Journal of Cystic Fibrosis - Articles in Press

Increase in interleukin-8 production from circulating neutrophils upon antibiotic therapy in cystic fibrosis patients - Corrected Proof

2012-05-21

Abstract: Background: It is not known whether antibiotic therapy for lung disease in cystic fibrosis (CF) has an influence on circulating polymorphonuclear neutrophil (PMN) function and apoptosis.Patients and methods: Blood PMNs were obtained from 14 CF patients before and after antibiotic treatment for an acute exacerbation, and from 10 healthy controls. PMNs were evaluated for production of reactive oxygen species (ROS) by spectrophotometry, of cytokines in the conditioned medium by ELISA, and apoptotic response by cytofluorimetry.Results: ROS and interleukin (IL)-8 were produced at higher levels by CF PMNs pre-therapy than control PMNs under basal conditions. IL-8 levels further increased after therapy. Early apoptotic response was higher in CF PMNs pre-therapy than in control PMNs, and this pattern did not change after antibiotic treatment.Conclusions: Circulating PMNs are primed in CF acute patients. Further studies are needed to consider PMN-produced IL-8 as a biomarker to evaluate response to antibiotic therapy in CF patients.

Blood basophils from cystic fibrosis patients with allergic bronchopulmonary aspergillosis are primed and hyper-responsive to stimulation by aspergillus allergens - Corrected Proof

2012-05-18

Abstract: Introduction: Fifteen to sixty percent of cystic fibrosis patients harbor Aspergillus fumigatus (Af) in their airways (CF-AC) and some will develop allergic bronchopulmonary aspergillosis (CF-ABPA). Since basophils play a key role in allergy, we hypothesized that they would display alterations in CF-ABPA patients compared to CF-AC or patients without Af colonization (CF).Methods: Using flow cytometry, we measured CD203c, CD63 and CD123 levels on basophils from CF-ABPA (N=11), CF-AC (N=14), and CF (N=12) patients before and after ex vivo stimulation with Af allergens.Results: Baseline CD203c was increased in basophils from CF-ABPA compared to CF-AC and CF patients. Af extract and recombinant Aspf1 stimulated basophils from CF-ABPA patients to markedly upregulate CD203c, along with modest upregulation of CD63 and a CD123 downward trend. Plasma TARC/CCL17 at baseline and post-stimulation cell supernatant histamine levels were similar in the three groups.Conclusions: In CF-ABPA, blood basophils are primed and hyperresponsive to Af allergen stimulation.

Colonisation and infection of the paranasal sinuses in cystic fibrosis patients is accompanied by a reduced PMN response - Corrected Proof

2012-05-17

Abstract: Background: We studied whether the sinuses might be foci for Pseudomonas aeruginosa lung infection.Methods: Endoscopic Sinus Surgery was performed in 78 CF patients; PFGE was used for bacterial genotyping. Material from sinuses and lungs were Gram-stained to detect biofilms. Immunoglobulins were measured in serum and saliva.Results: When P. aeruginosa was cultured simultaneously from the sinuses and the lungs they were genetically identical in 38 of the 40 patients (95%). In the sinuses, P. aeruginosa formed biofilms with minimal cellular inflammation, probably because of a significantly higher local production of secretory IgA compared with IgG (p<0.001).Conclusions: We have shown that P. aeruginosa form biofilm in the sinuses, which constitute an important bacterial reservoir for subsequent lung infection. The high amount of IgA in the upper airways probably protects P. aeruginosa from the inflammatory immune system, and they can proceed unnoticed into a permanent infectious focus that cannot be eradicated with antibiotics.

Functional analysis of synonymous substitutions predicted to affect splicing of the CFTR gene - Corrected Proof

2012-05-16

Abstract: Background: Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Over 1800 CFTR mutations have been reported, and about 12% of mutations are believed to impair pre-mRNA splicing. Given that several synthetic, non-splice-junction synonymous substitutions have been reported to alter splicing in CFTR, we predicted that naturally occurring synonymous substitutions may be erroneously classified as functionally neutral.Methods: Computational tools were used to predict the effect of synonymous substitutions on CFTR pre-mRNA splicing. The functional consequences of selected substitutions were evaluated using a minigene splicing assay.Results: Two synonymous mutations were shown to have a dramatic effect on CFTR pre-mRNA splicing, and consequently could alter protein integrity and phenotypic outcome.Conclusions: Traditional methods of mutation analysis overlook splicing defects that occur at internal positions in coding exons, especially synonymous substitutions. We show that bioinformatics tools and minigene splicing assays are a potent combination to prioritize and identify mutations that cause aberrant CFTR pre-mRNA splicing.

