Lung Clearance Index to Track Acute Respiratory Events in School-Age Children with Cystic Fibrosis.

Rationale: The lung clearance index (LCI) is responsive to acute respiratory events in preschool children with cystic fibrosis (CF), but its utility to identify and manage these events in school-age children with CF is not well defined.Objectives: To describe changes in LCI with acute respiratory events in school-age children with CF.Methods: In a multisite prospective observational study, the LCI and FEV1 were measured quarterly and during acute respiratory events. Linear regression was used to compare relative changes in LCI and FEV1% predicted at acute respiratory events. Logistic regression was used to compare the odds of a significant worsening in LCI and FEV1% predicted at acute respiratory events. Generalized estimating equation models were used to account for repeated events in the same subject.Measurements and Main Results: A total of 98 children with CF were followed for 2 years. There were 265 acute respiratory events. Relative to a stable baseline measure, LCI (+8.9%; 95% confidence interval, 6.5 to 11.3) and FEV1% predicted (-6.6%; 95% confidence interval, -8.3 to -5.0) worsened with acute respiratory events. A greater proportion of events had a worsening in LCI compared with a decline in FEV1% predicted (41.7% vs. 30.0%; P = 0.012); 53.9% of events were associated with worsening in LCI or FEV1. Neither LCI nor FEV1 recovered to baseline values at the next follow-up visit.Conclusions: In school-age children with CF, the LCI is a sensitive measure to assess lung function worsening with acute respiratory events and incomplete recovery at follow-up. In combination, the LCI and FEV1 capture a higher proportion of events with functional impairment.

Determinants of lung disease progression measured by lung clearance index in children with cystic fibrosis.

The lung clearance index (LCI) measured by the multiple breath washout (MBW) test is sensitive to early lung disease in children with cystic fibrosis. While LCI worsens during the preschool years in cystic fibrosis, there is limited evidence to clarify whether this continues during the early school age years, and whether the trajectory of disease progression as measured by LCI is modifiable.A cohort of children (healthy and cystic fibrosis) previously studied for 12 months as preschoolers were followed during school age (5-10 years). LCI was measured every 3 months for a period of 24 months using the Exhalyzer D MBW nitrogen washout device. Linear mixed effects regression was used to model changes in LCI over time.A total of 582 MBW measurements in 48 healthy subjects and 845 measurements in 64 cystic fibrosis subjects were available. The majority of children with cystic fibrosis had elevated LCI at the first preschool and first school age visits (57.8% (37 out of 64)), whereas all but six had normal forced expiratory volume in 1 s (FEV1) values at the first school age visit. During school age years, the course of disease was stable (-0.02 units·year-1 (95% CI -0.14-0.10). LCI measured during preschool years, as well as the rate of LCI change during this time period, were important determinants of LCI and FEV1, at school age.Preschool LCI was a major determinant of school age LCI; these findings further support that the preschool years are critical for early intervention strategies.

Progression of Lung Disease in Preschool Patients with Cystic Fibrosis.

RATIONALE: Implementation of intervention strategies to prevent lung damage in early cystic fibrosis (CF) requires objective outcome measures that capture and track lung disease. OBJECTIVES: To define the utility of the Lung Clearance Index (LCI), measured by multiple breath washout, as a means to track disease progression in preschool children with CF. METHODS: Children with CF between the ages of 2.5 and 6 years with a confirmed diagnosis of CF and age-matched healthy control subjects were enrolled at three North American CF centers. Multiple breath washout tests were performed at baseline, 1, 3, 6, and 12 months to mimic time points chosen in clinical care and interventional trials; spirometry was also conducted. A generalized linear mixed-effects model was used to distinguish LCI changes associated with normal growth and development (i.e., healthy children) from the progression of CF lung disease. MEASUREMENTS AND MAIN RESULTS: Data were collected on 156 participants with 800 LCI measurements. Although both LCI and spirometry discriminated health from disease, only the LCI identified significant deterioration of lung function in CF over time. The LCI worsened during cough episodes and pulmonary exacerbations, whereas similar symptoms in healthy children were not associated with increased LCI values. CONCLUSIONS: LCI is a useful marker to track early disease progression and may serve as a tool to guide therapies in young patients with CF.

