Childhood interstitial lung diseases in immunocompetent children in Australia and New Zealand: a decade's experience

Childhood Interstitial Lung Diseases: Lessons Learned From 15-Year Observation at a Polish Referral Center

BACKGROUND

Childhood interstitial lung diseases (chILD) are rare, chronic lung diseases characterized by symptoms such as tachypnea, dyspnea, hypoxemia, crackles, and diffuse parenchymal abnormalities on chest imaging.

OBJECTIVE

To evaluate the etiologic spectrum, clinical presentation, management, and outcomes of chILD at a Polish referral center.

METHODS

We retrospectively reviewed data from patients (0-18 years) diagnosed with chILD, admitted to the Department of Pediatric Pulmonology and Allergy, Medical University of Warsaw, from June 2009 to February 2024, classified according to the chILD-EU categorization system.

RESULTS

A total of 275 patients (65.5% male) were included, with a median age at diagnosis of 13 months (range: 1-221). Persistent tachypnea of infancy (PTI)/neuroendocrine cell hyperplasia of infancy (NEHI) was the most common diagnosis (52.4%), followed by disorders related to systemic diseases (11.3%) and related to exposures (10.2%). 13.8% of diseases remained undefined. The predominant symptoms included crackles (81.5%), dyspnea (72.7%) and tachypnea (68.3%). All children underwent chest computed tomography. Bronchoscopy, genetic testing, and lung biopsy were performed in 46.2%, 34.9%, and 21.4% of cases, respectively. Most children (92.7%) received some form of treatment, including inhaled bronchodilators/steroids (68.8%), systemic steroids (26.5%), long-term macrolides (16.3%), and immunosuppressants (11.6%). Oxygen supplementation and nutritional support were required in 50.5% and 29.8% of patients, respectively. At a median follow-up of 31.5 months, 92.9% of patients achieved clinical improvement or stabilization, and 6.2% deteriorated, including seven deaths. The 5-year survival rate was 95.66%.

CONCLUSION

This study highlights the significant diversity within chILD, with PTI/NEHI being the most common condition.

Genetic Testing Utilization in the U.S. Registry for Childhood Interstitial and Diffuse Lung Diseases

INTRODUCTION

Childhood interstitial and diffuse lung diseases (chILD) comprise a diverse group of rare disorders. Identifying the underlying cause is crucial for treatment, prognosis, and estimating recurrence risk. The objective of this study was to assess the utilization of genetic testing for subjects enrolled in the United States National Registry for ChILD, a multicenter observational study.

METHODS

Genetic data from participating sites were reviewed and analyzed in relationship to clinical characteristics.

RESULTS

Of 609 children enrolled from 22 centers, genetic testing was performed for 55.5% (n = 338). Genetic testing results were positive (diagnostic) for 22.8% (n = 77), negative for 60.7% (n = 205), and uncertain for 16.6% (n = 56). Most testing was performed through gene panels (55.9%), followed by exome sequencing (ES) or whole genome sequencing (WGS) (26.9%), single gene testing (24.6%), and/or chromosomal microarray (11.8%). For participants with positive (diagnostic) genetic testing results, the majority were diagnosed through gene panel (33.8%; n = 26) or single gene testing (32.5%; n = 25). The most common diagnosis confirmed by genetic testing was SFTPC-associated surfactant metabolism dysfunction. Of the 59 subjects with unclassified ILD, only 22% (n = 13) had undergone ES or WGS, 61% (n = 36) had received panel testing, and 27% (n = 16) did not have any genetic testing reported.

CONCLUSION

The utilization of genetic testing has been variable in infants and children enrolled in the ChILD Registry. Additional efforts are needed to develop genetic testing recommendations for children with suspected ILD. Furthermore, there is opportunity for broader utilization of ES/WGS and genetic discovery for children with lung disease of unclear etiology.