Role of respiratory viruses in pulmonary exacerbations in children with cystic fibrosis - Corrected Proof

2012-05-14

Abstract: Background: The role of respiratory viruses in cystic fibrosis (CF) exacerbations is incompletely understood.Methods: Cross-sectional study of CF children with a pulmonary exacerbation. Mid-turbinate swabs were tested by a direct immunofluorescent antibody assay and a multiplex PCR panel (ResPlex II v2.0, Qiagen). Resplex II was also applied to sputum or throat swab samples. Pulmonary function tests and quality of life and severity scores were recorded. Sputum cell counts, bacterial density and cytokines were measured.Results: 26/43 (60.5%) subjects tested positive for at least one respiratory virus by any diagnostic method applied to any sample type. Virus-positive patients were younger (p=0.047), more likely to be male (p=0.029), and had higher CF clinical severity (p=0.041) and lower quality of life (physical) scores (p=0.023) but similar IL-8, neutrophil percentage and elastase levels.Conclusions: Compared to non-viral exacerbations, viral-related exacerbations were associated with worse severity and quality of life scores but similar pulmonary inflammation.

Validation of the Treatment Satisfaction Questionnaire for Medication in patients with cystic fibrosis - Corrected Proof

Antoine Regnault, Maria-Magdalena Balp, Károly Kulich, Muriel Viala-Danten — 2012-05-14

Abstract: Background: Our objective was to confirm the measurement properties of the Treatment Satisfaction Questionnaire with Medication (TQSM) in patients with cystic fibrosis (CF) receiving inhaled antibiotics.Methods: The TSQM was included in the EAGER study, a clinical trial comparing a nebulized and a dry powder device for inhaled tobramycin in a CF population with chronic Pseudomonas aeruginosa (Pa) lung infection, aged 6years and above (N=553). Reliability and validity of the questionnaire were investigated using Cronbach's α and multitrait–multimethod approach.Results: The TSQM demonstrated very good reliability and construct validity: all Cronbach's α were above 0.86 and all items met the convergent and discriminant validity criteria. In multivariate regressions, higher patient satisfaction and lower perceived impact of side-effects were associated with better treatment compliance.Conclusions: The TSQM showed very good measurement properties that strongly support its use to assess satisfaction of patients with CF taking inhaled antibiotics.

Risk factors for rate of decline in FEV1 in adults with cystic fibrosis - Corrected Proof

2012-05-07

Abstract: Background: Previously we assessed risk factors for FEV1 decline in children and adolescents using the Epidemiologic Study of Cystic Fibrosis (J Pediatr 2007;151:134–139); the current study assessed risk factors in adults.Methods: Risk factors for FEV1 decline over 3–5.5years for ages 18–24 and ≥25years were assessed using mixed-model regression.Results: Mean rates of FEV1 decline (% predicted/year) were −1.92 for ages 18-24y (n=2793) and −1.45 for ages ≥25y (n=1368). For the 18-24y group, B. cepacia, pancreatic enzyme use, multidrug-resistant P. aeruginosa, cough, mucoid P. aeruginosa, and female sex predicted greater decline; low baseline FEV1 and sinusitis predicted less decline. For the ≥25y group, only pancreatic enzyme use predicted greater decline; low baseline FEV1 and sinusitis predicted less decline.Conclusions: Risk factors for FEV1 decline in adults <25years are similar to those previously identified in children and adolescents; older adults had few statistically significant risk factors.

Successful treatment of cepacia syndrome with a combination of intravenous cyclosporin, antibiotics and oral corticosteroids - Corrected Proof

Francis J. Gilchrist, A. Kevin Webb, Rowland J. Bright-Thomas, Andrew M. Jones — 2012-05-03

Abstract: Burkholderia cepacia complex (BCC) is a group of 17 closely related bacterial species that can cause pulmonary infection in patients with cystic fibrosis (CF). The clinical manifestations of BCC infection are varied but can include cepacia syndrome, which is a rapidly progressing necrotising pneumonia with an almost universally fatal outcome. We report the case of a 38year old man, known to have chronic infection with the ET12 strain of Burkholderia cenocepacia who developed cepacia syndrome 26years after initial infection. Aggressive treatment with a combination of 4 intravenous antibiotics, oral corticosteroids and cyclosporin brought about clinical, radiological and biochemical resolution of his cepacia syndrome. This case highlights the possible role of cyclosporin in the treatment of cepacia syndrome.