Facilitating access to biodiversity information: a survey of users' needs and practices.

Biodiversity information is essential for understanding and managing the environment. However, identifying and providing the forms and types of biodiversity information most needed for research and decision-making is a significant challenge. While research needs and data gaps within particular topics or regions have received substantial attention, other information aspects such as data formats, sources, metadata, and information tools have received little. Focusing on the US southeast, a region of global biodiversity importance, this paper assesses the biodiversity information needs of environmental researchers, managers, and decision makers. Survey results of biodiversity information users' information needs, information-seeking behaviors and preferred information source attributes support previous conclusions that useful biodiversity information must be easily and quickly accessible, available in forms that allow integration and visualization and appropriately matched to users' needs. Survey results concerning additional information aspects suggest successful participation in both the creation and provision of biodiversity information include an increased focus on information search and other tools for data management, discovery, and description.

Building a pediatric rare lung disease program: It takes a community of villages.

Pediatric rare lung disease programs are increasing in number due to an increase in recognition of the diseases, increased clinical and research interest in children's interstitial lung disease, and the expansion of the children's interstitial lung disease research network. Due to this increased interest newly graduated trainees in pediatric pulmonology and other physicians are often starting new programs, which can be daunting. We provide some guidance for new programs based on our experiences.

Esophageal pH monitoring with the BRAVO capsule: experience in a single tertiary medical center.

AIM: The aim of the present study was to report the global experience with placement, complication rate, and recording of esophageal pH using the BRAVO capsule at our institution. PATIENTS AND METHODS: We recorded the rate of any technical problems and complications during placement in all of the patients (ages 4-22 years) who received this device during a 2-year period. All of the patients undergoing esophagogastroduodenoscopy with the placement of BRAVO pH capsule were included in this analysis. We also examined the pH data recorded on days 1 and 2 for significant day-to-day variability during 2 days of pH monitoring. RESULTS: Two hundred eighty-nine BRAVO pH probes were placed from January 1, 2006 to December 31, 2008. At least 1 day of data was obtained in 278 patients (96.2%). Two days of data were obtained in 274 patients (94.8%). Of all of the reported complications, 1% occurred before deployment of the capsule, 4% occurred during deployment of the capsule, and 9% occurred after successful deployment of the capsule. One patient experienced a superficial esophageal tear that was associated with failure of the capsule to release from the delivery system. No patient requested removal of the capsule and all of the capsules detached within 14 days. In 9.12% of our patients, reflux index was normal on day 1 and abnormal on day 2. There was no statistically significant difference between reflux index recorded on day 1 versus day 2 (P = 0.686). CONCLUSIONS: The BRAVO pH capsule is easy to place, safe, and well tolerated by children. Performing a 48-hour study detected abnormal reflux in an additional 9% of our patients.

Exploring potential noninvasive biomarkers in eosinophilic esophagitis in children.

BACKGROUND AND AIMS: Eosinophilic esophagitis (EE) continues to present clinical challenges, including a need for noninvasive tools to manage the disease. To identify a marker able to assess disease status in lieu of repeated endoscopies, we examined 3 noninvasive biomarkers, serum interleukin (IL)-5, serum eosinophil-derived neurotoxin (EDN), and stool EDN, and examined possible correlations of these with disease phenotype and activity (symptoms and histology) in a longitudinal study of children with EE. SUBJECTS AND METHODS: Children with EE were studied for up to 24 weeks (12 weeks on 1 of 2 corticosteroid therapies and 12 weeks off therapy). Twenty children with normal esophagogastroduodenoscopies with biopsies were enrolled as controls. Serum IL-5, serum EDN, and stool EDN were measured at weeks 0, 4, 12, 18, and 24 in children with EE, and at baseline alone for controls. Primary and secondary statistical analyses (excluding and including outlier values of the biomarkers, respectively) were performed. RESULTS: Sixty subjects with EE (46 [75%] boys, mean age 7.5 ±â€Š4.4 years) and 20 normal controls (10 [50%] boys, mean age 6.7 ±â€Š4.1 years) were included. Significant changes in serum EDN (significant decrease from baseline to week 4, and then rebound from week 4 to week 12) occurred. Serum EDN levels were stable after week 12. Serum IL-5 and stool EDN levels in subjects with EE were not statistically different from those of the control subjects when each time point for the cases was compared with the controls' 1-time measurement. CONCLUSIONS: Serum EDN levels were significantly higher in subjects with EE than in controls, and the results suggest a possible role, after additional future studies, for serum EDN in establishing EE diagnosis, assessing response to therapy, and/or monitoring for relapse or quiescence.

