Managing cystic fibrosis: strategies that increase life expectancy and improve quality of life

Assessment of CF lung disease using motion corrected PROPELLER MRI: a comparison with CT

OBJECTIVES

To date, PROPELLER MRI, a breathing-motion-insensitive technique, has not been assessed for cystic fibrosis (CF) lung disease. We compared this technique to CT for assessing CF lung disease in children and adults.

METHODS

Thirty-eight stable CF patients (median 21 years, range 6-51 years, 22 female) underwent MRI and CT on the same day. Study protocol included respiratory-triggered PROPELLER MRI and volumetric CT end-inspiratory and -expiratory acquisitions. Two observers scored the images using the CF-MRI and CF-CT systems. Scores were compared with intra-class correlation coefficient (ICC) and Bland-Altman plots. The sensitivity and specificity of MRI versus CT were calculated.

RESULTS

MRI sensitivity for detecting severe CF bronchiectasis was 0.33 (CI 0.09-0.57), while specificity was 100% (CI 0.88-1). ICCs for bronchiectasis and trapped air were as follows: MRI-bronchiectasis (0.79); CT-bronchiectasis (0.85); MRI-trapped air (0.51); CT-trapped air (0.87). Bland-Altman plots showed an MRI tendency to overestimate the severity of bronchiectasis in mild CF disease and underestimate bronchiectasis in severe disease.

CONCLUSIONS

Motion correction in PROPELLER MRI does not improve assessment of CF lung disease compared to CT. However, the good inter- and intra-observer agreement and the high specificity suggest that MRI might play a role in the short-term follow-up of CF lung disease (i.e. pulmonary exacerbations).

KEY POINTS

PROPELLER MRI does not match CT sensitivity to assess CF lung disease. PROPELLER MRI has lower sensitivity than CT to detect severe bronchiectasis. PROPELLER MRI has good to very good intra- and inter-observer variability. PROPELLER MRI can be used for short-term follow-up studies in CF.

Early chronic obstructive pulmonary disease: definition, assessment, and prevention

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. COPD, however, is a heterogeneous collection of diseases with differing causes, pathogenic mechanisms, and physiological effects. Therefore a comprehensive approach to COPD prevention will need to address the complexity of COPD. Advances in the understanding of the natural history of COPD and the development of strategies to assess COPD in its early stages make prevention a reasonable, if ambitious, goal.

Consensus statement on preventive and symptomatic care of leukodystrophy patients

Leukodystrophies are inherited disorders whose primary pathophysiology consists of abnormal deposition or progressive disruption of brain myelin. Leukodystrophy patients manifest many of the same symptoms and medical complications despite the wide spectrum of genetic origins. Although no definitive cures exist, all of these conditions are treatable. This report provides the first expert consensus on the recognition and treatment of medical and psychosocial complications associated with leukodystrophies. We include a discussion of serious and potentially preventable medical complications and propose several preventive care strategies. We also outline the need for future research to prioritize clinical needs and subsequently develop, validate, and optimize specific care strategies.

The findings of a clinical surveillance bronchoalveolar lavage programme in pre-school patients with cystic fibrosis

BACKGROUND

Evidence suggests infection is present in the lower airways of young children with cystic fibrosis (CF), even when clinically stable. Oropharyngeal samples (OPS) are typically used for airway surveillance in these children but have been shown to have low positive predictive values and low sensitivity in detecting lower airway infection when compared with the reference standard, bronchoalveolar lavage (BAL).

METHODS

The aim of this study was to determine the prevalence of pathogens in lower airway samples detected as part of a pilot clinical BAL surveillance programme, in young children aged from one to six years old, and to ascertain if their detection resulted in a change in treatment.

RESULTS

During the study 78 bronchoscopies were performed on 38 patients. The average age at the time of bronchoscopy was 2.7 years (range 0.3-7.0 year). A significant organism was detected in 58 (74.5%) BALs. Haemophilus influenzae was detected in 27 (34.6%) samples, 16 (20.5%) samples had Staphylococcus aureus, and nine (11.5%) had Pseudomonas aeruginosa. Change in treatment occurred after 46 (58.9%) BALs.

CONCLUSIONS

This study suggests that, in young non-expectorating children with CF, routine surveillance bronchoscopy allows the detection of significant lower airway pathogens and provides the opportunity for targeted treatment of sub-clinical infection.

Mapping the EQ-5D index from the cystic fibrosis questionnaire-revised using multiple modelling approaches

Background

This study was designed to develop a mapping algorithm to estimate EQ-5D utility values from Cystic Fibrosis Questionnaire-Revised (CFQ-R) data.

Methods

A cross-sectional survey of adults with cystic fibrosis (CF) was conducted in the UK. The survey consisted of the CFQ-R, the EQ-5D and a background questionnaire. Eight regression models, exploring item and domain level predictors, were evaluated using three different modelling approaches: ordinary least squares (OLS), Tobit, and a two-part model (TPM). Predictive performance in each model was assessed by intraclass correlations, information criteria (Bayesian information criteria and Alkaike information criteria), and root mean square error (RMSE).

Results

The survey was completed by 401 participants. For all modelling approaches the best performing item level model included all items, and the best performing domain level model included the CFQ-R Physical-, Role- and Emotional-functioning, Vitality, Eating Disturbances, Weight, and Digestive Symptoms domains and a selection of squared terms. Overall, the item level TPM, including age and gender covariates performed best within sample validation, but OLS and TPM domain models with squared terms performed best out-of-sample and are recommended for mapping purposes.

Conclusions

Domain and item level models using all three modelling approaches reached an acceptable degree of predictive performance with domain models performing well in out-of-sample validation. These mapping functions can be applied to CFQ-R datasets to estimate EQ-5D utility values for economic evaluations of interventions for patients with cystic fibrosis. Further research evaluating model performance in an independent sample is encouraged.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-015-0224-6) contains supplementary material, which is available to authorized users.

Genetic diseases conferring resistance to infectious diseases

This review considers available evidence for mechanisms of conferred adaptive advantages in the face of specific infectious diseases. In short, we explore a number of genetic conditions, which carry some benefits in adverse circumstances including exposure to infectious agents. The examples discussed are conditions known to result in resistance to a specific infectious disease, or have been proposed as being associated with resistance to various infectious diseases. These infectious disease—genetic disorder pairings include malaria and hemoglobinopathies, cholera and cystic fibrosis, tuberculosis and Tay-Sachs disease, mycotic abortions and phenylketonuria, infection by enveloped viruses and disorders of glycosylation, infection by filoviruses and Niemann–Pick C1 disease, as well as rabies and myasthenia gravis. We also discuss two genetic conditions that lead to infectious disease hypersusceptibility, although we did not cover the large number of immunologic defects leading to infectious disease hypersusceptibilities. Four of the resistance-associated pairings (malaria/hemogloginopathies, cholera/cystic fibrosis, tuberculosis/Tay-Sachs, and mycotic abortions/phenylketonuria) appear to be a result of selection pressures in geographic regions in which the specific infectious agent is endemic. The other pairings do not appear to be based on selection pressure and instead may be serendipitous. Nonetheless, research investigating these relationships may lead to treatment options for the aforementioned diseases by exploiting established mechanisms between genetically affected cells and infectious organisms. This may prove invaluable as a starting point for research in the case of diseases that currently have no reliably curative treatments, e.g., HIV, rabies, and Ebola.