Risk factors for age at initial Pseudomonas acquisition in the cystic fibrosis epic observational cohort - Corrected Proof

2012-05-03

Abstract: Background: Risk factors for initial Pseudomonas aeruginosa (Pa) acquisition, particularly environmental exposures, are poorly understood. We aimed to identify such risk factors in order to inform prevention strategies and identify high-risk populations.Methods: The study cohort included all participants in the U.S. EPIC Observational Study who had no prior Pa-positive respiratory cultures (N=889). Cox proportional hazard models were used to test the effects of factors on age at first Pa-positive respiratory culture.Results: Cystic fibrosis (CF) genotype functional class had an important effect on age at initial Pa acquisition (hazard ratio (HR) comparing minimal to residual CFTR function 2.87 (95% CI 1.88, 4.39)). None of the modifiable risk factors evaluated, including cigarette smoke, hot tub use, breastfeeding, or daycare, was associated with age at Pa acquisition. Similarly, newborn screening was not associated with age at Pa acquisition (HR 0.85, 95% CI 0.66, 1.09). Key associations were validated in a CF Foundation National Patient Registry replication cohort.Conclusions: Given the ubiquitous presence of Pa in the environment, it may be that many imposed lifestyle changes will have less impact on age at initial Pa acquisition than genetic determinants.

Prevalence of cystic fibrosis pathogens in the oropharynx of healthy children and implications for cystic fibrosis care - Corrected Proof

2012-05-01

Abstract: Objective: To describe the prevalence of the CF pathogens Pseudomonas aeruginosa, Staphylococcus aureus and Haemophilus influenzae in OP cultures from healthy children.Methods: Oropharyngeal (OP) swabs were collected from 100 healthy children ≤18years of age undergoing a clinically indicated procedure.Results: P. aeruginosa was isolated from the OP swab of one participant, S. aureus from 48 participants (including 4 methicillin-resistant) and H. influenzae from 47 participants. Cultures from 75 participants grew one or more of these organisms (55 grew one, 19 grew 2 and one grew 3 organisms).Conclusion: P. aeruginosa is rarely recovered from the oropharynx of healthy children ≤18years of age, while recovery of S. aureus and H. influenzae is common. It is important to understand what the “normal” prevalence of CF pathogens is in the oropharynx in order to aid interpretation of OP cultures in CF patients.

Gut dysbiosis in cystic fibrosis - Corrected Proof

2012-04-26

In people with CF, intestinal exocrine malfunction, antibiotic usage and swallowing of infected respiratory mucus likely perturb the normal community of commensal bacteria in the gut. People with CF report various intestinal problems which may be alleviated by probiotic administration . There is also evidence that probiotic bacteria can help people with CF fight respiratory infection . However, CF-related gut dysbiosis has only recently been subjected to detailed investigation. Using DGGE and culture-based methods, Duytschaever and colleagues showed that children with CF have a quantitatively and qualitatively different faecal microbiota from their healthy siblings. We conducted a pilot study using culture-independent stool microbiome profiling and found evidence consistent with these results, strengthening the case for more targeted exploration of the gut microbiota in CF.

Pilot study on the use of acoustic radiation force impulse imaging in the staging of cystic fibrosis associated liver disease - Corrected Proof

2012-04-26

Abstract: Background: Acoustic radiation force impulse (ARFI) is a novel technique for the measurement of hepatic stiffness, which could be valuable in clinical follow-up of patients affected by cystic fibrosis liver disease (CFLD).Methods: Seventy-five patients with suspected CFLD (35 males) underwent clinical and ultrasonographic evaluations, liver and pulmonary function tests, ARFI investigation, and upper gastrointestinal endoscopy. Ten ARFI measurements were taken at the deep right hepatic lobe to compute median values of Shear Wave Velocity (SWV) for each individual.Results: SWV increased progressively from 1.02m/s (95%, Confidence Interval, CI, 0.92–1.126) in patients with no evidence of CFLD at ultrasonography (N=16), to 1.12 (95%CI 1.049–1.19) in patients with CFLD and no signs of portal hypertension (PHT, N=23), and to 1.25 (95%CI 1.14–1.358) in those with CFLD and signs of PHT (N=28). SWV was 1.63 (95%CI 1.26–1.99) in patients with oesophageal varices (N=8) (p<0.0001).Conclusions: ARFI may represent an easy, fast and non-invasive tool for the clinical follow-up of patients with cystic fibrosis associated liver disease.

GUSB and ATP2B4 are suitable reference genes for CFTR gene expression data normalization in nasal epithelium cells - Corrected Proof

2012-04-23

Abstract: Background: CFTR expression studies contribute in understanding the relationship between CFTR transcripts and clinical outcomes. Normalization of qPCR data is an essential step to determine target gene expression. Consequently, appropriate reference genes must be selected for each gene/tissue. In this work, we have assessed the suitability of four potential reference genes for CFTR expression analysis in nasal epithelium.Methods: B2M, GUSB, HPRT1 and ATP2B4 expression was evaluated in nasal epithelium samples (CFTR-wt controls, n=21; CFTR-splicing group, n=18) by RT-qPCR. Calibration curves were built and different analyses (geNorm, NormFinder, Mann–Whitney) were performed to evaluate gene expression stability between samples as well as between groups.Results and conclusions: We have applied an accurate approach to select reference genes for CFTR expression analysis in nasal epithelium. From the four genes assessed, GUSB and ATP2B4 have been validated as a reliable gene combination for CFTR gene qPCR data normalization.