An update on diagnosis and treatments of childhood interstitial lung diseases

Childhood interstitial lung diseases (chILDs) are rare and heterogeneous disorders associated with significant morbidity and mortality. The clinical presentation of chILD typically includes chronic or recurrent respiratory signs and symptoms with diffuse radiographic abnormalities on chest imaging. Diagnosis requires a structured, multi-step approach. Treatment options are limited, with disease-specific therapies available only in selected cases and management relying primarily on supportive care. Awareness of chILDs has been steadily increasing. New diagnoses, advanced diagnostic tests, and novel treatments are emerging each year, highlighting the importance of collaborative, multidisciplinary teams in providing comprehensive care for children and families affected by these complex conditions. On behalf of the European Respiratory Society Clinical Research Collaboration for chILD (ERS CRC chILD-EU), this review provides an updated overview of the diagnostic approach and management strategies for chILDs.

Engraftment of wild-type alveolar type II epithelial cells in surfactant protein C deficient mice

Childhood interstitial lung disease (chILD) secondary to pulmonary surfactant deficiency is a devastating chronic lung disease in children. Clinical presentation includes mild to severe respiratory failure and fibrosis. There is no specific treatment, except lung transplantation, which is hampered by a severe shortage of donor organs, especially for young patients. Repair of lungs with chILD represents a longstanding therapeutic challenge but cell therapy is a promising strategy. As surfactant is produced by alveolar type II epithelial (ATII) cells, engraftment with normal or gene-corrected ATII cells might provide an avenue to cure. Here we used a chILD disease-like model, Sftpc -/- mice, to provide proof-of-principle for this approach. Sftpc -/- mice developed chronic interstitial lung disease with age and were hypersensitive to bleomycin. We could engraft wild-type ATII cells after low dose bleomycin conditioning. Transplanted ATII cells produced mature SPC and attenuated bleomycin-induced lung injury up to two months post-transplant. This study demonstrates that partial replacement of mutant ATII cells can promote lung repair in a mouse model of chILD-like disease.

Clinical scope and healthcare utilization in childhood interstitial lung disease at a tertiary center

Childhood interstitial lung disease (chILD) is a heterogeneous group of diffuse lung diseases that can be challenging to diagnose. With relative rarity of individual entities, data are limited on disease prevalence, care patterns, and healthcare utilization. The objective of this study was to evaluate chILD prevalence and review diagnostic and clinical care patterns at our center. A single-center, retrospective cohort study was conducted of patients receiving care at the Children's Hospital of Philadelphia (CHOP) between 1 January 2019 and 31 December 2021. Through query of selected ICD-10 billing codes relevant for chILD and medical chart review, a total of 306 patients were identified receiving pulmonary care during this period. Respiratory symptom onset was documented to have developed before 2 years of age for 40% of cases. The most common diagnostic categories included those with oncologic disease (21.2%), bronchiolitis obliterans (10.1%), and connective tissue disease (9.5%). Genetic testing was performed in 49% of cases, while 36% underwent lung biopsy. Hospitalization at CHOP had occurred for 80.4% of patients, with 45.1% ever hospitalized in an intensive care unit. One-third of children had required chronic supplemental oxygen. Seven (2.3%) patients died during this 3-year period. Collectively, these data demonstrate the scope of chILD and extent of health care utilization at a large volume tertiary care center. This approach to cohort identification and EMR-driven data collection in chILD provides new opportunities for cohort analysis and will inform the feasibility of future studies.

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.

Learning to make a difference for chILD: Value creation through network collaboration and team science

Addressing the recognized challenges and inequalities in providing high quality healthcare for rare diseases such as children's interstitial lung disease (chILD) requires collaboration across institutional, geographical, discipline, and system boundaries. The Children's Interstitial Lung Disease Respiratory Network of Australia and New Zealand (chILDRANZ) is an example of a clinical network that brings together multidisciplinary health professionals for collaboration, peer learning, and advocacy with the goal of improving the diagnosis and management of this group of rare and ultra-rare conditions. This narrative review explores the multifaceted benefits arising from social learning spaces within rare disease clinical networks by applying the value creation framework. The operation of the chILDRANZ network is used as an example across the framework to highlight how value is generated, realized, and transferred within such collaborative clinical and research networks. The community of practice formed in the chILDRANZ multidisciplinary meetings provides a strong example of social learning that engages with the uncertainty inherent in rare disease diagnosis and management and pays attention to generate new knowledge and best practice to make a difference for children and families living with chILD. This review underscores international calls for further investment in, and support of, collaborative clinical networks and virtual centers of excellence for rare disease.

