in group I was 34% for Nebuchamber and 37% for Babyhaler (p=0.44). Mean CV in group II was 23% for Nebuchamber and 34% for Volumatic (p=0.003). There was substantial within-subject dose variability in aerosol delivery in children using a pMDI/spacer at home. This variability was lower for the metal than for the plastic spacer in children 5-8 yrs of age. The dose delivered to the mouth was about two-fold higher for the metal than the plastic spacer independent of age.

Compliance, hysteresis, and collapsibility of human small airways (Article)

1999-01-01T00:00:00Z

We tested the hypothesis that airway wall dimensions are important determinants for the mechanical properties of airways. Lung tissue was obtained from 31 smokers with different degrees of chronic obstructive pulmonary disease (COPD) who were operated on for a solitary lung lesion. Segments of small airways (n = 35) were mounted on cannulas in an organ bath and inflated and deflated cyclically between +15 and -15 cm H(2)O. For each airway this was done at baseline, after methacholine, and after isoprenaline. Specific compliance (sCdyn), specific hysteresis (seta), and pressure at which the airways collapsed (Pcol) were calculated from each recording. Airway wall dimensions were measured morphometrically. Lung function parameters of airflow obstruction were correlated to sCdyn, seta, and Pcol. At baseline, after methacholine, and after isoprenaline sCdyn was 0.059, 0.052, and 0. 085 cm H(2)O(-)(1), seta was 13.5, 12.9, and 7.1%, and Pcol was -3.4, -3.5, and -1.9 cm H(2)O, respectively. Differences between sCdyn, seta, and Pcol after methacholine and after isoprenaline were highly significant (p < 0.001). Of all dimensions studied, smooth muscle area, but not total wall area, was the most important determinant for sCdyn and for seta after methacholine. Specific hysteresis at baseline correlated to residual volume as a fraction of total lung capacity (RV/TLC) (r = 0.5, p = 0.05) and, in the presence of methacholine, to FEV(1)/FVC (r = -0.68, p = 0.02) and RV/TLC (r = 0. 5, p = 0.05). We conclude that, in this study, smooth muscle area and smooth muscle tone, but not total wall area, are determinants for compliance, hysteresis, and collapsibility of isolated airways obtained from smokers.

Structure and Function of Chronically Inflamed Human Airways of Chronically Inflamed Human Airways (Doctoral Thesis)

1998-01-21T00:00:00Z

Physiological and morphological determinants of maximal expiratory flow in chronic obstructive lung disease (Article)

1996-01-01T00:00:00Z

Maximal expiratory flow in chronic obstructive pulmonary disease (COPD) could be reduced by three different mechanisms; loss of lung elastic recoil, decreased airway conductance upstream of flow-limiting segments; and increased collapsibility of airways. We hypothesized that decreased upstream conductance would be related to inflammation and thickening of the airway walls, increased collapsibility would be related to decreased airway cartilage volume, and decreased collapsibility to inflammation and thickening of the airway walls. Lung tissue was obtained from 72 patients with different degrees of COPD, who were operated upon for a solitary peripheral lung lesion. Maximal flow-static recoil (MFSR) plots to estimate upstream resistance and airway collapsibility were derived in 59 patients from preoperatively measured maximal expiratory flow-volume and pressure-volume curves. In 341 transversely cut airway sections, airway size, airway wall dimensions and inflammatory changes were measured. Airflow obstruction correlated with lung elastic recoil and the MFSR estimate of airway conductance but not to airway collapsibility or to the amount of airway cartilage. The upstream conductance decreased as the inner wall became thicker. Airway collapsibility did not correlate with the amount of airway cartilage, inflammation, or airway wall thickness. We conclude that the maximal flow-static recoil model does not adequately reflect the collapsibility of the flow-limiting segment.