A phase I clinical study of inhaled nitric oxide in healthy adults - Corrected Proof

2012-04-20

Abstract: Background: Nitric oxide (NO) is an approved pulmonary vasodilator for neonates and full term infants up to a dose of 80ppm. At 100ppm to 200ppm, NO has potent antimicrobial activities in vitro and in animal studies which suggest its therapeutic use for infectious diseases in humans. However, whether inhaled NO is safe at 160ppm in healthy human adults is unknown. The aim of the phase I study was to assess the safety of delivery and the physiologic effects of intermittent 160ppm NO in healthy human adults.Methods: Ten healthy adult volunteers (5 males, 5 females; 20–62years) were recruited and inhaled 163.3ppm (SD: 4.0) NO for 30min, 5 times daily, for 5 consecutive days. Lung function and blood levels of methemoglobin, nitrites/nitrates, prothrombin, pro-inflammatory cytokines and chemokines were determined before and during treatment.Results: All individuals tolerated the NO treatment courses well. No significant adverse events occurred and three minor adverse events, not attributable to NO, were reported. Forced expiratory volume in 1sec % predicted and other lung function parameters, serum nitrites/nitrates, prothrombin, pro-inflammatory cytokine and chemokine levels did not differ between baseline and day 5, while methemoglobin increased significantly during the study period to a level of 0.9% (SD: 0.08) (p<0.001).Conclusion: These data suggest that inhalation of 160ppm NO for 30min, 5 times daily, for 5 consecutive days, is safe and well tolerated in healthy individuals.

Cystic fibrosis research in allied health and nursing professions - Corrected Proof

2012-04-19

Abstract: This report is the result of the “Allied Health and Nursing Professions Working Group” meeting which took place in Verona, Italy, November 2009, which was organised by the European Cystic Fibrosis Society, and involved 32 experts. The meeting was designed to provide a “roadmap” of high priority research questions that can be addressed by Allied Health Professionals (AHP) and nursing. The other goal was to identify research skills that would be beneficial to AHP and nursing researchers and would ultimately improve the research capacity and capability of these professions. The following tasks were accomplished: 1) a Delphi survey was used to identify high priority research areas and themes, 2) common research designs used in AHP and nursing research were evaluated in terms of their strengths and weaknesses, 3) methods for assessing the clinimetric and psychometric properties, as well as feasibility, of relevant outcome measures were reviewed, and 4) a common skill set for AHPs and nurses undertaking clinical research was agreed on and will guide the planning of future research opportunities. This report has identified important areas and themes for future research which include: adherence; physical activity/exercise; nutritional interventions; interventions for the newborn with CF and evaluation of outcome measures for use in AHP and nursing research. It has highlighted the significant challenges AHPs and nurses experience in conducting clinical research, and proposes strategies to overcome these challenges. It is hoped that this report will encourage research initiatives that assess the efficacy/effectiveness of AHP and nursing interventions in order to improve the evidence base. This should increase the quality of research conducted by these professions, justify services they currently provide, and expand their skills in new areas, with the ultimate goal of improving care for patients with CF.

LDL-cholesterol and insulin are independently associated with body mass index in adult cystic fibrosis patients - Corrected Proof

2012-04-16

Abstract: Background: The median life expectancy of cystic fibrosis (CF) patients has increased dramatically over the last few years and we now observe a subset of patients with a body mass index (BMI) exceeding 25kg/m2. The aim of this study was to characterize these individuals and to identify factors associated with higher BMI.Methods: This is a cross sectional study including 187 adult CF subjects. Percent predicted forced expiratory volume in 1s (%FEV1), blood lipid profiles as well as fasting glucose and insulin levels were evaluated. Subjects also had an oral glucose tolerance test (OGTT) and the area under the curve (AUC) for glucose and insulin was calculated. CF subjects were then stratified according to the following BMI categories: underweight: BMI≤18.5kg/m2; normal weight: 18.5kg/m2

Immunomodulatory activity of vardenafil on induced lung inflammation in cystic fibrosis mice - Corrected Proof

2012-04-13

Abstract: Background: We tested the hypothesis that vardenafil, a common drug used for improving erectile dysfunction and able to partially normalize transepithelial chloride transport in cystic fibrosis (CF), modulates CF lung inflammation.Methods: Inflammatory markers in lungs of F508del-CF and wild-type mice were monitored in response to lipopolysaccharide from Pseudomonas aeruginosa (LPS). The effect of pretreatment with vardenafil (0.14mg/kg) was evaluated.Results: A latent inflammatory status, characterized by neutrophil infiltrate, mouse macrophage inflammatory protein (MIP)-2 and tumor necrosis factor (TNF)-α, was found in baseline conditions in F508del-CF mice. Inflammatory markers were increased after LPS with higher responses in CF. Vardenafil globally attenuated inflammatory responses in both genotypes however reduction of macrophage infiltration, macrophage chemoattractant chemokine and interleukin-1β was observed in the CF group only.Conclusion: Vardenafil reduces lung inflammation with a more pronounced effect in F508del-CF mice, particularly on macrophage cell markers.