Novel personalized therapies for cystic fibrosis: treating the basic defect in all patients

Cystic fibrosis (CF) is the most common genetic life-shortening condition in Caucasians. Despite being a multi-organ disease, CF is classically diagnosed by symptoms of acute/chronic respiratory disease, with persistent pulmonary infections and mucus plugging of the airways and failure to thrive. These multiple symptoms originate from dysfunction of the CF transmembrane conductance regulator (CFTR) protein, a channel that mediates anion transport across epithelia. Indeed, establishment of a definite CF diagnosis requires proof of CFTR dysfunction, commonly through the so-called sweat Cl(-) test. Many drug therapies, including mucolytics and antibiotics, aim to alleviate the symptoms of CF lung disease. However, new therapies to modulate defective CFTR, the basic defect underlying CF, have started to reach the clinic, and several others are in development or in clinical trials. The novelty of these therapies is that, besides targeting the basic defect underlying CF, they are mutation specific. Indeed, even this monogenic disease is influenced by a large number of different genes and biological pathways as well as by environmental factors that are difficult to assess. Accordingly, every person with CF is unique and so functional assessment of patients' tissues ex vivo is key for diagnosing and predicting the severity of this disease. Of note, such assessment will also be crucial to assess drug responses, in order to effectively treat all CF patients. It is not because it is a monogenic disorder that personalized treatment for CF is much easier than for complex disorders.

Protein is an important but undervalued macronutrient in the nutritional care of patients with cystic fibrosis

PURPOSE OF REVIEW

Achieving an optimal nutritional status in patients with cystic fibrosis (CF) is important to maintain better pulmonary function, physical performance, and to prolong survival. So far, nutrition care in CF has mainly focused on fat intake and achieving energy balance, but there is increasing information on the clinical importance of muscle maintenance and protein intake in CF.

RECENT FINDINGS

Low muscle mass is consistently associated with pulmonary decline, bone mineral loss, and poor survival in CF. High energy and fat intake contributes to an increased prevalence of overweight and obesity in CF. Obesity per se is not related to better lung function in CF and has negative metabolic and clinical consequences, particularly when muscle wasting is present. Protein digestion capacity is severely impaired in CF, but high protein intake is needed and essential amino acid mixtures appear highly anabolic even in those with severe muscle loss.

SUMMARY

Body composition assessment and achieving protein balance in the routine care in CF is important to prevent muscle loss and further improve the clinical and overall outcome of these patients. New approaches are needed to optimize the interaction between high essential amino-acid-rich protein intake and pancreatic enzyme regimen in CF. The optimal level of protein intake needs to be assessed in clinically stable CF patients as well as in those recovering from an acute exacerbation.

Pseudomonas aeruginosa eradicates Staphylococcus aureus by manipulating the host immunity

Young cystic fibrosis (CF) patients' airways are mainly colonized by Staphylococcus aureus, while Pseudomonas aeruginosa predominates in adults. However, the mechanisms behind this infection switch are unclear. Here, we show that levels of type-IIA-secreted phospholipase A2 (sPLA2-IIA, a host enzyme with bactericidal activity) increase in expectorations of CF patients in an age-dependent manner. These levels are sufficient to kill S. aureus, with marginal effects on P. aeruginosa strains. P. aeruginosa laboratory strains and isolates from CF patients induce sPLA2-IIA expression in bronchial epithelial cells from CF patients (these cells are a major source of the enzyme). In an animal model of lung infection, P. aeruginosa induces sPLA2-IIA production that favours S. aureus killing. We suggest that sPLA2-IIA induction by P. aeruginosa contributes to S. aureus eradication in CF airways. Our results indicate that a bacterium can eradicate another bacterium by manipulating the host immunity.

Advances in the diagnosis and treatment of cystic fibrosis

CF is a genetic, life-shortening, multisystem disease that is most commonly diagnosed through newborn screen performed in all 50 states in the United States. In the past, therapies for CF lung disease have primarily targeted the downstream effects of a dysfunctional CFTR protein. Newer CFTR modulator therapies, targeting the basic defect in CF, are available for a limited group of people with CF, and offer the hope of improved treatment options for many more people with CF in the near future. Best practice is directed by consensus clinical care guidelines from the CFF and is provided with a multidisciplinary approach by the team at the CF care center and the primary care office.

Pyrosequencing reveals transient cystic fibrosis lung microbiome changes with intravenous antibiotics

Chronic airway infection in adults with cystic fibrosis (CF) is polymicrobial and the impact of intravenous antibiotics on the bacterial community composition is poorly understood. We employed culture-independent molecular techniques to explore the early effects of i.v. antibiotics on the CF airway microbiome.

DNA was extracted from sputum samples collected from adult subjects with CF at three time-points (before starting treatment, and at day 3 and day 8–10 of i.v. antibiotics) during treatment of an infective pulmonary exacerbation. Microbial community profiles were derived through analysis of bacterial-derived 16S ribosomal RNA by pyrosequencing and changes over time were compared.

59 sputum samples were collected during 24 pulmonary exacerbations from 23 subjects. Between treatment onset and day 3 there was a significant reduction in the relative abundance of Pseudomonas and increased microbial diversity. By day 8–10, bacterial community composition was similar to pre-treatment. Changes in community composition did not predict improvements in lung function.

The relative abundance of Pseudomonas falls rapidly in subjects with CF receiving i.v. antibiotic treatment for a pulmonary exacerbation and is accompanied by an increase in overall microbial diversity. However, this effect is not maintained beyond the first week of treatment.

Eltgol acutelly improves airway clearance and reduces static pulmonary volumes in adult cystic fibrosis patients

Chest physical therapy techniques are essential in order to reduce the frequency of recurrent pulmonary infections that progressively affect lung function in cystic fibrosis patients. Recently, ELTGOL (L’Expiration Lente Totale Glotte Ouverte en décubitus Latéral) emerged as an inexpensive and easy to perform therapeutic option. The aim of this study was to compare the acute effects of ELTGOL and the Flutter valve in stable adult patients with cystic fibrosis. [Subjects and Methods] This was a randomized, crossover study with a sample of cystic fibrosis outpatients. The subjects underwent two protocols (Flutter Valve and ELTGOL interventions, referred to as ELTGOL and FLUTTER) in a randomized order with a one-week washout interval between them. The main outcomes were pulmonary function variables and expectorated sputum dry weight. [Results] ELTGOL cleared 0.34 g more of secretions than FLUTTER (95% CI 0.11 to 0.57). When comparing the physiological effects of ELTGOL and FLUTTER, the first was superior in improving airway resistance (−0.51 cmH₂O/L/s; 95% CI −0.88 to −0.14) and airway conductance (0.016 L/s/cmH₂O; 95% CI 0.008 to 0.023). [Conclusion] ELTGOL promoted higher secretion removal and improvement in airway resistance and conductance than the Flutter valve. These techniques were equivalent in reducing the pulmonary hyperinflation and air trapping in cystic fibrosis patients.

