Pediatric Pulmonology 2022 year in review: Rare and diffuse lung disease

The field of rare and diffuse pediatric lung disease continues to evolve and expand rapidly as clinicians and researchers make advancements in the diagnosis and treatment of children's interstitial and diffuse lung disease, non-cystic fibrosis bronchiectasis, and primary ciliary dyskinesia. Papers published on these topics in Pediatric Pulmonology and other journals in 2022 describe newly recognized disorders, elucidate disease mechanisms and courses, explore potential biomarkers, and assess novel treatments. In this review, we will discuss these important advancements and place them in the context of existing literature.

The US national registry for childhood interstitial and diffuse lung disease: Report of study design and initial enrollment cohort

INTRODUCTION

Childhood interstitial and diffuse lung disease (chILD) encompasses a broad spectrum of rare disorders. The Children's Interstitial and Diffuse Lung Disease Research Network (chILDRN) established a prospective registry to advance knowledge regarding etiology, phenotype, natural history, and management of these disorders.

METHODS

This longitudinal, observational, multicenter registry utilizes single-IRB reliance agreements, with participation from 25 chILDRN centers across the U.S. Clinical data are collected and managed using the Research Electronic Data Capture (REDCap) electronic data platform.

RESULTS

We report the study design and selected elements of the initial Registry enrollment cohort, which includes 683 subjects with a broad range of chILD diagnoses. The most common diagnosis reported was neuroendocrine cell hyperplasia of infancy, with 155 (23%) subjects. Components of underlying disease biology were identified by enrolling sites, with cohorts of interstitial fibrosis, immune dysregulation, and airway disease being most commonly reported. Prominent morbidities affecting enrolled children included home supplemental oxygen use (63%) and failure to thrive (46%).

CONCLUSION

This Registry is the largest longitudinal chILD cohort in the United States to date, providing a powerful framework for collaborating centers committed to improving the understanding and treatment of these rare disorders.

CpG methylation patterns in placenta and neonatal blood are differentially associated with neonatal inflammation

BACKGROUND

Infants born extremely premature are at increased risk for health complications later in life for which neonatal inflammation may be a contributing biological driver. Placental CpG methylation provides mechanistic information regarding the relationship between prenatal epigenetic programming, prematurity, neonatal inflammation, and later-in-life health.

METHODS

We contrasted CpG methylation in the placenta and neonatal blood spots in relation to neonatal inflammation in the Extremely Low Gestational Age Newborn (ELGAN) cohort. Neonatal inflammation status was based on the expression of six inflammation-related proteins, assessed as (1) day-one inflammation (DOI) or (2) intermittent or sustained systemic inflammation (ISSI, inflammation on ≥2 days in the first 2 postnatal weeks). Epigenome-wide CpG methylation was assessed in 354 placental samples and 318 neonatal blood samples.

RESULTS

Placental CpG methylation displayed the strongest association with ISSI (48 CpG sites) but was not associated with DOI. This was in contrast to CpG methylation in blood spots, which was associated with DOI (111 CpG sites) and not with ISSI (one CpG site).

CONCLUSIONS

Placental CpG methylation was strongly associated with ISSI, a measure of inflammation previously linked to later-in-life cognitive impairment, while day-one neonatal blood methylation was associated with DOI.

IMPACT

Neonatal inflammation increases the risk of adverse later-life outcomes, especially in infants born extremely preterm. CpG methylation in the placenta and neonatal blood spots were evaluated in relation to neonatal inflammation assessed via circulating proteins as either (i) day-one inflammation (DOI) or (ii) intermittent or sustained systemic inflammation (ISSI, inflammation on ≥2 days in the first 2 weeks). Tissue specificity was observed in epigenetic-inflammatory relationships: placental CpG methylation was associated with ISSI, neonatal blood CpG methylation was associated with DOI. Supporting the placental origins of disease framework, placental epigenetic patterns are associated with a propensity for ISSI in neonates.