The ease of breathing test tracks clinical changes in cystic fibrosis - Corrected Proof

Traci Kazmerski, David M. Orenstein — 2012-04-11

Abstract: Introduction: The EOB is a measure of dyspnea that correlates with CF pulmonary function and exercise tolerance, but has not been shown to track clinical changes.Methods: The EOB was administered before and after treatment for twelve episodes of exacerbations in eleven pediatric CF subjects. Each subject performed the EOB Sustained Phonation and Single Breath Counting measures before and after treatment both at rest and after exercise.Results: Phonation was significantly better pre-exercise after treatment than initially (Z=−2.20, p=0.028). Phonation post-exercise was longer at follow-up than pre- antibiotics (Z=−1.91, p=0.056). Changes in post-exercise Phonation correlated significantly with changes in FEV1 before and after treatment (R=0.66, p=0.020).Conclusions: The EOB Sustained Phonation is a validated tool for tracking improvement of pediatric CF patients after antibiotic therapy and has potential as a research tool to gauge efficacy of new therapies.

Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) in Chinese patients with congenital bilateral absence of vas deferens - Corrected Proof

2012-04-09

Abstract: Background: Genetic testing of the cystic fibrosis transmembrane conductance (CFTR) gene is currently performed in patients with congenital bilateral absence of vas deferens (CBAVD). This study was conducted to investigate the role of mutations in the CFTR gene in CBAVD-dependent male infertility.Methods: 73 Chinese patients diagnosed with CBAVD were studied. The entire coding regions and splice sites of 27 exons of the CFTR gene were sequenced in 146 chromosomes from the 73 CBAVD patients. Screening was carried out using PCR, gel electrophoresis and DNA sequencing to identify novel variants of the entire coding regions and boundaries of the 27 exons.Results: Five novel nonsynonymous mutations, three novel splice site mutations and one deletion were identified by sequencing. Apart from the novel variants, we also found 19 previously reported mutations and polymorphism sites. Thirty-four patients (46.57%) had the 5T variant (6 homozygous and 28 heterozygous) and in two of them it was not associated with any detectable mutation of the CFTR gene. All potential pathogenic mutations are not contained in the 1000 Genome Project database. In total, the present study identified 30 potential pathogenic variations in the CFTR gene, 9 of which had not previously been described.Conclusions: Most patients with CBAVD have mutations in the CFTR gene. A mild genotype with one or two mild or variable mutations was observed in all the patients. These findings improve our understanding of the distribution of CFTR alleles in CBAVD patients and will facilitate the development of more sensitive CFTR mutation screening.

Right ventricular dysfunction in adolescents with mild cystic fibrosis - Corrected Proof

2012-04-09

Abstract: Background: In cystic fibrosis (CF) patients the right ventricle (RV) suffers a progressive deterioration, but it is not clear when these changes begin. The aim of this study was to analyze the RV function in CF patients with mild respiratory disease.Methods: Color-Doppler-Echocardiographic studies were prospectively performed in CF adolescent patients and an age-matched control group. Findings were correlated with pulmonary function tests (PFT), genotype, chronic bacterial colonization, pancreatic status and clinical scores. Only patients with mild CF were selected.Results: Thirty seven CF patients and 40 healthy controls were recruited. In CF patients all echocardiographic parameters were abnormal compared to controls. Doppler analysis showed slightly elevated pulmonary artery pressure values, and abnormal relaxation and systolic function for all indexes. No correlation was found with any of the features studied.Conclusions: In CF patients, abnormalities in the structure and function of the RV may be present at early stages of the disease. These abnormalities are subclinical and do not correlate with clinical scores, PFT, genotype, chronic bacterial colonization or pancreatic insufficiency.

Multiple antibiotic-resistant Pseudomonas aeruginosa and lung function decline in patients with cystic fibrosis - Corrected Proof