Potential Impact of COVID-19 Disruptions on the Next Generation of Vision Scientists.

Importance: Emerging vision scientists who have yet to be awarded their first independent funding may have their research careers disproportionately affected by early COVID-19-related disruptions. In September 2020, the Alliance for Eye and Vision Research convened a panel of 22 such scientists (nominated by their academic institutions) to communicate to the US Congress about the importance of vision research. As part of the effort, interviews were conducted with scientists about the effect of the pandemic on their research. Observations: Qualitative areas of adverse consequences from the early months of COVID-19 disruptions included striking interruptions of patient-based research, limits on other types of clinical research, loss of research time for scientists with young children (especially women), challenges with animal colonies and cell cultures, impediments to research collaborations, and loss of training time. Conclusions and Relevance: The early months during the COVID-19 pandemic increased career stress on many early-stage investigators in the vision field and delayed (and may potentially derail) their ability to attract their first independent research funding grant. As a result, federal and private granting agencies may need to take these factors into account to retain talented, early-stage vision researchers.

Utility of fecal lactoferrin in identifying Crohn disease activity in children.

OBJECTIVES: Fecal lactoferrin (FL) is a noninvasive biomarker that is elevated in Crohn disease (CD) compared to irritable bowel syndrome. The purpose of this study was to evaluate FL in identifying children with active versus inactive CD. PATIENTS AND METHODS: Fresh stool samples were collected from children with CD scheduled for endoscopy or a clinic visit, and from new outpatients who were scheduled for colonoscopy. FL was determined using a polyclonal antibody-based enzyme-linked immunosorbent assay. Physical global assessment, endoscopic findings, erythrocyte sedimentation rate (ESR), and the Pediatric CD Activity Index (PCDAI) were recorded for patients with CD. The PCDAI scores symptoms, laboratory parameters, physical examination, and extraintestinal manifestations. A score of ≤10 is inactive disease, 11 to 30 is mild active, and ≤31 is moderate to severe active. RESULTS: Of 101 study patients (4- to 20-year-old, 66 boys), 31 had active CD, 23 had inactive CD, and 37 had noninflammatory bowel disease (non-IBD) conditions. Four patients with ulcerative colitis and 6 patients with polyposis were excluded from analysis. FL was significantly elevated in CD versus non-IBD (P < 0.001) and in active versus inactive CD (P < 0.001). The PCDAI and ESR were higher in active CD than in inactive CD (both P < 0.001). Using an FL cutoff of 7.25 µg/g, FL has 100% sensitivity and 100% negative predictive value in detecting active CD. Using an FL cutoff level of 60 µg/g, FL had 84% sensitivity, 74% specificity, 81% positive predictive value, and 77% negative predictive value for detecting active CD. CONCLUSIONS: FL is a promising biomarker of active CD and may be more practical to use when it is not feasible to obtain all of the necessary clinical information for the PCDAI.

What makes an effective grants peer reviewer? An exploratory study of the necessary skills.

This exploratory mixed methods study describes skills required to be an effective peer reviewer as a member of review panels conducted for federal agencies that fund research, and examines how reviewer experience and the use of technology within such panels impacts reviewer skill development. Two specific review panel formats are considered: in-person face-to-face and virtual video conference. Data were collected through interviews with seven program officers and five expert peer review panelists, and surveys from 51 respondents. Results include the skills reviewers' consider necessary for effective review panel participation, their assessment of the relative importance of these skills, how they are learned, and how review format affects skill development and improvement. Results are discussed relative to the peer review literature and with consideration of the importance of professional skills needed by successful scientists and peer reviewers.