Approach to the patient with Childhood Interstitial and Diffuse Lung Disease

Childhood Interstitial and Diffuse Lung Disease (chILD) encompasses a group of rare, chronic lung disorders in infants and children with overlapping clinical features but diverse etiologies. The clinical presentation of chILD is of chronic or recurring respiratory signs and symptoms, often including increased work of breathing and hypoxia, with diffuse radiographic abnormalities on chest imaging. Recognition can be challenging since some clinical features overlap with those of more common pediatric respiratory diseases including asthma and recurrent viral infections, among others. chILD should be considered as an underlying diagnosis when a patient's respiratory symptoms seem disproportionate to the clinical scenario and/or persist. The diagnostic process involves multiple steps and is tailored to the individual patient. Nearly all children will undergo imaging and pulmonary function testing, many will undergo bronchoscopy with bronchoalveolar lavage, many will receive genetic testing, and some will require lung biopsy. Treatment includes preventive care, evaluation for comorbidities, pharmacotherapy according to diagnosis, and ongoing disease surveillance, including revisiting genetic and histopathologic results as new clinical information becomes available and as our understanding of these rare disorders improves. The purpose of this review is to provide a broad approach to the diagnosis and management of patients with chILD.

Innovations in Childhood Interstitial and Diffuse Lung Disease

Children's interstitial and diffuse lung diseases (chILDs) are a heterogenous and diverse group of lung disorders presenting during childhood. Infants and children with chILD disorders present with respiratory signs and symptoms as well as diffuse lung imaging abnormalities. ChILD disorders are associated with significant health care resource utilization and high morbidity and mortality. The care of patients with chILD has been improved through multidisciplinary care, multicenter collaboration, and the establishment of patient research networks in the United Stated and abroad. This review details past and current innovations in the diagnosis and clinical care of children with chILD.

Epidemiology of childhood interstitial lung disease in France: the RespiRare cohort

INTRODUCTION

Interstitial lung disease in children (chILD) are rare and mostly severe lung diseases. Very few epidemiological data are available in limited series of patients. The aim of this study was to assess the prevalence and incidence of chILD in France.

METHODS

We performed within the RespiRare network a multicentre retrospective observational study in patients with chILD from 2000 to 2022 and a prospective evaluation of chILD's incidence between February 2022 and 2023.

RESULTS

chILD was reported in 790 patients in 42 centres. The estimated 2022 prevalence in France was 44 /million children (95% CI 40.76 to 47.46) and the computed incidence was 4.4 /million children (95% CI 3.44 to 5.56). The median age at diagnosis was 3 months with 16.9% of familial forms. Lung biopsy and genetic analyses were performed in 23.4% and 76.9%, respectively. The most frequent chILD aetiologies in the <2 years group were surfactant metabolism disorders (16.3%) and neuroendocrine cell hyperplasia of infancy (11.8%), and in the 2-18 years group diffuse alveolar haemorrhage (12.2%), connective tissue diseases (11.4%), hypersensitivity pneumonitis (8.8%) and sarcoidosis (8.8%). The management included mainly oxygen therapy (52%), corticosteroid pulses (56%), oral corticosteroids (44%), azithromycin (27.2%), enteral nutrition (26.9%), immunosuppressants (20.3%) and hydroxychloroquine (15.9%). The 5-year survival rate was 57.3% for the patients diagnosed before 2 years and 86% between 2 and 18 years.

CONCLUSION

This large and systematic epidemiological study confirms a higher incidence and prevalence of chILD than previously described. In order to develop international studies, efforts are still needed to optimise the case collection and to harmonise diagnostic and management practices.