Vitamin D as an anti-microbial and anti-inflammatory therapy for Cystic Fibrosis

Cystic fibrosis (CF) is characterized by chronic infection and inflammation in the airways that lead to progressive lung damage and early death. Current anti-inflammatory therapies are limited by extensive adverse effects or insufficient efficacy. There is a large body of studies indicating beneficial anti-microbial and anti-inflammatory properties of vitamin D. Since most patients with CF present with vitamin D deficiency, and serum vitamin D levels demonstrate a positive correlation with lung function and negative correlation with airway inflammation and infection, correcting vitamin D deficiency may be an attractive therapeutic strategy in CF. The function of vitamin D is intricately tied to its metabolism, which may be impaired at multiple steps in patients with CF, with a potential to limit the efficacy of vitamin D supplementation. It is likely that the aforementioned beneficial properties of vitamin D require supplementation with doses of vitamin D markedly higher than those recommended to maintain proper bone function. This review will illustrate the potential for supplementation with vitamin D or its metabolites to modulate inflammation and improve defence against chronic infection in CF lung, as well as appropriate vitamin D supplementation strategies for improving lung function in CF.

Release of cystic fibrosis airway inflammatory markers from Pseudomonas aeruginosa-stimulated human neutrophils involves NADPH oxidase-dependent extracellular DNA trap formation

Cystic fibrosis (CF) airways are characterized by bacterial infections, excess mucus production, and robust neutrophil recruitment. The main CF airway pathogen is Pseudomonas aeruginosa. Neutrophils are not capable of clearing the infection. Neutrophil primary granule components, myeloperoxidase (MPO) and human neutrophil elastase (HNE), are inflammatory markers in CF airways, and their increased levels are associated with poor lung function. Identifying the mechanism of MPO and HNE release from neutrophils is of high clinical relevance for CF. In this article, we show that human neutrophils release large amounts of neutrophil extracellular traps (NETs) in the presence of P. aeruginosa. Bacteria are entangled in NETs and colocalize with extracellular DNA. MPO, HNE, and citrullinated histone H4 are all associated with DNA in Pseudomonas-triggered NETs. Both laboratory standard strains and CF isolates of P. aeruginosa induce DNA, MPO, and HNE release from human neutrophils. The increase in peroxidase activity of neutrophil supernatants after Pseudomonas exposure indicates that enzymatically active MPO is released. P. aeruginosa induces a robust respiratory burst in neutrophils that is required for extracellular DNA release. Inhibition of the cytoskeleton prevents Pseudomonas-initiated superoxide production and DNA release. NADPH oxidase inhibition suppresses Pseudomonas-induced release of active MPO and HNE. Blocking MEK/ERK signaling results in only minimal inhibition of DNA release induced by Pseudomonas. Our data describe in vitro details of DNA, MPO, and HNE release from neutrophils activated by P. aeruginosa. We propose that Pseudomonas-induced NET formation is an important mechanism contributing to inflammatory conditions characteristic of CF airways.

Preventable Infections in Children with Leukodystrophy

Children with inherited leukodystrophies have high hospitalization rates, often associated with infection. We studied whether potentially modifiable risk factors (pre-existing in-dwelling central intravenous access, urinary catheter, hardware, or mechanical ventilation; and influenza vaccine) were associated with infection-related hospitalization in children with leukodystrophy. Central intravenous access was associated with sepsis (odds ratio (OR) 9.8); urinary catheter was associated with urinary tract infections (OR 9.0); lack of seasonal vaccination was associated with influenza (OR 6.4); and mechanical ventilation was associated with pneumonia (OR 2.7). We conclude that potentially modifiable risk factors are significantly associated with infection and hospitalization in children with leukodystrophies.

An automated integrated platform for rapid and sensitive multiplexed protein profiling using human saliva samples

During the last decade, saliva has emerged as a potentially ideal diagnostic biofluid for noninvasive testing. In this paper, we present an automated, integrated platform useable by minimally trained personnel in the field for the diagnosis of respiratory diseases using human saliva as a sample specimen. In this platform, a saliva sample is loaded onto a disposable microfluidic chip containing all the necessary reagents and components required for saliva analysis. The chip is then inserted into the automated analyzer, the SDReader, where multiple potential protein biomarkers for respiratory diseases are measured simultaneously using a microsphere-based array via fluorescence sandwich immunoassays. The results are read optically, and the images are analyzed by a custom-designed algorithm. The fully automated assay requires as little as 10 μL of saliva sample, and the results are reported in 70 min. The performance of the platform was characterized by testing protein standard solutions, and the results were comparable to those from the 3.5 h lab bench assay that we have previously reported. The device was also deployed in two clinical environments where 273 human saliva samples collected from different subjects were successfully tested, demonstrating the device's potential to assist clinicians with the diagnosis of respiratory diseases by providing timely protein biomarker profiling information. This platform, which combines noninvasive sample collection and fully automated analysis, can also be utilized in point-of-care diagnostics.

Contamination of hypertonic saline solutions in use by cystic fibrosis patients in Israel

BACKGROUND

Treatment of cystic fibrosis (CF) patients with inhaled hypertonic saline (HS) solutions is safe, beneficial and reduces exacerbation rates. We studied contamination of solutions used by Israeli CF patients for prolonged periods.

METHODS

The study addressed whether daily opening of previously unopened solutions caused contamination, survival of 6 CF-associated bacteria in artificially inoculated solutions, in-use contamination of solutions and patterns of their use by patients.

RESULTS

Repeated opening did not contaminate solutions and survival of indicator bacteria was variable. Mycobacterium abscessus survived in 3% HS solution for 6 weeks and Burkholderia cenocepacia and Pseudomonas aeruginosa were longer. In 30/76 (39.5%) of used solutions 49 contaminants were found, none being common CF-associated pathogens.

CONCLUSIONS

Most CF-related bacteria survived to some degree in HS. Approximately 40% of solutions used by patients were contaminated by organisms of uncertain significance. Our findings highlight the potential risk posed by contamination of HS solutions and support recommendations to use sterile unit-dose formulations.