2012-03-26

Abstract: Background: The goal of this study was to determine the association of multiple antibiotic-resistant Pseudomonas aeruginosa (MARPA) acquisition with lung function decline in patients with cystic fibrosis (CF).Methods: Using data from Epidemiologic Study of Cystic Fibrosis (ESCF), we identified patients with spirometry data and MARPA, defined as PA (1) resistant to gentamicin and either tobramycin or amikacin, and (2) resistant to ≥1 antipseudomonal beta lactam. MARPA had to be detected in a respiratory culture after ≥2years of PA-positive but MARPA-negative respiratory cultures. Multivariable piecewise linear regression was performed to model the annual rate of decline in forced expiratory volume in 1second (FEV1) % predicted 2 calendar years before and after the index year of MARPA detection, adjusting for patient characteristics and CF therapies.Results: In total, 4349 patients with chronic PA and adequate PFT data were identified; 1111 subsequently developed MARPA, while 3238 patients were PA positive but MARPA negative. Compared with patients who did not acquire MARPA, MARPA-positive patients had lower FEV1 and received more oral (p<0.013) and inhaled (p<0.001) antibiotic therapy. Mean FEV1 decline did not change significantly after MARPA detection (−2.22% predicted/year before detection and −2.43 after, p=0.45). There was no relationship between persistent infection or FEV1 quartile and FEV1 decline.Conclusions: Newly detected MARPA was not associated with a significant change in the rate of FEV1 decline. These results suggest that MARPA is more likely to be a marker of more severe disease and more intensive therapy, and less likely to be contributing independently to more rapid lung function decline.

A heat-stable cytotoxic factor produced by Achromobacter xylosoxidans isolated from Brazilian patients with CF is associated with in vitro increased proinflammatory cytokines - Corrected Proof

Rebeca P. Mantovani, Carlos E. Levy, Tomomasa Yano — 2012-03-22

Abstract: Background: Recently, Achromobacter xylosoxidans has been related to chronic lung diseases in patients suffering from cystic fibrosis (CF), but its involvement has not been elucidated. Some virulence properties of A. xylosoxidans isolated from Brazilian patients with CF were revealed in this work.Methods: This study examined the production of a cytotoxic factor of A. xylosoxidans capable of stimulating the secretion of inflammatory cytokines (IL-6 and IL-8) from lung mucoepidermoid carcinoma cells (NCI-H292). The cytokines were measured using enzyme-linked immunosorbent (ELISA) assays. To investigate whether the cytotoxic factors may be endotoxins, they were treated with polymyxin B.Results: The culture supernatants of all A. xylosoxidans produced a heat stable, active cytotoxin in NCI-H292 cells capable of leading to intracellular vacuoles and subsequent cell contact loss, chromatin condensation, a picnotic nucleus and cell death. There was a higher concentration of proinflammatory cytokines in the NCI-H292 cells after 24h of incubation, with the fraction greater than 50kDa from the culture supernatant. The cytotoxin activity remained even after treatment with polymyxin B, which suggested that the release of IL-6 and IL-8 was not stimulated by lipopolysaccharide (LPS).Conclusion: The cytotoxic factor produced by A. xylosoxidans may represent an important virulence factor, which when associated with CF chronic lung inflammation, may cause tissue damage and decline of lung function.

Results of antibiotic susceptibility testing do not influence clinical outcome in children with cystic fibrosis - Corrected Proof

M.N. Hurley, A.H. Amin Ariff, C. Bertenshaw, J. Bhatt, A.R. Smyth — 2012-03-21

Abstract: Introduction: Patients with CF experience pulmonary exacerbations. These are often initially empirically treated with intravenous antibiotics, with antibiotic choice refined after susceptibility testing.Methods: We completed a 5-year retrospective review of children attending the Paediatric CF Unit, Nottingham. The respiratory sampling, antibiotic prescribing and susceptibility testing guidance were audited. Episodes were classified according to the concordance between the antibiotics prescribed and antibiotic susceptibility testing.Results: Of 52 patients who had previously isolated Pseudomonas aeruginosa, 103 antibiotic courses were commenced that coincided with an isolation of P. aeruginosa. P. aeruginosa was fully susceptible, partially susceptible or fully resistant on 33%, 44.7% or 16.5% of occasions respectively. The antibiotic prescriptions were never changed following antibiotic susceptibility testing. We found no association between change in FEV1 (p=0.54), change in BMI (p=0.12) or time to next exacerbation (p=0.66) and concordance between antibiotic susceptibility and the antibiotics administered.Conclusion: This study contributes to mounting evidence questioning the utility of routine antibiotic susceptibility testing.

Cost-effectiveness of carrier screening for cystic fibrosis in Australia - Corrected Proof

Richard Norman, Kees van Gool, Jane Hall, Martin Delatycki, John Massie — 2012-03-19

Abstract: Background: Carrier screening for cystic fibrosis is not widely available in Australia, partly due to concerns regarding its cost-effectiveness. The benefit of information from pregnancy to pregnancy has not been widely considered in existing cost-effectiveness analyses.Methods: A decision tree was constructed estimating costs and outcomes from screening, including both initial and subsequent pregnancies. Effectiveness was expressed in terms of CF births averted. Costs were collected using a health service perspective. All costs and outcomes were discounted at 5% per annum.Results: Screening reduced the annual incidence of CF births from 34 to 14/100,000 births (an aggregate number of CF births of 100.9 and 41.9 respectively). In initial pregnancies, costs in the screening arm (A$16.6million/100,000 births) exceed those in the non-screening arm (A$13.4million/100,000 births). The incremental cost per CF birth in initial pregnancies is therefore approximately A$150,000. However, this was reversed for subsequent pregnancies, in that the pre-collected information reduces the incidence of CF in subsequent pregnancies at low additional costs. When aggregated, the results suggest screening is likely to be cost-saving.Conclusions: The introduction of national carrier screening for cystic fibrosis should be considered, as it is likely to reduce CF incidence at an acceptable (potentially negative) cost.