Incidence, prevalence, and pattern of medical service utilization of children's rare lung diseases in South Korea

INTRODUCTION

Children's rare lung diseases are a heterogeneous group of rare lung diseases with significant morbidity and mortality. There is very limited information on the incidence and prevalence of children's rare lung diseases in Asia. We investigated the nationwide incidence, prevalence, and pattern of medical service utilization of children's rare lung diseases in Korea.

METHODS

We studied patients who were diagnosed with rare lung diseases coded per International Statistical Classification of Diseases and Related Health Problems, 10th Edition and registered in the national rare diseases database of confirmed patients. Data was extracted from the Korean National Health Insurance Service Claims database over 2019-2021.

RESULTS

Average incidence rate was 12.9 new cases per million children per year, and average prevalence rate was 60.2 cases per million children during the study period of 2019-2021. We found that more than 65% of new cases were diagnosed before 2 years of age. ChILD, primary ciliary dyskinesia, and cystic fibrosis were usually diagnosed after 6 years of age. Congenital airway and lung anomalies were often diagnosed before 2 years of age. Busan and Gyeongsangnam-do residents tended to visit hospitals near their place of residence, while residents of other areas tended to visit hospitals in Seoul regardless of their area of residence.

CONCLUSIONS

We examined the epidemiology of rare lung diseases in children in South Korea. Our estimation of the incidence and prevalence could be used for sustainable health care and equitable distribution of health care resources.

Diagnostic workup of childhood interstitial lung disease

Childhood interstitial lung diseases (chILDs) are rare and heterogeneous diseases with significant morbidity and mortality. An accurate and quick aetiological diagnosis may contribute to better management and personalised treatment. On behalf of the European Respiratory Society Clinical Research Collaboration for chILD (ERS CRC chILD-EU), this review summarises the roles of the general paediatrician, paediatric pulmonologists and expert centres in the complex diagnostic workup. Each patient's aetiological chILD diagnosis must be reached without prolonged delays in a stepwise approach from medical history, signs, symptoms, clinical tests and imaging, to advanced genetic analysis and specialised procedures including bronchoalveolar lavage and biopsy, if necessary. Finally, as medical progress is fast, the need to revisit a diagnosis of "undefined chILD" is stressed.

The role of exome sequencing in childhood interstitial or diffuse lung disease

BACKGROUND

Children's interstitial and diffuse lung disease (chILD) is a complex heterogeneous group of lung disorders. Gene panel approaches have a reported diagnostic yield of ~ 12%. No data currently exist using trio exome sequencing as the standard diagnostic modality. We assessed the diagnostic utility of using trio exome sequencing in chILD. We prospectively enrolled children meeting specified clinical criteria between 2016 and 2020 from 16 Australian hospitals. Exome sequencing was performed with analysis of an initial gene panel followed by trio exome analysis. A subset of critically ill infants underwent ultra-rapid trio exome sequencing as first-line test.

RESULTS

36 patients [median (range) age 0.34 years (0.02-11.46); 11F] were recruited from multiple States and Territories. Five patients had clinically significant likely pathogenic/pathogenic variants (RARB, RPL15, CTCF, RFXANK, TBX4) and one patient had a variant of uncertain significance (VIP) suspected to contribute to their clinical phenotype, with VIP being a novel gene candidate.

CONCLUSIONS

Trio exomes (6/36; 16.7%) had a better diagnostic rate than gene panel (1/36; 2.8%), due to the ability to consider a broader range of underlying conditions. However, the aetiology of chILD in most cases remained undetermined, likely reflecting the interplay between low penetrant genetic and environmental factors.

The diagnostic odyssey: insights from parents of children living with an undiagnosed condition

Background

People living with rare disease often have protracted journeys towards diagnosis. In the last decade, programs have arisen around the world that are dedicated to ending this ‘diagnostic odyssey’, including the Undiagnosed Diseases Program Western Australia (UDP-WA), which has a focus on finding diagnoses for children and young adults. To explore the lived experience of the diagnostic journey semi-structured interviews were conducted with parents of 11 children at commencement of their involvement in the UDP-WA.

