The implications and management of cystic fibrosis screen positive, inconclusive diagnosis patients.

Newborn screening and extensive genetic analysis has led to the recognition of a cohort of infants with an equivocal diagnosis of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) disease. This paper reviews the comprehensive approach required for diagnosis of Cystic Fibrosis Screen Positive, Inconclusive Diagnosis (CFSPID) and uses an illustrative case with p.Asp1152His (D1152H) mutation to examine the varying clinical phenotype seen amongst CFSPID patients. Whilst infants are well at diagnosis, uncertainties about cystic fibrosis (CF) disease progression indicate the importance of monitoring and early specialist involvement. However, over-medicalisation can cause significant psychosocial impact on patients' and families. The complexities underlying the surveillance and long-term management of patients with CFSPID are explored.

Levelling the playing field through the London Network of the UK clinical trials accelerator platform.

Cystic fibrosis (CF) is a multisystem, genetic disease with a significantly reduced life expectancy. Despite substantial progress in therapies in the last 10-15 years, there is still no cure. There are dozens of drugs in the development pipeline and multiple clinical trials are being conducted across the globe. The UK Cystic Fibrosis Trust's (CFT) Clinical Trials Accelerator Platform (CTAP) is a national initiative bringing together 25 UK based CF centres to support the CF community in accessing and participating in CF clinical trials. CTAP enables more CF centres to run a broader portfolio of trials and increases the range of CF studies available for UK patients. There are four large specialist CF centres based in London, all within a small geographical region as well as two smaller centres which deliver CF care. At the launch of CTAP, these centres formed a sub-network in a consortium-style collaboration. The purpose of the network was to ensure equity of access to trials for patients across the UK's capital, and to share experience and knowledge. Four years into the programme we have reviewed our practices through working group meetings and an online survey. We sought to identify strengths and areas for improvement. We share our findings here, as we believe they are relevant to others delivering research in regions outside of London and in other chronic diseases.

Gastroesophageal Reflux Disease and Need for Antireflux Surgery in Children with Cystic Fibrosis: A Systematic Review on Incidence, Surgical Complications, and Postoperative Outcomes.

INTRODUCTION: Gastroesophageal reflux disease (GERD) is associated with accelerated decline in lung health in children with cystic fibrosis (CF). Thus, antireflux surgery (ARS) is offered to a selected CF cohort with refractory GERD, but outcomes remain poorly investigated. This study aimed to determine the incidence of GERD in children with CF and to evaluate complications and outcomes of ARS. MATERIALS AND METHODS: A systematic literature-based search was conducted using various online databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The number of GERD cases in pediatric CF cohorts who underwent diagnostic investigation(s) was recorded. Data on postoperative complications and outcomes (including symptoms, lung function, and nutritional status) following ARS were analyzed. RESULTS: Ten articles (n = 289 patients) met the defined inclusion criteria (51% male; age range, 0.5 month-36 years). The overall incidence of GERD was 46% (range, 19-81%), derived from seven studies (n = 212 patients). Four publications (n = 82 patients) reported on ARS due to uncontrolled GERD. All ARSs were Nissen fundoplication (majority with gastrostomy placement). Major postoperative complications occurred in 15 (18%) patients, two required redo-ARS. Median follow-up time was 2 years (range, 3 months-6 years); 59% showed symptom improvement, and pulmonary exacerbations and decline in lung function were reduced. Nutritional status mainly improved in milder CF cases. There were no deaths related to ARS. CONCLUSION: Approximately half of pediatric CF patients have GERD. Published data for children with CF are limited and heterogeneous in terms of GERD diagnosis and outcomes following ARS. However, ARS has shown to slow the deterioration of lung function in CF.

Minimal change in structural, functional and inflammatory markers of lung disease in newborn screened infants with cystic fibrosis at one year.

BACKGROUND: With the widespread introduction of newborn screening for cystic fibrosis (CF), there has been considerable emphasis on the need to develop objective markers of lung health that can be used during infancy. We hypothesised that in a newborn screened (NBS) UK cohort, evidence of airway inflammation and infection at one year would be associated with adverse structural and functional outcomes at the same age. METHODS: Infants underwent lung function testing, chest CT scan and bronchoscopy with bronchoalveolar lavage (BAL) at 1 year of age when clinically well. Microbiology cultures were also available from routine cough swabs. RESULTS: 65 infants had lung function, CT and BAL. Mean (SD) lung clearance index and forced expiratory volume in 0.5 s z-scores were 0.9(1.2) and -0.6(1.1) respectively; median Brody II CF-CT air trapping score on chest CT =0 (interquartile range 0-1, maximum possible score 27). Infants isolating any significant pathogen by 1 yr of age had higher LCI z-score (mean difference 0.9; 95%CI:0.4-1.4; p = 0.001) and a trend towards higher air trapping scores on CT (p = 0.06). BAL neutrophil elastase was detectable in 23% (10/43) infants in whom BAL supernatant was available. This did not relate to air trapping score on CT. CONCLUSIONS: In this UK NBS cohort at one year of age, lung and airway damage is much milder and associations between inflammation, abnormal physiology and structural changes were at best weak, contrary to our hypothesis and previously published reports. Continued follow-up will clarify longer term implications of these very mild structural, functional and inflammatory changes.