Comparison of Multiple Breath Washout and Spirometry in Children with Primary Ciliary Dyskinesia and Cystic Fibrosis and Healthy Controls.

Rationale: In cystic fibrosis (CF), the lung clearance index (LCI), derived from multiple breath washout (MBW), is more sensitive in detecting early lung disease than FEV1; MBW has been less thoroughly evaluated in young patients with primary ciliary dyskinesia (PCD).Objectives: Our objectives were 1) to evaluate the sensitivity of MBW and spirometry for the detection of mild lung disease in young children with PCD and CF compared with healthy control (HC) subjects and 2) to compare patterns of airway obstruction between disease populations.Methods: We used a multicenter, single-visit, observational study in children with PCD and CF with a forced expiratory volume in 1 second (FEV1) greater than 60% predicted and HC subjects, ages 3-12 years. Nitrogen MBW and spirometry were performed and overread for acceptability. χ2 and Kruskall-Wallis tests compared demographics and lung function measures between groups, linear regression evaluated the effect of disease state, and Spearman's rank correlation coefficient compared the LCI and spirometric measurements.Results: Twenty-five children with PCD, 49 children with CF, and 80 HC children were enrolled, among whom 17 children with PCD (68%), 36 children with CF (73%), and 53 (66%) HC children performed both acceptable spirometry and MBW; these children made up the analytic cohort. The median age was 9.0 years (interquartile range [IQR], 6.8-11.1). The LCI was abnormal (more than 7.8) in 10 of 17 (59%) patients with PCD and 21 of 36 (58%) patients with CF, whereas FEV1 was abnormal in three of 17 (18%) patients with PCD and six of 36 (17%) patients with CF. The LCI was significantly elevated in patients with PCD and CF compared with HC subjects (ratio of geometric mean vs. HC: PCD 1.27; 95% confidence interval [CI], 1.15-1.39; and CF 1.24; 95% CI, 1.15-1.33]). Children with PCD had lower midexpiratory-phase forced expiratory flow % predicted compared with children with CF (62% [IQR, 50-78%] vs. 85% [IQR, 68-99%]; P = 0.05). LCI did not correlate with FEV1.Conclusions: The LCI is more sensitive than FEV1 in detecting lung disease in young patients with PCD, similar to CF. LCI holds promise as a sensitive endpoint for the assessment of early PCD lung disease.

Predictors of response to proton pump inhibitor therapy among children with significant esophageal eosinophilia.

OBJECTIVES: To determine predictors of histological response to proton pump inhibitor (PPI) therapy among children with significant esophageal eosinophilia (SEE), defined as >or=15 eosinophils per high powered field (eos/hpf) on esophageal mucosal biopsy (EMB). STUDY DESIGN: Response to PPI therapy among children with SEE treated with PPI who underwent repeat EMB was studied retrospectively. Response was defined as <5 eos/hpf on repeat EMB. Characteristics of responders and nonresponders were analyzed. RESULTS: Of 326 patients (ages 1 through 18 years) diagnosed with SEE over a 7-year period, 43 (mean age, 8.5 years; 67% males) met inclusion criteria. After PPI therapy, 17 patients (40%) were responders. There were no significant differences in demographics, presenting symptoms, endoscopic, or histological findings between responders and nonresponders. Among patients with 15 to 20 eos/hpf on EMB, 50% were responders; among patients with >20 eos/hpf on EMB, 29% were responders. Seven of 17 (41%) patients with abnormal pH monitoring and 5 of 11 (45%) patients with normal monitoring were responders. CONCLUSIONS: Forty percent of patients with SEE demonstrated histological response to PPI therapy. None of the clinical characteristics evaluated predicted response, and response was not dependent on results of pH study. The role of PPI therapy in treating SEE warrants further prospective investigation.

The clinical utility of lung clearance index in early cystic fibrosis lung disease is not impacted by the number of multiple-breath washout trials.