Results

Thematic analysis revealed three main themes that captured parents’ experiences and perspectives. Parents reported (i) the need to respond to significant care needs of their children, which span not only the health system but other systems such as education and disability services. In doing so, parents become the navigator, expert and advocate for their children. Meanwhile, parents are on (ii) the diagnostic odyssey—the rollercoaster of their journey towards diagnosis, which includes various names applied to their child’s condition, and the impact of no diagnosis. Parents described their views on (iii) the value of a diagnosis and the outcomes they expect to be associated with a diagnosis.

Conclusion

Analysis showed an overall significant perceived value of a diagnosis. Our study provides new perspectives on the concept of diagnosis and indicates that parents may benefit from supports for their child’s care needs that are beyond the scope of the UDP-WA.

Pediatric hypersensitivity pneumonitis: literature update and proposal of a diagnostic algorithm

Hypersensitivity pneumonitis (HP) is a rare disease in childhood with the prevalence of 4 cases per 1 million children and an incidence of 2 cases per year. The average age of diagnosis at pediatric age is approximately 10 years. The pathogenesis of HP is characterized by an immunological reaction caused by recurrent exposure to triggering environmental agents (mostly bird antigens in children). The clinical picture of HP is complex and variable in children, often presenting in subacute forms with cough and exertion dyspnea. A diagnosis of HP should be considered in patients with an identified exposure to a triggering antigen, respiratory symptoms, and radiologic signs of interstitial lung disease. Blood tests and pulmonary function tests (PFT) support the diagnosis. Bronchoscopy (with bronchoalveolar lavage and tissue biopsy) may be needed in unclear cases. Antigen provocation test is rarely required. Of note, the persistence of symptoms despite various treatment regimens may support HP diagnosis. The avoidance of single/multiple triggers is crucial for effective treatment. No evidence- based guidelines for treatment are available; in particular, the role of systemic glucocorticoids in children is unclear. With adequate antigen avoidance, the prognosis in children with HP is generally favorable.

Etiologic Classification of Diffuse Parenchymal (Interstitial) Lung Diseases

Interstitial lung diseases (ILD) or diffuse parenchymal lung diseases (DPLD) comprise a large number of disorders. Disease definition and classification allow advanced and personalized judgements on clinical disease, risks for genetic or environmental transmissions, and precision medicine treatments. Registers collect specific rare entities and use ontologies for a precise description of complex phenotypes. Here we present a brief history of ILD classification systems from adult and pediatric pneumology. We center on an etiologic classification, with four main categories: lung-only (native parenchymal) disorders, systemic disease-related disorders, exposure-related disorders, and vascular disorders. Splitting diseases into molecularly defined entities is key for precision medicine and the identification of novel entities. Lumping diseases targeted by similar diagnostic or therapeutic principles is key for clinical practice and register work, as our experience with the European children’s ILD register (chILD-EU) demonstrates. The etiologic classification favored combines pediatric and adult lung diseases in a single system and considers genomics and other -omics as central steps towards the solution of “idiopathic” lung diseases. Future tasks focus on a systems’ medicine approach integrating all data and bringing precision medicine closer to the patients.

Childhood Interstitial Lung Disease in an Immunocompetent Patient Without Exposure

Childhood interstitial and diffuse lung disease (chILD) is a heterogeneous group of rare and chronic respiratory disorders with an estimated prevalence of 1.5 cases per million children aged 0-18 years. Various etiologies for chILD include but are not limited to systemic diseases, medications, exposure to tobacco, metabolic disorders, and organ diseases. Presented is the case of an immunocompetent young girl who presented with symptoms of recurrent cough and clubbing and was found to have interstitial lung disease.