Anti-inflammatory effects of DX-890, a human neutrophil elastase inhibitor - Corrected Proof

2012-03-14

Abstract: Background: Neutrophil elastase (NE)-mediated inflammation contributes to lung damage in cystic fibrosis (CF). We investigated if DX-890, a small-protein NE inhibitor, could reduce neutrophil trans-epithelial migration and reduce activity released from neutrophils and NE-induced cytokine expression in airway epithelial cells.Methods: Activated blood neutrophils (CF and healthy) treated ±DX-890 were assayed for NE activity. Transmigration of calcein-labeled neutrophils was studied using a 16HBE14o− epithelial monolayer. IL-8 release from primary nasal epithelial monolayers (CF and healthy) was measured after treatment ±DX-890 and NE or CF sputum.Results: DX-890 reduced NE activity from neutrophils (CF and healthy) and reduced neutrophil transmigration. DX-890 pre-treatment reduced IL-8 release from epithelial cells of healthy or CF subjects after stimulation with NE and CF sputum sol. All improvements with DX-890 were statistically significant (p<0.05).Conclusions: DX-890 reduces NE-mediated transmigration and inflammation. NE inhibition could be useful in managing neutrophilic airway inflammation in CF.

Bloodstream infections in cystic fibrosis: Nine years of experience in both adults and children - Corrected Proof

2012-03-14

Abstract: Background: We report the aetiology and outcome of bloodstream infections (BSI) occurring at two regional cystic fibrosis (CF) centres (one adult, one paediatric) between 1998 and 2006.Methods: A retrospective analysis of all positive blood cultures during the study period was performed.Results: During the study period 1691 blood culture sets were taken. Fifty-seven clinically significant episodes of BSI in 48 people with CF (36 adult, 12 paediatric) were identified, along with 28 other episodes considered to be contamination or not clinically significant. The most common BSIs were caused by coagulase-negative staphylococci (13) Candida spp (10), and Stenotrophomonas maltophilia (8). The majority (82%) of significant BSIs were considered to originate from totally-implantable vascular access devices (TIVADs); only 9% were attributed to the lower respiratory tract. The TIVAD was removed in two-thirds of cases of TIVAD-associated BSI. There were three deaths (60% of cases) attributable to BSI originating from the lower respiratory tract but no deaths attributable to TIVAD-associated BSI.Conclusion: Most significant BSIs in patients with CF originate from TIVADs. Targeted antimicrobial therapy and appropriate early device removal is associated with good clinical outcome. BSI originating from the lower respiratory tract is associated with poor clinical outcome.

Clinical evidence that V456A is a Cystic Fibrosis causing mutation in South Asians - Corrected Proof

L. Uppaluri, S.J. England, T.F. Scanlin — 2012-03-07

Abstract: Background: Cystic Fibrosis (CF) genotypes in South Asians are variable with a decreased incidence of Delta F508 and an increased incidence of novel mutations. The objective of this study is to provide clinical evidence that V456A, a novel mutation in South Asian Cystic Fibrosis patients, can cause significant lung disease.Methods: We extracted clinical data from a retrospective chart review of 2 CF patients of South Asian descent.Results: Patient 1, a 10year and 11month old Pakistani female at her initial clinic visit, required multiple hospitalizations for bronchiectasis and pulmonary infections. She was pancreatic sufficient but had slow weight gain. Genetic testing revealed that she is homozygous for the CFTR V456A mutation. Patient 2, an Indian female diagnosed with CF on newborn screening, is compound heterozygous for V456A/R709X. She had slow weight gain with BMI ranging from 12.9 to 13.4kg/m2 from 3 to 5years of age and was 14.2kg/m2 at 6years of age. At 6years of age, pulmonary function tests revealed mild lung disease with FVC of 71%, FEV1 of 75%, FEF25–75 of 119%, and FEV1/FVC of 86% predicted. Sputum cultures were intermittently positive for Staphylococcus aureus and Haemophilus influenza.Conclusions: We provide evidence that V456A can cause significant pulmonary disease in South Asian Cystic Fibrosis patients.