[Real-world effectiveness of ivacaftor in children with cystic fibrosis and the G551D mutation]. / Efectividad de ivacaftor en vida real en niños con fibrosis quística y mutación G551D.

INTRODUCTION: Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator that has been shown to improve the nutritional status and lung function of cystic fibrosis patients with the G551D mutation in clinical trials. The objective of this study was to describe the real-world progress of children receiving ivacaftor. METHODS: We describe the real-world progress of four children with cystic fibrosis and the F508del/G551D genotype comparing data during ivacaftor treatment with baseline and with the year before commencing treatment. RESULTS: Our sample comprised 4 children aged between 6 and 14 years and including one with a recent diagnosis of CF and other with persistent Mycobacterium abscessus (M. abscessus) and recurrent allergic bronchopulmonary aspergillosis. The baseline FEV1 was 58.5% to 81.8% of the predicted value, and ivacaftor was taken for a mean 24 months (range, 12-30 months). All patients experienced a significant and sustained improvement in lung function. Compared to baseline, the weight z-score improved by 1.53 points, and the BMI z-score by 1.6 points. Compared to the year before starting ivacaftor, the frequency of Pseudomonas aeruginosa (P. aeruginosa) isolates decreased (-0.4/patient/year), as did the number of respiratory exacerbations (-1.8/patient/year). The weight-adjusted dose of lipase per kilogram decreased progressively in all patients. In 1 patient, a previously persistent M. abscessus infection and recurrent allergic bronchopulmonary aspergillosis resolved during treatment. CONCLUSIONS: Children with cystic fibrosis and the F508del/G551D genotype receiving treatment with ivacaftor experienced a real-world improvement in lung function, nutritional status, respiratory exacerbations, isolation of P. aeruginosa, and dose of pancreatic enzymes.

Quality Improvement Project to Evaluate Discharge Prescriptions in Children With Cystic Fibrosis.

Cystic Fibrosis (CF) requires multiple pharmaceutical treatments, elevating the risk of medication errors (ME), which may compromise patient safety. This study aimed to improve the quality of discharge prescriptions (DPs) using indicators following admissions for IV antibiotics in pediatric CF patients. METHODS: This project involved a longitudinal observational retrospective descriptive study followed by a longitudinal quasi-experimental prospective phase between January 2013 and December 2016 in CF patients admitted to a London Children's Hospital. The CF pharmacist reviewed DPs. Six rights of medication administration were defined (6R): dose, drug, frequency, duration of treatment, pharmaceutical form, and route of administration. We classified ME according to 6R, including subtype of error: committed/omitted. We calculated quality indicators by dividing the number of each correct parameter defined by 6R by number of DPs. Retrospective results were used prospectively to describe and implement improvement strategies and safety actions. RESULTS: The retrospective study phase included 42 CF children (100 hospital admissions and 1,343 drugs). The prospective phase included thirty-five children (55 admissions and 822 drugs). The total number of ME identified was 148 (78 committed; 70 omitted) in retrospective phase and 135 (19 committed; 116 omitted) in prospective phase. Quality indicators for drug and dose showed significant improvement after implementing safety strategies. The global quality indicator increased from 22% (retrospective) to 41.82% (prospective), but we did not achieve the previously defined quality standard value (50%). CONCLUSIONS: A retrospective review of DP by a CF Pharmacist identified failures in DP quality. Implementing improvement strategies improved prescribing. Integrating pharmacist within multidisciplinary team improves DP reducing errors.

Bright Surface-Enhanced Raman Scattering with Fluorescence Quenching from Silica Encapsulated J-Aggregate Coated Gold Nanoparticles.

Plexitonic nanoparticles offer variable optical properties through tunable excitations, in addition to electric field enhancements that far exceed molecular resonators. This study demonstrates a way to design an ultrabright surface-enhanced Raman spectroscopy (SERS) signal while simultaneously quenching the fluorescence background through silica encapsulation of the semiconductor-metal composite nanoparticles. Using a multistep approach, a J-aggregate-forming organic dye is assembled on the surface of gold nanoparticles using a cationic linker. Excitonic resonance of the J-aggregate-metal system shows an enhanced SERS signal at an appropriate excitation wavelength. Further encapsulation of the decorated particles in silica shows a significant reduction in the fluorescence signal of the Raman spectra (5× reduction) and an increase in Raman scattering (7× enhancement) when compared to phospholipid encapsulation. This reduction in fluorescence is important for maximizing the useful SERS enhancement from the particle, which shows a signal increase on the order of 104 times greater than J-aggregated dye in solution and 24 times greater than Oxonica S421 SERS tag. The silica layer also serves to promote colloidal stability. The combination of reduced fluorescence background, enhanced SERS intensity, and temporal stability makes these particles highly distinguishable with potential to enable high-throughput applications such as SERS flow cytometry.

The use of whole-exome sequencing to disentangle complex phenotypes.