Cellular Therapy for the Treatment of Paediatric Respiratory Disease

Respiratory disease is the leading cause of death in children under the age of 5 years old. Currently available treatments for paediatric respiratory diseases including bronchopulmonary dysplasia, asthma, cystic fibrosis and interstitial lung disease may ameliorate symptoms but do not offer a cure. Cellular therapy may offer a potential cure for these diseases, preventing disease progression into adulthood. Induced pluripotent stem cells, mesenchymal stromal cells and their secretome have shown great potential in preclinical models of lung disease, targeting the major pathological features of the disease. Current research and clinical trials are focused on the adult population. For cellular therapies to progress from preclinical studies to use in the clinic, optimal cell type dosage and delivery methods need to be established and confirmed. Direct delivery of these therapies to the lung as aerosols would allow for lower doses with a higher target efficiency whilst avoiding potential effect of systemic delivery. There is a clear need for research to progress into the clinic for the treatment of paediatric respiratory disease. Whilst research in the adult population forms a basis for the paediatric population, varying disease pathology and anatomical differences in paediatric patients means a paediatric-centric approach must be taken.

Study design of a randomised, placebo-controlled trial of nintedanib in children and adolescents with fibrosing interstitial lung disease

Childhood interstitial lung disease (chILD) comprises >200 rare respiratory disorders, with no currently approved therapies and variable prognosis. Nintedanib reduces the rate of forced vital capacity (FVC) decline in adults with progressive fibrosing interstitial lung diseases (ILDs). We present the design of a multicentre, prospective, double-blind, randomised, placebo-controlled clinical trial of nintedanib in patients with fibrosing chILD (1199-0337 or InPedILD; ClinicalTrials.gov: NCT04093024).

Male or female children and adolescents aged 6–17 years (≥30; including ≥20 adolescents aged 12–17 years) with clinically significant fibrosing ILD will be randomised 2:1 to receive oral nintedanib or placebo on top of standard of care for 24 weeks (double-blind), followed by variable-duration nintedanib (open-label). Nintedanib dosing will be based on body weight-dependent allometric scaling, with single-step dose reductions permitted to manage adverse events. Eligible patients will have evidence of fibrosis on high-resolution computed tomography (within 12 months of their first screening visit), FVC ≥25% predicted, and clinically significant disease (Fan score of ≥3 or evidence of clinical progression over time). Patients with underlying chronic liver disease, significant pulmonary arterial hypertension, cardiovascular disease, or increased bleeding risk are ineligible. The primary endpoints are pharmacokinetics and the proportion of patients with treatment-emergent adverse events at week 24. Secondary endpoints include change in FVC% predicted from baseline, Pediatric Quality of Life Questionnaire, oxygen saturation, and 6-min walk distance at weeks 24 and 52. Additional efficacy and safety endpoints will be collected to explore long-term effects.

We describe the design of #InPedILD, a study of 24 weeks’ nintedanib or placebo on top of standard of care, followed by variable-duration open-label nintedanib in children with interstitial lung disease (ClinicalTrials.gov NCT04093024) #PedILDhttps://bit.ly/3tC1a7P

Spectrum of childhood interstitial and diffuse lung diseases at a tertiary hospital in Egypt

Background

Childhood interstitial and diffuse lung diseases (chILD) encompass a broad spectrum of rare pulmonary disorders. In most developing Middle Eastern countries, chILD is still underdiagnosed. Our objective was to describe and investigate patients diagnosed with chILD in a tertiary university hospital in Egypt.

Methods

We analysed data of consecutive subjects (aged <18 years) referred for further evaluation at the Children's Hospital, Ain Shams University (Cairo, Egypt). Diagnosis of chILD was made in accordance with the ChILD-EU criteria. The following information was obtained: demographic data, clinical characteristics, chest computed tomography findings, laboratory studies, spirometry, bronchoalveolar lavage and histopathology findings.

Results

22 subjects were enrolled over 24 months. Median age at diagnosis was 7 years (range 3.5–14 years). The most common manifestations were dyspnoea (100%), cough (90.9%), clubbing (95.5%) and tachypnoea (90.9%). Systematic evaluation led to the following diagnoses: hypersensitivity pneumonitis (n=3), idiopathic interstitial pneumonias (n=4), chILD related to chronic granulomatous disease (n=3), chILD related to small airways disease (n=3), post-infectious chILD (n=2), Langerhans cell histiocytosis (n=2), idiopathic pulmonary haemosiderosis (n=2), granulomatous lymphocytic interstitial lung disease (n=1), systemic sclerosis (n=1) and familial interstitial lung disease (n=1). Among the subjects who completed the diagnostic evaluation (n=19), treatment was changed in 13 (68.4%) subjects.