The lung clearance index (LCI) from the multiple-breath washout (MBW) test is a promising surveillance tool for pre-school children with cystic fibrosis (CF). Current guidelines for MBW testing recommend that three acceptable trials are required. However, success rates to achieve these criteria are low in children aged <7 years and feasibility may improve with modified pre-school criteria that accepts tests with two acceptable trials. This study aimed to determine if relationships between LCI and clinical outcomes of CF lung disease differ when only two acceptable MBW trials are assessed. Healthy children and children with CF aged 3-6 years were recruited for MBW testing. Children with CF also underwent bronchoalveolar lavage fluid collection and a chest computed tomography scan. MBW feasibility increased from 46% to 75% when tests with two trials were deemed acceptable compared with tests where three acceptable trials were required. Relationships between MBW outcomes and markers of pulmonary inflammation, infection and structural lung disease were not different between tests with three acceptable trials compared with tests with two acceptable trials. This study indicates that pre-school MBW data from two acceptable trials may provide sufficient information on ventilation distribution if three acceptable trials are not possible.

Multiple-Breath Washout Outcomes Are Sensitive to Inflammation and Infection in Children with Cystic Fibrosis.

RATIONALE: The lung clearance index is a measure of ventilation distribution derived from the multiple-breath washout technique. The lung clearance index is increased in the presence of lower respiratory tract inflammation and infection in infants with cystic fibrosis; however, the associations during the preschool years are unknown. OBJECTIVES: We assessed the ability of the lung clearance index to detect the presence and extent of lower respiratory tract inflammation and infection in preschool children with cystic fibrosis. METHODS: Ventilation distribution outcomes were assessed at 82 visits with 58 children with cystic fibrosis and at 38 visits with 31 healthy children aged 3-6 years. Children with cystic fibrosis also underwent bronchoalveolar lavage fluid collection for detection of lower respiratory tract inflammation and infection. Associations between multiple-breath washout indices and the presence and extent of airway inflammation and infection were assessed using linear mixed effects models. RESULTS: Lung clearance index was elevated in children with cystic fibrosis (mean [SD], 8.00 [1.45]) compared with healthy control subjects (6.67 [0.56]). In cystic fibrosis, the lung clearance index was elevated in individuals with lower respiratory tract infections (difference compared with uninfected [95% confidence interval], 0.62 [0.06, 1.18]) and correlated with the extent of airway inflammation. CONCLUSIONS: These data suggest that the lung clearance index may be a useful surveillance tool for monitoring the presence and extent of lower airway inflammation and infection in preschool children with cystic fibrosis.

Association of Antibiotics, Airway Microbiome, and Inflammation in Infants with Cystic Fibrosis.

RATIONALE: The underlying defect in the cystic fibrosis (CF) airway leads to defective mucociliary clearance and impaired bacterial killing, resulting in endobronchial infection and inflammation that contributes to progressive lung disease. Little is known about the respiratory microbiota in the early CF airway and its relationship to inflammation. OBJECTIVES: To examine the bacterial microbiota and inflammatory profiles in bronchoalveolar lavage fluid and oropharyngeal secretions in infants with CF. METHODS: Infants with CF from U.S. and Australian centers were enrolled in a prospective, observational study examining the bacterial microbiota and inflammatory profiles of the respiratory tract. Bacterial diversity and density (load) were measured. Lavage samples were analyzed for inflammatory markers (interleukin 8, unbound neutrophil elastase, and absolute neutrophil count) in the epithelial lining fluid. RESULTS: Thirty-two infants (mean age, 4.7 months) underwent bronchoalveolar lavage and oropharyngeal sampling. Shannon diversity strongly correlated between upper and lower airway samples from a given subject, although community compositions differed. Microbial diversity was lower in younger subjects and in those receiving daily antistaphylococcal antibiotic prophylaxis. In lavage samples, reduced diversity correlated with lower interleukin 8 concentration and absolute neutrophil count. CONCLUSIONS: In infants with CF, reduced bacterial diversity in the upper and lower airways was strongly associated with the use of prophylactic antibiotics and younger age at the time of sampling; less diversity in the lower airway correlated with lower inflammation on bronchoalveolar lavage. Our findings suggest modification of the respiratory microbiome in infants with CF may influence airway inflammation.