The relative frequency of CFTR mutation classes in European patients with cystic fibrosis

More than 1900 different mutations in the CFTR gene have been reported. These are grouped into classes according to their effect on the synthesis and/or function of the CFTR protein. CFTR repair therapies that are mutation or mutation class specific are under development. To progress efficiently in the clinical phase of drug development, knowledge of the relative frequency of CFTR mutation classes in different populations is useful. Therefore, we describe the mutation class spectrum in 25,394 subjects with CF from 23 European countries. In 18/23 countries, 80% or more of the patients had at least one class II mutation, explained by F508del being by far the most frequent mutation. Overall 16.4% of European patients had at least one class I mutation but this varied from 3 countries with more than 30% to 4 countries with less than 10% of subjects. Overall only respectively 3.9, 3.3 and 3.0% of European subjects had at least one mutation of classes III, IV and V with again great variability: 14% of Irish patients had at least one class III mutation, 7% of Portuguese patients had at least one class IV mutation, and in 6 countries more than 5% of patients had at least one class V mutation.

Outpatient endoscopic sinus surgery in cystic fibrosis patients: predictive factors for admission

BACKGROUND

An increasing number of adult patients with cystic fibrosis (CF) are becoming candidates for elective endoscopic sinus surgery (ESS). We sought to identify perioperative factors in this patient population that were predictive of postoperative admission.

METHODS

Retrospective chart review of CF patients who underwent ESS during the years 2005 through 2012. Multiple preoperative, intraoperative, and immediate postoperative variables were analyzed.

RESULTS

Thirty-three patients who underwent 37 outpatient ESSs were identified. Successful same-day discharge was observed in 54%. In 46% of cases, postoperative admission was necessary, with a mean postoperative stay of 1.4 days. Pulmonary function, CF-related comorbidities, and history of lung transplant were not predictors of postoperative admission. Univariate analysis demonstrated that patients were more likely to be admitted if they had 1 of the following conditions: history of ≥4 prior ESS; procedure duration >2.5 hours; intraoperative blood loss greater than 150 mL; increased immediate postoperative pain scores; or larger narcotic requirements for pain control. On logistic regression analysis, a maximum pain score ≥ 7 out of 10 in the postanesthesia recovery unit was the only significant predisposing factor for postoperative admission.

CONCLUSION

Although over 50% of adult CF patients can successfully undergo ESS on a same-day discharge basis, it is prudent to have contingent plans for potential inpatient observation postoperatively. Multivariate analysis suggests that preoperative demographics and pulmonary status cannot predict the need for postoperative admission, whereas higher pain scores in the postanesthesia care unit are predictive of the necessity for inpatient observation.

Parent and child perceptions of a self-regulated, home-based exercise program for children with cystic fibrosis

BACKGROUND

Despite recognized benefits, many children with cystic fibrosis (CF) do not consistently participate in physical activities. There is little empirical literature regarding the feelings and attitudes of children with CF toward exercise programs, parental roles in exercise, or factors influencing exercise experiences during research participation.

OBJECTIVES

The aim of this study is to describe the exercise experiences of children with CF and their parents during participation in a 6-month program of self-regulated, home-based exercise.

METHODS

This qualitative descriptive study was nested within a randomized controlled trial of a self-regulated, home-based exercise program and used serial semistructured interviews conducted individually at 2 and 6 months with 11 purposively selected children with CF and their parent(s).

RESULTS

Six boys and five girls, ages 10-16 years, and parents(nine mothers, four fathers) participated in a total of 44 interviews. Five major thematic categories describing child and parent perceptions and experience of the bicycle exercise program were identified in the transcripts: (a) motivators, (b) barriers, (c) effort/work, (d) exercise routine, and (e) sustaining exercise. Research participation, parent-family participation, health benefits, and the child's personality traits were the primary motivators. Competing activities, priorities, and responsibilities were the major barriers in implementing the exercise program as prescribed. Motivation waned, and the novelty wore off for several (approximately half) parent-child dyads, who planned to decrease or stop the exercise program after the study ended.

DISCUSSION

We identified motivators and barriers to a self-regulated, home-based exercise program for children with CF that can be addressed in planning future exercise interventions to maximize the health benefits for children with CF and the feasibility and acceptability to the children and their families.

HRCT and MRI of the lung in children with cystic fibrosis: comparison of different scoring systems

BACKGROUND

Chest imaging is essential in the assessment of respiratory disease in cystic fibrosis (CF). High-resolution computed tomography (HRCT) can detect progressive lung disease but involves significant delivered dose of ionizing radiation. Magnetic resonance imaging (MRI) is radiation-free but is rarely used in CF. Based on the limited information on the potential interest of chest MRI in CF pediatric patients, the aims of our study were: 1) to evaluate and compare the reproducibility of HRCT and MRI scores; and 2) to evaluate the agreement between HRCT and MRI scores using both Helbich and Eichinger scores.

METHODS

In this prospective study, CF children who were having a HRCT for their routine assessment were proposed to perform a chest MRI the same day. 17 patients were included (median age 12.7 years). Two radiologists scored independently HRCT (Helbich score) and MRI (Helbich and Eichinger scores); and established a consensus score. Concordance was assessed using the Intraclass Correlation Coefficient (ICC); and the inter-observer reproducibility between methods was compared using Fisher's Z test for dependent observations.

RESULTS

Concordance between readers was almost perfect for HRCT score (ICC = 96%) and MRI-Eichinger score (84%), and substantial for MRI-Helbich score (68%). Correlation was strong between HRCT and MRI (r = 0.86 and 0.91 for HRCT and respectively MRI-Eichinger and MRI-Helbich scores) and the concordance almost perfect and substantial (ICC = 86% and 78% for HRCT and respectively MRI-Eichinger and MRI-Helbich scores).

CONCLUSIONS

We showed that, in CF children, MRI could adequately visualize lung morphologic changes when compared with the "gold-standard" HRCT. Regarding the potential cancer risks from associated ionizing radiation with HRCT, these results lead us to propose larger intervals of time between two lung HRCTs with realization of lung MRI in the meantime.

Development, clinical utility, and place of ivacaftor in the treatment of cystic fibrosis

Cystic fibrosis (CF) is a life-limiting, multisystem disease characterized by thick viscous secretions leading to recurrent lung infections, bronchiectasis, and progressive deterioration in lung function. CF is caused by loss or dysfunction of the CF transmembrane conductance regulator (CFTR) protein which is responsible for transepithelial chloride and water transport. Improved understanding of CFTR protein dysfunction has allowed the development of mutation-specific small-molecule compounds which directly target the underlying CFTR defect. Ivacaftor is the first licensed small-molecule compound for CF patients which targets the CFTR gating mutation Gly551Asp (previously termed G551D) and has the potential to be truly disease-modifying. Ivacaftor is an oral medication given twice daily and has shown benefit in terms of an increase in lung function, decreased sweat chloride, weight gain, improvement in patient-reported quality of life, and reduction in number of respiratory exacerbations in clinical trials. Although ivacaftor is currently only licensed for use in approximately 5% of the CF population (those who have at least one Gly551Asp mutation), the developmental pathway established by ivacaftor paves the way for other CFTR modulators that may benefit many more patients. In particular, a CFTR modulator for those with the Phe508del deletion (previously ∆F508) would allow 90% of the CF population to benefit from disease-modifying treatment.