Risk factors for Mycobacterium abscessus infection in cystic fibrosis patients; a case–control study - Corrected Proof

2012-02-20

Abstract: Mycobacterium abscessus is a nontuberculous mycobacterium that is increasingly recognized as an opportunistic pathogen in cystic fibrosis (CF) patients. Factors that predispose CF patients to infection by this environmental bacterium remain unknown. In a case–control study of 22 CF patients with M. abscessus infection and 22 CF controls, we investigated risk factors for MAB infection as well as the positioning of MAB infection in relation to the other pathogens infecting CF patients. No clear risk factors were found; steroid treatment and CF related diabetes were equally common among cases and controls. M. abscessus disease affects CF patients of varying age, lung function and co-morbidities. Antimicrobial maintenance therapy did not prevent M. abscessus infection. A history of Stenotrophomonas maltophilia infection was significantly more frequent among cases than among controls and there may be a relation with Aspergillus fumigatus infection, or both may be signs of advanced lung damage that predisposes to MAB disease. The absence of clear risk factors and the omnipresence of MAB in the environment suggest that MAB infection in CF patients is a random event. Its symptoms and impact on lung function seem to warrant treatment.

The use of nebulised aztreonam lysine (AZLI) in aztreonam hypersensitive patients - Corrected Proof

P. Whitaker, C. Etherington, K. Williams, S. Conway, D. Peckham — 2012-02-20

Dear Editor, To date our experience with nebulised aztreonam lysine (AZLI) has been in patients with cystic fibrosis (CF) who have exhausted all other therapeutic options. These patients have advanced lung disease and required frequent courses of intravenous antibiotics. Unfortunately in patients with CF non-immediate hypersensitivity reactions to beta-lactam antibiotics are common. It has been reported that up to 20% of patients have multiple beta-lactam reactions . At the Regional Adult CF Unit in Leeds around 10% of patients have had a previous hypersensitivity reaction to aztreonam.

Comparison of antibiotic susceptibility patterns in Pseudomonas aeruginosa isolated from adult patients with cystic fibrosis (CF) with invasive Pseudomonas aeruginosa from non-CF patients - Corrected Proof

2012-02-13

The role of bacterial pathogens in CF pulmonary disease contributes greatly to the morbidity and mortality in patients with CF. CF patients have recurrent and chronic respiratory tract infections and most of their morbidity and mortality is due to such infections throughout their life . These infections are usually dominated by non-fermenting Gram-negative organisms (Burkholderia cenocepacia and Stenotrophomonas maltophilia), including Pseudomonas aeruginosa. P. aeruginosa is the single most important pathogen in this patient population. Recent advances in treatment, which include intensive physiotherapy and aggressive antibiotic treatment, have greatly improved the outlook for patients. However, with the improvement in survival rates in CF patients, a new range of pulmonary issues have arisen. These include the emergence of multi-drug resistant strains of P. aeruginosa and the appearance of organisms with increased virulence such as the Burkholderia cepacia complex (BCC).

Cystic fibrosis genetic counseling difficulties due to the identification of novel mutations in the CFTR gene - Corrected Proof

Myrto Poulou, Irini Fylaktou, Maria Fotoulaki, Emmanuel Kanavakis, Maria Tzetis — 2012-02-13

Abstract: Background: The Cystic Fibrosis database includes amongst the 1893 gene mutations and polymorphisms a lot of missense mutations, the disease status of which still remains unproven. In populations with high rates of CFTR mutation heterogeneity, molecular diagnosis is difficult often causing counseling difficulties especially in cases of rare and/or novel mutations.Methods: Approaches to counseling in cases of novel variants.Results: Thirty-seven novel variants (4 synonymous, 24 missense, 2 frameshift and 10 intronic substitutions) were identified and evaluated with the help of in silico tools.Conclusions: In a diagnostic environment the answers have to be given within a specific timeframe, the in silico tools in combination with the phenotype offer some help but their diagnostic value is limited and cannot be used in isolation for the determination of the severity of the mutation.

Retrospective analysis of stored dried blood spots from children with cystic fibrosis and matched controls to assess the performance of a proposed newborn screening protocol in Switzerland - Corrected Proof

2012-02-02

Abstract: Background: Newborn screening (NBS) for Cystic Fibrosis (CF) has been introduced in many countries, but there is no ideal protocol suitable for all countries. This retrospective study was conducted to evaluate whether the planned two step CF NBS with immunoreactive trypsinogen (IRT) and 7 CFTR mutations would have detected all clinically diagnosed children with CF in Switzerland.Methods: IRT was measured using AutoDELFIA Neonatal IRT-Kit in stored NBS cards.Results: Between 2006 and 2009, 66 children with CF were reported, 4 of which were excluded for various reasons (born in another country, NBS at 6months, no informed consent). 98% (61/62) had significantly higher IRT compared to matched control group. There was one false negative IRT result in an asymptomatic child with atypical CF (normal pancreatic function and sweat test).Conclusions: All children but one with atypical CF would have been detected with the planned two step protocol.