Pediatric pulmonology 2021 year in review: Rare and diffuse lung disease

The field of rare and diffuse pediatric lung disease is experiencing rapid progress as diagnostic and therapeutic options continue to expand. In this annual review, we discuss manuscripts published in Pediatric Pulmonology in 2021 in (1) children's interstitial and diffuse lung disease, (2) congenital airway and lung malformations, and (3) noncystic fibrosis bronchiectasis including primary ciliary dyskinesia. These include case reports, descriptive cohorts, trials of therapies, animal model studies, and review articles. The results are put into the context of other literature in the field. Each furthers the field in important ways, while also highlighting the continued need for further studies.

Collaborative decision-making: A framework for decision-making about life-sustaining treatments in children with medical complexity

OBJECTIVE

Caregivers of children with medical complexity (CMC) face decisions about life-sustaining treatments (LST) like tracheostomy. We sought to develop a clinically relevant and realistic model for decision-making about tracheostomy placement that might apply to other LST in CMC.

DESIGN

This qualitative study, conducted between 2013 and 2015, consisted of 41 interviews with 56 caregivers of CMC who had received tracheostomies and 5 focus groups of 33 healthcare providers (HCPs) at a tertiary-care children's hospital in North Carolina. Participants were asked about their perspectives on the tracheostomy decision-making process. Data were transcribed, and coded. Using thematic content analysis, we inductively developed a tracheostomy decision-making framework and process.

RESULTS

Many factors influenced caregivers' decisions, including children's well-being and caregivers' values, faith, knowledge, experience, emotional state, and social factors; preserving the child's life was the most important. HCPs consider many clinical and nonclinical factors; recommending tracheostomy for children with limited survival, perceived poor functioning and quality of life, and progressive conditions is ethically difficult. The framework of tracheostomy decision-making has inter-related caregiver- and HCP-level factors that influence the process. The framework contains elements not captured in a shared decision-making model, but better fits a collaborative decision-making (CDM) model. The tracheostomy CDM process that emerged from the data has two nonsequential components that HCPs could use: (1) gaining understanding and (2) holding decision-making conversations.

CONCLUSIONS

CDM could be a useful model for clinicians guiding families about tracheostomy for CMC. The applicability of CDM for decision-making about other LSTs needs further exploration.

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.

Tracheostomy decision-making for children with medical complexity: What supports and resources do caregivers need?

OBJECTIVES

Caregivers of children with medical complexity (CMC) face decisions about life-sustaining interventions, such as tracheostomy. Our objective is to describe the support needs of caregivers of CMC and the resources they use surrounding tracheostomy decision-making (TDM) for their children.

METHODS

This qualitative study, conducted between 2013 and 2015, consisted of semi-structured interviews with 56 caregivers of 41 CMC who had tracheostomies, and 5 focus groups of 33 clinicians at a tertiary care children's hospital. Participants were asked about their perspectives on the TDM process. Qualitative data were transcribed, coded, and organized into themes.

RESULTS

Caregivers used five domains of resources surrounding TDM: (1) social network including extended family members, friends, and clergy; (2) healthcare providers including physicians and nurses; (3) other parents of children with tracheostomy; (4) tangible materials such as print materials, videos, tracheostomy tubes, mannequins, and simulation labs; and (5) internet including websites, social media, and online health communities. Caregivers used these resources for (1) decision-making, (2) becoming knowledgeable and skillful about child's diagnosis, tracheostomy, and home care, and (3) emotional and spiritual well-being. Caregivers agreed that they received enough support, but there were gaps. Clinicians were knowledgeable about these resources, discussed social network and internet less often than the other domains, and identified gaps in supporting caregivers.

SIGNIFICANCE OF RESULTS

Caregivers' need for support and use of resources surrounding tracheostomy placement for CMC extended beyond decision-making, and included becoming knowledgeable and getting emotional/spiritual support. Healthcare providers exploring these resources with caregivers could improve the quality of TDM communication.