Increased adherence to CFF practice guidelines for pulmonary medications correlates with improved FEV1

BACKGROUND

CFF practice guidelines recommend patients ≥age 6 use dornase alfa and hypertonic saline daily, and those ≥age 6 colonized with Pseudomonas aeruginosa use inhaled tobramycin and oral azithromycin to improve lung function and reduce pulmonary exacerbations. A decline in FEV1 was noted in our 2008 CF Center Report. We hypothesized that increasing adherence to prescribing guidelines for these pulmonary medications would improve mean FEV1.

METHODS

This was a quality improvement project completed at a US CF center. CFF practice guidelines were reviewed with the center physicians. Patients were identified that were eligible to receive recommended therapies and it was determined whether they were prescribed the therapies. Baseline FEV1 data was collected. Adherence rates and FEV1 were followed quarterly for 1 year. Providers received a quarterly report card with adherence rates, mean FEV1 compared to colleagues, and a list of eligible patients that were not prescribed recommended therapies.

RESULTS

Ninety-two patients were included. At baseline, the overall adherence rate was 59%. Overall adherence increased quarterly (P = < 0.001). Each quarter there was improvement in adherence to prescribing for each medication (P < 0.001). Except in quarter 1, FEV1 increased quarterly (P = 0.092). There was moderate correlation (r = 0.533) between improved adherence and improved FEV1.

CONCLUSIONS

Educating clinicians about guidelines, providing feedback on adherence to guidelines, and monitoring prescribing patterns improves prescribing adherence. FEV1 showed improvement after months of sustained adherence, trending towards significance. Longer follow-up is necessary to determine if improved prescribing adherence translates into improved FEV1 or slows rate of decline in FEV1.

Tobramycin inhalation powder manufactured by improved process in cystic fibrosis: the randomized EDIT trial

BACKGROUND

Tobramycin inhalation powder (TIP) was reported to be effective in two Phase III studies in patients with cystic fibrosis (CF) chronically infected with Pseudomonas aeruginosa (Pa). The EDIT study evaluated the efficacy and safety of TIP manufactured by an improved process in CF subjects aged 6-21 years.

METHODS

CF patients with a forced expiratory volume in 1 second (FEV₁) ≥25% to ≤80% predicted, positive Pa cultures and inhaled antipseudomonal therapy naïve (or at least for past 4 months) were enrolled into this double-blind, multicenter trial. Patients were randomized to receive TIP or placebo (1:1) twice daily for one treatment cycle (28.5 days on drug, 28 days off drug). The primary endpoint was relative change in FEV₁ percentage predicted from baseline to day 29. A pre-specified sensitivity analysis evaluated absolute change in FEV₁% predicted. Other endpoints included Pa sputum density and safety.

RESULTS

A total of 62 patients out of a target of 100 (mean age 12.9 years, baseline FEV₁ 59.2% predicted, Pa sputum density 7.4 log₁₀ colony forming units [CFU] per gram) were randomized. Mean treatment differences (TIP - placebo) were 5.9% (p=0.148) and 4.4% (p<0.05) for relative and absolute change in FEV₁% predicted respectively. TIP significantly reduced Pa sputum density by -1.2 log10 CFU (p=0.002). Treatment with TIP was well tolerated.

CONCLUSIONS

Relative change in FEV₁% predicted with TIP treatment was in the expected range based on the literature, but did not reach statistical significance versus placebo. Placebo control and use of treatment naïve patients led to significant recruitment challenges and an underpowered study with consequent impact on the generated data. However, significant improvements in other outcomes including absolute change in FEV₁% predicted and reduction in Pa sputum density indicate that TIP is efficacious and well tolerated in CF patients. CLINICALTRIALS.GOV IDENTIFIER: NCT00918957.

Modification of the salivary secretion assay in F508del mice--the murine equivalent of the human sweat test

BACKGROUND

In 2005 Best and Quinton established the salivary secretion assay in mice for the in vivo characterization of new drugs against cystic fibrosis (CF). However, limited data are available and the predictive value of this in vivo assay for treatment effects in CF patients is not fully understood.

METHODS

Therefore, we revisited the salivary secretion assay and systematically investigated the salivary secretion rates in different murine backgrounds and sexes, as well as in different CF mouse models. Moreover, we established quantification of salivary chloride content.

RESULTS

We found a strain- and sex-dependency of salivary secretion rates and were able to confirm the decreased β-adrenergic salivary secretion response in CFTR knockout mice (CFTR(tm1Unc)) as well as in the F508del CFTR mice of different origins (CFTR(tm1Kth) and CFTR(tm1Eur)). In heterozygous Cftr+/- and Cftr+/F508del mice, the isoprenaline-stimulated salivary secretion rate and the Cl(-) content were intermediate between values measured in WT and CF mice, indicating that this assay is also able to detect CF carriership. Pilocarpine-induced abnormalities in saliva chloride content in CF mice resembled the changes observed in the human sweat test.

CONCLUSIONS

Determination of murine salivary chloride content in combination with salivary secretion rate in CF mice may render the salivary secretion assay as a powerful tool for validation of new CF treatments.

Mitochondrial OXPHOS function is unaffected by chronic azithromycin treatment

BACKGROUND

Certain antibiotics may cause unwanted side effects due to the similarity of the mitochondrial translation system to the prokaryotic one. Children with cystic fibrosis (CF) are vulnerable to recurrent respiratory tract infections and azithromycin, a translation targeted antibiotic, is often used chronically to treat CF patients. No major clinical side effects were found with chronic treatment. However, mitochondrial function was not previously assessed. We evaluated oxidative phosphorylation (OXPHOS) in lymphocytes from children with CF receiving chronic azithromycin treatment using an improved ATP production assay.

METHOD

Enzymatic activities of respiratory chain complexes II-IV and ATP production were measured in lymphocytes.

RESULTS

Relative to controls and to CF patients without azithromycin treatment, no significant difference in mitochondrial respiratory chain complexes II-IV was detected, and ATP production with pyruvate, glutamate and succinate, did not disclose any differences between the groups.

CONCLUSION

We suggest that chronic treatment with azithromycin does not significantly affect OXPHOS function.

Change in health status and access to care in young adults with special health care needs: results from the 2007 national survey of adult transition and health

BACKGROUND

Despite over 500,000 adolescents with special health care needs transitioning to adulthood each year, limited information is available on their health status or their access to care after transition.