The success of whole-exome sequencing to identify mutations causing single-gene disorders has been well documented. In contrast whole-exome sequencing has so far had limited success in the identification of variants causing more complex phenotypes that seem unlikely to be due to the disruption of a single gene. We describe a family where two male offspring of healthy first cousin parents present a complex phenotype consisting of peripheral neuropathy and bronchiectasis that has not been described previously in the literature. Due to the fact that both children had the same problems in the context of parental consanguinity we hypothesised illness resulted from either X-linked or autosomal recessive inheritance. Through the use of whole-exome sequencing we were able to simplify this complex phenotype and identified a causative mutation (p.R1070*) in the gene periaxin (PRX), a gene previously shown to cause peripheral neuropathy (Dejerine-Sottas syndrome) when this mutation is present. For the bronchiectasis phenotype we were unable to identify a causal single mutation or compound heterozygote, reflecting the heterogeneous nature of this phenotype. In conclusion, in this study we show that whole-exome sequencing has the power to disentangle complex phenotypes through the identification of causative genetic mutations for distinct clinical disorders that were previously masked.

Heliox therapy in bronchiolitis: phase III multicenter double-blind randomized controlled trial.

BACKGROUND AND OBJECTIVE: Supportive care remains the mainstay of therapy in bronchiolitis. Earlier studies suggest that helium-oxygen therapy may be beneficial, but evidence is limited. We aimed to compare efficacy of 2 treatment gases, Heliox and Airox (21% oxygen + 79% helium or nitrogen, respectively), on length of hospital treatment for bronchiolitis. METHODS: This was a multicenter randomized blinded controlled trial of 319 bronchiolitic infant subjects randomly assigned to either gas; 281 subjects completed the study (140 Heliox, 141 Airox), whose data was analyzed. Treatment was delivered via facemask (nasal cannula, if the facemask intolerant) ± continuous positive airway pressure (CPAP). Severe bronchiolitics received CPAP from the start. Primary end point was length of treatment (LoT) required to alleviate hypoxia and respiratory distress. Secondary end-points were proportion of subjects needing CPAP; CPAP (LoT); and change in respiratory distress score. RESULTS: Analysis by intention to treat (all subjects); median LoT (inter-quartile range, days): Heliox 1.90 (1.08-3.17), Airox 1.87 (1.11-3.34), P = .41. Facemask tolerant subgroup: Heliox 1.46 (0.85-1.95), Airox 2.01 (0.93-2.86), P = .03. Nasal cannula subgroup: Heliox 2.51 (1.21-4.32), Airox 2.81 (1.45-4.78), P = .53. Subgroup started on CPAP: Heliox 1.55 (1.38-2.01), Airox 2.26 (1.84-2.73), P = .02. Proportion of subjects needing CPAP: Heliox 17%, Airox 19%, O.R. 0.87 (0.47-1.60), P = .76. Heliox reduced respiratory distress score after 8 hours (mixed models estimate, -0.1298; P < .001). The effect was greater for facemask compared with nasal cannula (mixed models estimate, 0.093; P = .04). CONCLUSIONS: Heliox therapy does not reduce LoT unless given via a tight-fitting facemask or CPAP. Nasal cannula heliox therapy is ineffective.

A disease model for wheezing disorders in preschool children based on clinicians' perceptions.

BACKGROUND: Wheezing disorders in childhood vary widely in clinical presentation and disease course. During the last years, several ways to classify wheezing children into different disease phenotypes have been proposed and are increasingly used for clinical guidance, but validation of these hypothetical entities is difficult. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study was to develop a testable disease model which reflects the full spectrum of wheezing illness in preschool children. We performed a qualitative study among a panel of 7 experienced clinicians from 4 European countries working in primary, secondary and tertiary paediatric care. In a series of questionnaire surveys and structured discussions, we found a general consensus that preschool wheezing disorders consist of several phenotypes, with a great heterogeneity of specific disease concepts between clinicians. Initially, 24 disease entities were described among the 7 physicians. In structured discussions, these could be narrowed down to three entities which were linked to proposed mechanisms: a) allergic wheeze, b) non-allergic wheeze due to structural airway narrowing and c) non-allergic wheeze due to increased immune response to viral infections. This disease model will serve to create an artificial dataset that allows the validation of data-driven multidimensional methods, such as cluster analysis, which have been proposed for identification of wheezing phenotypes in children. CONCLUSIONS/SIGNIFICANCE: While there appears to be wide agreement among clinicians that wheezing disorders consist of several diseases, there is less agreement regarding their number and nature. A great diversity of disease concepts exist but a unified phenotype classification reflecting underlying disease mechanisms is lacking. We propose a disease model which may help guide future research so that proposed mechanisms are measured at the right time and their role in disease heterogeneity can be studied.

Randomized controlled trial of fluticasone in preschool children with intermittent wheeze.

Preschool children with intermittent wheeze are often prescribed inhaled corticosteroids, although there is no proven benefit. Measurement of airway resistance by the interrupter technique can be used to objectively assess response to treatment. If lung function improves, treatment may be justified. Children with intermittent wheeze aged 2 to