Pediatric pulmonology 2020 year in review: Rare and diffuse lung disease

Pediatric Pulmonology publishes original research, review articles, and case reports on topics related to a wide range of children's respiratory disorders. Here we review some of the most notable manuscripts published in 2020 in this journal on (1) children's interstitial lung disease (chILD), (2) congenital airway and lung anomalies, and (3) primary ciliary dyskinesia and other non-cystic fibrosis bronchiectasis. The articles reviewed are discussed in context with published works from other journals.

Interstitial lung disease in children with Rubinstein-Taybi syndrome

INTRODUCTION

Rubinstein-Taybi syndrome (RSTS) is a rare genetic syndrome caused primarily by a mutation in the CREBBP gene found on chromosome 16. Patients with RSTS are at greater risk for a variety of medical problems, including upper airway obstruction and aspiration. Childhood interstitial lung disease (ILD) thus far has not been definitively linked to RSTS. Here we present three patients with RSTS who developed ILD and discuss possible mechanisms by which a mutation in CREBBP may be involved in the development of ILD.

METHODS

Routine hematoxylin and eosin staining was performed on lung biopsy tissue for histological analysis. Immunofluorescent staining was performed on lung biopsy tissue for markers of fibrosis, surfactant deficiency and histone acetylation. Cases 1 and 2 had standard clinical microarray analysis. Case 3 had whole exome sequencing. Bioinformatics analyses were performed to identify possible causative genes using ToppGene.

RESULTS

Computed tomography images in all cases showed consolidated densities overlying ground glass opacities. Lung histopathology revealed accumulation of proteinaceous material within alveolar spaces, evidence of fibrosis, and increased alveolar macrophages. Immunofluorescent staining showed increase in surfactant protein C staining, patchy areas of increased anti-smooth muscle antibody staining, and increased staining for acetylated histone 2 and histone 3 lysine 9.

DISCUSSION

Clinical characteristics, radiographic imaging, lung histopathology, and immunofluorescent staining results shared by all cases demonstrated findings consistent with ILD. Immunofluorescent staining suggests two possible mechanisms for the development of ILD: abnormal surfactant metabolism and/or persistent activation of myofibroblasts. These two pathways could be related to dysfunctional CREBBP protein.

The Role of Childhood Asthma in Obesity Development: A Nationwide US Multicohort Study

RATIONALE

Asthma and obesity often co-occur. It has been hypothesized that asthma may contribute to childhood obesity onset.

OBJECTIVES

To determine if childhood asthma is associated with incident obesity and examine the role of asthma medication in this association.

METHODS

We studied 8,716 children between ages 6 and 18.5 years who were nonobese at study entry participating in 18 US cohorts of the Environmental influences on Child Health Outcomes program (among 7,299 children with complete covariate data mean [SD] study entry age = 7.2 [1.6] years and follow up = 5.3 [3.1] years).

MEASUREMENTS AND MAIN RESULTS

We defined asthma based on caregiver report of provider diagnosis. Incident obesity was defined as the first documented body mass index ≥95th percentile for age and sex following asthma status ascertainment. Over the study period, 26% of children had an asthma diagnosis and 11% developed obesity. Cox proportional hazards models with sex-specific baseline hazards were fitted to assess the association of asthma diagnosis with obesity incidence. Children with asthma had a 23% (95% confidence intervals [CI] = 4, 44) higher risk for subsequently developing obesity compared with those without asthma. A novel mediation analysis was also conducted to decompose the total asthma effect on obesity into pathways mediated and not mediated by asthma medication use. Use of asthma medication attenuated the total estimated effect of asthma on obesity by 64% (excess hazard ratios = 0.64; 95% CI = -1.05, -0.23).

CONCLUSIONS

This nationwide study supports the hypothesis that childhood asthma is associated with later risk of obesity. Asthma medication may reduce this association and merits further investigation as a potential strategy for obesity prevention among children with asthma.