OBJECTIVE

To describe the change in health status and access to care of a nationally sampled, longitudinal cohort of young adults with special health care needs (ASHCN).

METHODS

We analyzed follow-up data collected in the 2007 Survey of Adult Transition and Health on young adults who were 14-17 years of age when their parents participated in the 2001 National Survey of Children with Special Health Care Needs. We describe changes in access to care and health status over time, and used logistic regression to identify characteristics that were associated with declining health status in this cohort.

RESULTS

1,865 participants, aged 19-23 years, completed the Survey of Adult Transition and Health. Between 2001 and 2007, there was a 3.6 fold increase in the proportion experiencing delayed or forgone care; 10% reported a decline in health status. There was a 7.7-fold increase in the proportion reporting no insurance. In regression analysis, factors associated with declining health status between 2001 and 2007 included underlying disease severity and delayed or forgone care in young adulthood.

CONCLUSIONS

We found significant deterioration in insurance coverage, usual source of care and receiving timely health care as ASHCN aged into adulthood, and that this was associated with decline in health status. Our findings suggest that further population-based analyses of health outcomes are needed to plan for interventions to assist this vulnerable population.

Transcomplementation by a truncation mutant of cystic fibrosis transmembrane conductance regulator (CFTR) enhances ΔF508 processing through a biomolecular interaction

We previously showed that a truncation mutant of CFTR missing the first four transmembrane segments of TMD1, Δ264 CFTR, binds to key elements in the ER quality control mechanism to increase the amounts of the mature C band of both wt and ΔF508 CFTR through transcomplementation. Here, we created a new construct, Δ27-264 CFTR. Even though Δ27-264 CFTR is rapidly degraded in the proteasome, steady state protein can be detected by Western blot. Δ27-264 CFTR can also increase the amounts of the mature C band of both wt and ΔF508 CFTR through transcomplementation. Electrophysiology experiments show that Δ27-264 CFTR can restore chloride channel currents. Further experiments with the conduction mutant S341A show conclusively that currents are indeed generated by rescued channel function of ΔF508 CFTR. Immunoprecipitation studies show that Δ27-264 binds to ΔF508-CFTR, suggesting a bimolecular interaction. Thus the adeno-associated viral vector, rAAV-Δ27-264 CFTR, is a highly promising CF gene therapy vector, because it increases the amount of mature band C protein both from wt and ΔF508 CFTR, and rescues channel activity of ΔF508 CFTR.

Better nutritional status in early childhood is associated with improved clinical outcomes and survival in patients with cystic fibrosis

OBJECTIVES

To evaluate the relationship between nutritional status early in life and the timing and velocity of height growth, lung function, complications of cystic fibrosis, and survival.

STUDY DESIGN

Prospective, observational study using data from the Cystic Fibrosis Foundation Registry (US) for patients born between 1989 and 1992 (n = 3142).

RESULTS

Weight-for-age percentile (WAP) at 4 years of age was positively associated with height-for-age percentiles throughout childhood. Age 4 years WAP >10% was associated with better lung function from 6-18 years of age. In boys and girls with current WAP >50%, peak pubertal height velocities approximated but remained lower than that of the healthy reference population. By age 18 years, patients with an age 4 years WAP >50% suffered fewer acute pulmonary exacerbations, spent fewer days in the hospital, and had lower rates of impaired glucose tolerance or diabetes. Patients attaining higher age 4 years WAP and height-for-age percentiles had a survival advantage throughout childhood.

CONCLUSION

For the population studied, greater weight at age 4 years is associated with greater height, better pulmonary function, fewer complications of cystic fibrosis, and better survival through age 18 years. Furthermore, greater weight-for-age in the peripubertal period is associated on average with improved tempo and timing of pubertal height growth.

Evaluation of the intestinal current measurement method as a diagnostic test for cystic fibrosis

BACKGROUND

The sweat test and nasal potential difference measurement are now established tools in the diagnostic work up of cystic fibrosis (CF). Intestinal current measurement (ICM) is under consideration as an aid in the diagnosis of CF especially in young children. The aim of this study is to evaluate the diagnostic reliability of ICM.

METHODS

Rectal biopsies were obtained from three groups: CF patients, controls, and patients who were suspected for CF. ICMs were performed by mounting the rectal biopsy in an Ussing chamber and sequentially adding secretagogues while recording current changes.

RESULTS

Twenty-one CF patients (aged 3.0 ± 3.8 years) and 16 controls (aged 15.6 ± 15.1 years) were examined and have remarkably different results (presented as µA/cm(2) ): carbachol 16.3 ± 6.9, histamine 13.2 ± 8.9, and cAMP/forskolin 4.8 ± 4.0 for control group and carbachol -1.5 ± 5.3 (P < 0.0001), histamine -1.5 ± 3.1 (P < 0.0001), and cAMP/forskolin 0.36 ± 0.67 (P < 0.0001) for the CF group. Our suggested reference values are: +5.40, +3.52, +2.19 for carbachol, histamine, and cAMP/forskolin, respectively. The combination parameter (the arithmetic sum of carbachol, histamine, and cAMP/forskolin) of +7.19 differentiates normal from abnormal (ROC curve analysis, area under the curve = 1.00, both sensitivity and specificity are 100%). This statistical model was applied to 71 patients suspected for CF and revealed that 66 patients had normal ICM results (combination >7.19) and five patients had abnormal ICM results (combination <7.19).

CONCLUSION

We have shown that ICM tests may be useful to differentiate between patients suspected to have CF. These results require confirmation so that ICM may be included in diagnostic algorithms.

Cost of cystic fibrosis: analysis of treatment costs in a specialized center in northern Italy

INTRODUCTION

Advances in cystic fibrosis (CF) therapy have resulted in improved survival and increasing treatment burden and costs. The economic impact of current treatment strategies for CF is poorly defined.

METHODS

The authors prospectively assessed direct medical costs (including hospitalizations, outpatient interventions, drugs, devices, dietetic products) in 165 consecutive CF patients (aged 5-39 years) seen between March and July 2009.

RESULTS

The mean annual cost/patient increased with age and lung disease severity from yy4,164 in children aged ≤5 years to yy30,123 in patients aged >5 years with severe lung disease (forced expiratory volume in 1 second [FEV1] <40% of predicted). The increase in costs involved all items, with a progressive increase in cost attributed to hospitalizations.

CONCLUSION

Treatment of CF is associated with relevant cost for the Italian National Healthcare Service. Costs of illness tend to increase progressively with age, suggesting that increasing economic resources should be allocated to the treatment of CF, given the increasing number of patients surviving into adulthood.