Regenerative medicine: a radical reappraisal of the spleen.

The spleen has long been considered a dispensable organ. Recent research, however, has found that the spleen of adult mice holds a reservoir of stem cells that can rapidly and robustly differentiate into functional cells of diverse lineages. Splenic stem cells express Hox11, a key embryonic transcription factor that regulates organogenesis. The presence of multi-lineage stem cells in the spleen might represent lifelong persistence of cells from a primitive embryonic region called the aorta-gonad-mesonephros. By bringing together findings from diverse disciplines, we propose that the adult spleen is an important source of multi-lineage stem cells for future cellular therapies for diabetes and other diseases.

A role for transcription factor NF-kappaB in autoimmunity: possible interactions of genes, sex, and the immune response.

Sex hormones have long been implicated in autoimmune diseases because women account for 80% of cases. The mechanism of hormonal action in autoimmunity is unknown. Drawing on genetic studies of autoimmune disease, this article discusses how both genes and sex hormones may exert their effects through the same general mechanism, dysregulation of transcription factor NF-kappaB, an immunoregulatory protein. Gene and hormone alterations of the NF-kappaB signaling cascade provide a unifying hypothesis to explain the wide-ranging human and murine autoimmune disease phenotypes regulated by NF-kappaB, including cytokine balance, antigen presentation, lymphoid development, and lymphoid repertoire selection by apoptosis.

A summary of the FDA-NIMH-MATRICS workshop on clinical trial design for neurocognitive drugs for schizophrenia.

OBJECTIVE: On April 23, 2004, a joint meeting of the FDA, NIMH, MATRICS investigators, and experts from academia and the pharmaceutical industry was convened to develop guidelines for the design of clinical trials of cognitive-enhancing drugs for neurocognitive impairments in patients with schizophrenia. METHOD: Experts were asked to address specific questions relating to clinical trial design of adjunctive/co-treatment and broad spectrum agents. At the workshop, experts reviewed relevant evidence before offering the discussion panel proposed guidelines for a given subset of questions. The discussion panel, which consisted of presenters and representatives from FDA, NIMH, academia, and industry, deliberated to reach consensus on suggested guidelines. When evidence was insufficient, suggested guidelines represent the opinion of a cross-section of the presenters and discussion panel. RESULTS: Guidelines were developed for inclusion criteria, the use of co-primary outcome measures, and statistical approaches for study design. Consensus was achieved regarding diagnostic and concomitant medication inclusion criteria and on the use of cognitive screening measures. A key guideline was to limit the trial to patients in the residual phase of their illness, who have a predefined level of positive, negative, and affective symptoms. The most difficult issues were the feasibility of including a co-primary measure of functional improvement and the choice of comparator agent for a trial of a broad spectrum agent (with antipsychotic and cognitive-enhancing effects). CONCLUSIONS: The suggested guidelines represent reasonable starting points for trial design of cognitive-enhancing drugs, with the understanding that new data, subsequent findings, or other methodological considerations may lead to future modifications.

Diabetes and stem cell researchers turn to the lowly spleen.

The spleen gets no respect. Long seen as superfluous, the adult spleen of the mouse has recently been shown to hold stem cells that, in diabetic mice or genetically altered mice that lack a pancreas, effectively regenerate insulin-producing islet cells of the pancreas. Stem cells of the spleen express Hox11, a highly conserved transcription factor that plays a major role in the development of organs in vertebrate and invertebrate embryos. Hox11 and other members of the Hox family of genes may give stem cells of the spleen the capacity to mature into cell types other than islet cells, including neurons and bone cells. Multilineage splenic stem cells may trace to the embryogenesis and possible persistence into adulthood of a fetal stem cell region called the aorta-gonad-mesonephros (AGM). This Perspective calls for reappraisal of the lowly spleen for treating diabetes and other diseases of aging.