Pulmonary surveillance in pediatric hematopoietic stem cell transplant: A multinational multidisciplinary survey

Background

Hematopoietic Stem Cell Transplant (HSCT) is an established treatment for malignant and non‐malignant conditions and pulmonary disease is a leading cause of late term morbidity and mortality. Accurate and early detection of pulmonary complications is a critical step in improving long term outcomes. Existing guidelines for surveillance of pulmonary complications post‐HSCT contain conflicting recommendations.

Aim

To determine the breadth of current practice in monitoring for pulmonary complications of pediatric HSCT.

Methods

An institutional review board approved, online, anonymous multiple‐choice survey was distributed to HSCT and pulmonary physicians from the United States of America and Australasia using the REDcap platform. The survey was developed by members of the American Thoracic Society Working Group on Complications of Childhood Cancer, and was designed to assess patient management and service design.

Results

A total of 40 (34.8%) responses were received. The majority (62.5%) were pulmonologists, and 82.5% were from the United States of America. In all, 67.5% reported having a protocol for monitoring pulmonary complications and 50.0% reported adhering “well” or “very well” to protocols. Pulmonary function tests (PFTs) most commonly involved spirometry and diffusion capacity for carbon monoxide. The frequency of PFTs varied depending on time post‐HSCT and presence of complications. In all, 55.0% reported a set threshold for a clinically significant change in PFT.

Conclusions

These results illustrate current variation in surveillance for pulmonary complications of pediatric HSCT. The results of this survey will inform development of future guidelines for monitoring of pulmonary complications after pediatric HSCT.

Pediatric pulmonology 2019 year in review: rare and diffuse lung disease

Pediatric Pulmonology publishes original research, review articles, and case reports on topics related to a wide range of children's respiratory disorders. Here we review manuscripts published in 2019 in this journal and others on (1) anatomic lung, airway, and vascular malformations, (2) children's interstitial lung disease, and (3) primary ciliary dyskinesia and non-cystic fibrosis bronchiectasis.

Decision-Making About Tracheostomy for Children With Medical Complexity: Caregiver and Health Care Provider Perspectives

OBJECTIVE

Caregivers of children with medical complexity (CMC) face decisions about tracheostomy. The objectives of this paper are to identify facilitators and barriers to tracheostomy decision-making (TDM) process for CMC.

METHODS

Using phenomenology as its methodologic orientation, this qualitative study conducted in North Carolina between 2013 and 2015 consists of semistructured interviews with 56 caregivers of 41 CMC who received tracheostomies, and 5 focus groups of 33 health care providers (HCP) at a tertiary care children's hospital involved in TDM for CMC. Participants were asked to share their experiences and perspectives on the TDM process. Qualitative data were transcribed, coded, and organized into themes as is consistent with thematic content analysis.

RESULTS

Five themes were identified. 1) Caregivers perceived decision about tracheostomy for their children was theirs to make. 2) Strategies that increased caregivers' active participation in the TDM process facilitated the TDM process. 3) Caregiver emotional stress and lack of understanding about tracheostomy were barriers. 4) Good HCP communication during the TDM process was valued; poor communication was a barrier. 5) Collaboration among HCP-facilitated TDM, especially when nurses were involved, whereas fragmentation in care was a barrier.

CONCLUSIONS

Caregivers take a primary role in the TDM process. Many caregiver and HCP-level facilitators and barriers for TDM exist. Augmenting the facilitators and reducing the barriers identified in this study could improve the TDM process for CMC.

Pediatric Pulmonology Year in Review 2018: Rare lung disease, neuromuscular disease, and diagnostic testing

Pediatric Pulmonology publishes original research, case reports, and review articles on topics related to a wide range of children's respiratory disorders. In this article, we highlight the past year's publications in the topic areas of rare lung diseases, respiratory complications of neuromuscular disorders, and diagnostic testing, as well as selected literature in these areas from other journals.