Th17/Treg imbalance in murine cystic fibrosis is linked to indoleamine 2,3-dioxygenase deficiency but corrected by kynurenines

RATIONALE

Mutations in the cystic fibrosis (CF) transmembrane conductance regulator affect the innate epithelial immune function of the lung, resulting in exaggerated and ineffective airway inflammation that fails to eradicate pathogenic fungi. The appreciation of whether such fungi are primarily responsible for or a consequence of ineffective airway inflammation is important for future therapeutics development.

OBJECTIVES

To characterize the impact of the tryptophan/kynurenine pathway on pathogenic airway inflammation preventing effective fungal clearance in CF.

METHODS

We studied the expression of indoleamine 2,3-dioxygenase (IDO), the first enzyme in the kynurenine pathway of tryptophan degradation, in human and murine CF, the impact of IDO on lung inflammation and immunity in murine CF, and the potential role of tryptophan catabolism in pathogenesis and therapy of fungus-associated lung inflammation.

MEASUREMENTS AND MAIN RESULTS

IDO was defective in murine and human CF. Genetic and transcriptional regulatory mechanisms contributed to dysfunctional IDO activity that, in turn, correlated with imbalanced Th17/Treg-cell responses to Aspergillus fumigatus in murine CF. Treatments enhancing IDO function or preventing pathogenic Th17-cell activation restored protective immunity to the fungus and improved lung inflammation in murine CF.

CONCLUSIONS

This study provides a link between tryptophan catabolism and lung immune homeostasis in murine CF, representing a proof-of-concept that targeting pathogenic inflammation via IDO-mimetic drugs may benefit patients with CF.

A Th17- and Th2-skewed cytokine profile in cystic fibrosis lungs represents a potential risk factor for Pseudomonas aeruginosa infection

RATIONALE

Cystic fibrosis (CF) is characterized by progressive pulmonary inflammation that is infection-triggered. Pseudomonas aeruginosa represents a risk factor for deterioration of lung function and reduced life expectancy.

OBJECTIVES

To assess T-cell cytokine/chemokine production in clinically stable children with CF and evaluate the association between T-cell subtypes and susceptibility for infection with P. aeruginosa.

METHODS

T-cell cytokine/chemokine profiles were measured in bronchoalveolar lavage fluid (BALF) from children with CF (n = 57; 6.1 ± 5.9 yr) and non-CF control subjects (n = 18; 5.9 ± 4.3 yr). Memory responses to Aspergillus fumigatus and P. aeruginosa were monitored. High-resolution computed tomography-based Helbich score was assessed. In a prospective observational trial the association between BALF cytokine/chemokine profiles and subsequent infection with P. aeruginosa was studied.

MEASUREMENTS AND MAIN RESULTS

Th1- (INF-γ), Th2- (IL-5, IL-13), Th17- (IL-17A), and Th17-related cytokines (IL-1β, IL-6) were significantly up-regulated in airways of patients with CF. IL-17A, IL-13, and IL-5 were significantly higher in BALF of symptomatic as compared with clinically asymptomatic patients with CF. IL-17A and IL-5 correlated with the percentage of neutrophils in BALF (r = 0.41, P < 0.05 and r = 0.46, P < 0.05, respectively). Th17- (IL-17A, IL-6, IL-1β, IL-8) and Th2-associated cytokines and chemokines (IL-5, IL-13, TARC/CCL17), but not IFN-γ levels, significantly correlated with high-resolution computed tomography changes (Helbich score; P < 0.05). P. aeruginosa- and A. fumigatus-specific T cells from patients with CF displayed significantly higher IL-5 and IL-17A mRNA expression. IL-17A and TARC/CCL17 were significantly augmented in patients that developed P. aeruginosa infection within 24 months.

CONCLUSIONS

We propose a role for Th17 and Th2 T cells in chronic inflammation in lungs of patients with CF. High concentrations of these cytokines/chemokines in CF airways precede infection with P. aeruginosa.

Reference percentiles for FEV(1) and BMI in European children and adults with cystic fibrosis

Background

The clinical course of Cystic Fibrosis (CF) is usually measured using the percent predicted FEV₁ and BMI Z-score referenced against a healthy population, since achieving normality is the ultimate goal of CF care. Referencing against age and sex matched CF peers may provide valuable information for patients and for comparison between CF centers or populations. Here, we used a large database of European CF patients to compute CF specific reference equations for FEV₁ and BMI, derived CF-specific percentile charts and compared these European data to their nearest international equivalents.

Methods

34859 FEV₁ and 40947 BMI observations were used to compute European CF specific percentiles. Quantile regression was applied to raw measurements as a function of sex, age and height. Results were compared with the North American equivalent for FEV₁ and with the WHO 2007 normative values for BMI.

Results

FEV₁ and BMI percentiles illustrated the large variability between CF patients receiving the best current care. The European CF specific percentiles for FEV₁ were significantly different from those in the USA from an earlier era, with higher lung function in Europe. The CF specific percentiles for BMI declined relative to the WHO standard in older children. Lung function and BMI were similar in the two largest contributing European Countries (France and Germany).

Conclusion

The CF specific percentile approach applied to FEV₁ and BMI allows referencing patients with respect to their peers. These data allow peer to peer and population comparisons in CF patients.

Matrine modulates HSC70 levels and rescues ΔF508-CFTR

Cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-dependent Cl(-) channel located in the plasma membrane, and its malfunction results in cystic fibrosis (CF), the most common lethal genetic disease in Caucasians. Most CF patients carry the deletion of Phe508 (ΔF508 mutation); this mutation prevents the delivery of the CFTR to its correct cellular location, the apical (lumen-facing) membrane of epithelial cells. Molecular chaperones play a central role in determining the fate of ΔF508-CFTR. In this report, we show that the Matrine, a quinolizidine alkaloid, downregulates the expression of the molecular chaperone HSC70 and increases the protein levels of ΔF508-CFTR in human alveolar basal epithelial cells (A549 cell line), stably transfected with a ΔF508-CFTR-expressing construct. Moreover, Matrine induced ΔF508-CFTR release from endoplasmic reticulum to cell cytosol and its localization on the cell membrane. Interestingly, downregulation of HSC70 resulted in increased levels of ΔF508-CFTR complexes with the co-chaperone BAG3 that in addition appeared to co-localize with the mutated protein on the cell surface. These results shed new light on ΔF508-CFTR interactions with proteins of the chaperones/co-chaperones system and could be useful in strategies for future medical treatments for CF.

Metabolomic profiling of regulatory lipid mediators in sputum from adult cystic fibrosis patients

Retained respiratory tract (RT) secretions, infection, and exuberant inflammatory responses are core abnormalities in cystic fibrosis (CF) lung disease. Factors contributing to the destructive CF airway inflammatory processes remain incompletely characterized. The pro-oxidative inflammatory CF RT milieu is known to contain enzymatically and nonenzymatically produced regulatory lipid mediators, a panel of structurally defined oxidized metabolites of polyunsaturated fatty acids known to play a role in pathology related to inflammation. Using an extraction protocol that maximizes recoveries of sputum-spiked deuterated standards, coupled with an LC/MS/MS detection system, this study presents a metabolomic method to assess a broad spectrum of regulatory lipid mediators in freshly obtained sputum from CF patients. A broad range of both proinflammatory and anti-inflammatory lipid mediators was detected, including PGE2, PGD2, TXB2, LTB4, 6-trans-LTB4, 20-OH-LTB4, 20-COOH-LTB4, 20-HETE, 15-HETE, 11-HETE, 12-HETE, 8-HETE, 9-HETE, 5-HETE, EpETrEs, diols, resolvin E1, 15-deoxy-PGJ2, and LXA4. The vast majority of these oxylipins have not been reported previously in CF RT secretions. Whereas direct associations of individual proinflammatory lipid mediators with compromised lung function (FEV-1) were observed, the relationships were not robust. However, multiple statistical analyses revealed that the regulatory lipid mediators profile taken in aggregate proved to have a stronger association with lung function in relatively stable outpatient adult CF patients. Our data reveal a relative paucity of the anti-inflammatory lipid mediator lipoxin A4 in CF sputum. Patients displaying detectable levels of the anti-inflammatory lipid mediator resolvin E1 demonstrated a better lung function compared to those patients with undetectable levels. Our data suggest that comprehensive metabolomic profiling of regulatory lipid mediators in CF sputum should contribute to a better understanding of the molecular mechanisms underlying CF RT inflammatory pathobiology. Further studies are required to determine the extent to which nutritional or pharmacological interventions alter the regulatory lipid mediators profile of the CF RT and the impact of potential modulations of RT regulatory lipid mediators on the clinical progression of CF lung disease.

Personalized medicine in cystic fibrosis: dawning of a new era

Life expectancy in cystic fibrosis (CF) has improved substantially over the last 75 years, with a median predicted survival now approaching 40 years. This improvement has resulted largely from therapies treating end-organ manifestations. In an effort to develop drugs that would target the underlying defects in the CF transmembrane conductance regulator (CFTR), the Cystic Fibrosis Foundation embarked on a bold initiative in which it established collaborations with biopharmaceutical companies to support early-stage efforts to discover new medicines for CF. This has led to the development and clinical trial testing of several novel drugs targeting specific CFTR mutations. One drug, ivacaftor, was recently approved by the US Food and Drug Administration for the approximately 4% of patients with CF who have the G551D gating mutation. Drugs targeting F508del CFTR and premature termination codons, which would be applicable to 90% of patients with CF, are undergoing clinical trials. The impact of such drugs on CFTR biomarkers, such as sweat chloride and nasal potential difference, suggests that they may reset the clinical trajectory of CF, but their effect on long-term outcomes will remain unknown for many years. Nevertheless, development of CFTR-targeted drugs represents an important milestone in CF, perhaps revolutionizing the care of these patients in a fundamental way.

In vitro and in vivo properties of a fully human IgG1 monoclonal antibody that combats multidrug resistant Pseudomonas aeruginosa

The development of an anti-bacterial drug in the form of a monoclonal antibody (mAb) targeting an exposed virulence factor, represents an innovative therapeutic strategy. Consequently, a fully human IgG1 mAb (LST-007) targeting Pseudomonas aeruginosa (PA) flagellin type b was recombinantly expressed and characterized in vitro and in an infection model driven by a multidrug resistant (MDR) PA strain. LST-007 demonstrated a highly specific binding towards whole PA bacteria harboring flagellin type b and its recombinant counterpart, with a K(D) of 7.4x10(-10) M. In bioactivity assays, LST-007 or titers of Cmax sera derived from pharmacokinetic studies, markedly attenuated PA motility in an equipotent manner. In vivo, parenteral LST-007 (20 mg/kg) given as a single or double-dosing paradigm post-infection, afforded survival (up to 75% at Day 7) in a lethal model of pneumonia driven by the intratracheal (i.t.) instillation of an LD(80) of the MDR PA isolate. This protective effect was markedly superior to that of imipenem (30% survival at Day 7) and totally devoid with an irrelevant, human isotype mAb. These data lay credence that LST-007 may be a valuable adjunct to the limited list of anti-bacterials that can tackle MDR PA strains, thereby warranting its continued development for eventual clinical evaluation.

Maintenance of nutritional status in patients with cystic fibrosis: new and emerging therapies

Poor clinical outcomes in cystic fibrosis are often associated with undernutrition. Normal growth and development should be achieved in cystic fibrosis, and nutritional counseling is paramount at all ages. Prevention and early detection of growth failure is the key to successful nutritional intervention. The advance in nutritional management is certainly one factor that has contributed to the improved survival in recent decades. This review outlines the major nutritional parameters in the management of the patient with cystic fibrosis, including recent advances in pancreatic enzyme replacement therapy and fat-soluble vitamin therapy. There are sections on complicated clinical situations which directly affect nutrition, for example, before and after lung transplantation, cystic fibrosis-related diabetes, and bone health.

Neurology of inherited glycosylation disorders

Congenital disorders of glycosylation comprise most of the nearly 70 genetic disorders known to be caused by impaired synthesis of glycoconjugates. The effects are expressed in most organ systems, and most involve the nervous system. Typical manifestations include structural abnormalities (eg, rapidly progressive cerebellar atrophy), myopathies (including congenital muscular dystrophies and limb-girdle dystrophies), strokes and stroke-like episodes, epileptic seizures, developmental delay, and demyelinating neuropathy. Patients can also have neurological symptoms associated with coagulopathies, immune dysfunction with or without infections, and cardiac, renal, or hepatic failure, which are common features of glycosylation disorders. The diagnosis of congenital disorder of glycosylation should be considered for any patient with multisystem disease and in those with more specific phenotypic features. Measurement of concentrations of selected glycoconjugates can be used to screen for many of these disorders, and molecular diagnosis is becoming more widely available in clinical practice. Disease-modifying treatments are available for only a few disorders, but all affected individuals benefit from early diagnosis and aggressive management.

Improvements in cystic fibrosis lung disease and airway inflammation associated with etanercept therapy for rheumatoid arthritis: a case report

Cystic fibrosis (CF) lung pathology is characterized by excessive neutrophilic inflammation and high tumor necrosis factor-alpha (TNF-α) levels. A cornerstone of CF management is reduction of the inflammatory burden in the lung. We present the case of a 19-year-old CF patient who demonstrated significant clinical improvement in her lung disease associated with a reduction in sputum percent neutrophils, following commencement of etanercept (TNF-α antagonist) for rheumatoid arthritis. She has not had any infectious complications or other significant adverse effects during 2 years of treatment. It may be time to reconsider TNF-α antagonists as potential anti-inflammatory agents for CF lung disease.