Pediatric pulmonology year in review 2017: Part 1

Pediatric Pulmonology publishes original research, case reports and review articles on topics related to a wide range of children's respiratory disorders. In this article (Part 1 of a series), we summarize the past year's publications in our major topic areas, as well as selected literature in these areas from other journals. In Part 1, we review selected articles on diagnostic testing/endoscopy, respiratory complications of neuromuscular disorders, and rare lung diseases.

Pediatric metabolic outcome comparisons based on a spectrum of obesity and asthmatic symptoms

RATIONALE

Asthma and obesity are 2 of the most prevalent public health issues for children in the U.S. Trajectories of both have roughly paralleled one another over the past several decades causing many to explore their connection to one another and to other associated health issues such as diabetes and dyslipidemia. Earlier models have commonly designated obesity as the central hub of these associations; however, more recent models have argued connections between pediatric asthma and other obesity-related metabolic conditions regardless of children's obesity risk.

OBJECTIVES

To examine the relationships between asthma, obesity, and abnormal metabolic indices.

METHODS

We conducted a cross-sectional study of 179 children ages 7 to 12 years recruited from a rural, Appalachian region. Our model controlled for children's smoke exposure, body mass index percentile, and gender to examine the association between children's asthma (based on pulmonary function tests, medical history, medications, and parent report of severity), lipids (fasting lipid profile), and measures of altered glucose metabolism (glycosylated hemoglobin and homeostatic model assessment 2-insulin resistance).

RESULTS

Our findings revealed a statistically significant model for low density lipids, high density lipids, log triglyceride, and homeostatic model assessment 2-insulin resistance; however, Asthma had a significant effect for the mean triglycerides. We also found an asthma-obesity interaction effect on children's glycosylated hemoglobin with asthmatic obese children revealing significantly higher glycosylated hemoglobin values than non-asthmatic obese children.

CONCLUSIONS

Our findings support a connection between asthma and children's glycosylated hemoglobin values; however, this association remains entwined with obesity factors.

Pediatric Pulmonology year in review 2016: Part 1

Pediatric Pulmonology continues to publish research and clinical topics related to the entire range of children's respiratory disorders. As we have done annually in recent years, we here summarize the past year's publications in our major topic areas, as well as selected literature in these areas from other core journals relevant to our discipline. This review (Part 1) covers selected articles on sleep, diagnostic testing/endoscopy, respiratory complications of neuromuscular disorders, and rare lung diseases.

Familial neuroendocrine cell hyperplasia of infancy

BACKGROUND

Neuroendocrine cell hyperplasia of infancy (NEHI) is a recently described children's interstitial lung disease (chILD) disorder of unknown etiology. It manifests clinically with tachypnea, retractions, hypoxemia, and crackles. The characteristic radiographic appearance consists of pulmonary hyperexpansion and ground-glass densities on high-resolution computed tomography (HRCT). Lung histology shows hyperplasia of bombesin-immunopositive neuroendocrine cells within distal bronchioles and alveolar ducts without other identifiable lung pathology or developmental anomaly.

METHODS

We describe four families with multiple siblings diagnosed with NEHI. Cases were identified at three pediatric centers. Inclusion criteria included clinical findings consistent with NEHI, lung biopsy confirmation in the index case, and a diagnostic HRCT or biopsy in other siblings.

RESULTS

Each family had a proband diagnosed with NEHI based upon pathologic review, and at least one additional sibling diagnosed either by pathologic review or HRCT. All patients presented between 2 and 15 months of age. Both male and female children were affected. The majority of the patients underwent both HRCT and lung biopsy. There were no deaths among affected children. No environmental exposures or other potential etiologies were identified as a cause of presenting symptoms.

CONCLUSIONS

The familial occurrence of NEHI suggests the possibility of a genetic etiology for this disorder and highlights the importance of taking a complete family medical history for infants presenting with a suggestive clinical picture. Identification of familial NEHI patients allows for the opportunity to further our understanding of this disorder, its natural history, the phenotypic spectrum, and potential genetic causes.