Conclusion

Systematic evaluation and multidisciplinary peer review of chILD patients at our tertiary hospital led to changes in management in 68% of the patients. This study highlights the need for an Egyptian chILD network with genetic testing, as well as the value of collaborating with international groups in improving healthcare for children with chILD.

In Egypt, childhood interstitial and diffuse lung diseases (chILD) are still underdiagnosed. Establishment of an Egyptian chILD network with genetic testing is essential to improve healthcare for children diagnosed with chILD.https://bit.ly/385qKsU

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.

Children's Interstitial and Diffuse Lung Diseases (ChILD) in 2020

The term children interstitial lung diseases (chILD) refers to a heterogeneous group of rare diseases that diffusely affect the lung. ChILD specific to children younger than 2 years of age include diffuse developmental disorders, growth abnormalities, specific conditions of undefined etiology (neuroendocrine cell hyperplasia of infancy and pulmonary interstitial glycogenosis) and surfactant protein disorders. Clinical manifestations are highly variable, ranging from the absence of relevant symptoms to a severe onset. Most commonly, chILD presents with nonspecific respiratory signs and symptoms, such as dyspnea, polypnea, dry cough, wheezing, recurrent respiratory infections and exercise intolerance. In the diagnostic approach to a child with suspected ILD, chest high resolution computed tomography and genetic tests play a central role. Then, if the diagnosis remains uncertain, laryngotracheal-bronchoscopy and lung biopsy are needed. Pharmacological treatment is mostly empiric and based on anti-inflammatory and immunomodulatory drugs including corticosteroids, hydroxychloroquine and azithromycin. Despite chILD overall rarity, pediatric pulmonologists must be familiar with these diseases in order to carry out a timely diagnosis and patient treatment.

Interstitial lung diseases in children

Interstitial lung disease (ILD) in children (chILD) is a heterogeneous group of rare respiratory disorders that are mostly chronic and associated with high morbidity and mortality. The pathogenesis of the various chILD is complex and the diseases share common features of inflammatory and fibrotic changes of the lung parenchyma that impair gas exchanges. The etiologies of chILD are numerous. In this review, we chose to classify them as ILD related to exposure/environment insults, ILD related to systemic and immunological diseases, ILD related to primary lung parenchyma dysfunctions and ILD specific to infancy. A growing part of the etiologic spectrum of chILD is being attributed to molecular defects. Currently, the main genetic mutations associated with chILD are identified in the surfactant genes SFTPA1, SFTPA2, SFTPB, SFTPC, ABCA3 and NKX2-1. Other genetic contributors include mutations in MARS, CSF2RA and CSF2RB in pulmonary alveolar proteinosis, and mutations in TMEM173 and COPA in specific auto-inflammatory forms of chILD. However, only few genotype-phenotype correlations could be identified so far. Herein, information is provided about the clinical presentation and the diagnosis approach of chILD. Despite improvements in patient management, the therapeutic strategies are still relying mostly on corticosteroids although specific therapies are emerging. Larger longitudinal cohorts of patients are being gathered through ongoing international collaborations to improve disease knowledge and targeted therapies. Thus, it is expected that children with ILD will be able to reach the adulthood transition in a better condition.

Approaching Clinical Trials in Childhood Interstitial Lung Disease and Pediatric Pulmonary Fibrosis

Childhood interstitial lung disease (chILD) comprises a spectrum of rare diffuse lung disorders. chILD is heterogeneous in origin, with different disease manifestations occurring in the context of ongoing lung development. The large number of disorders in chILD, in combination with the rarity of each diagnosis, has hampered scientific and clinical progress within the field. Epidemiologic and natural history data are limited. The prognosis varies depending on the etiology, with some forms progressing to lung transplant or death. There are limited treatment options for patients with chILD. Although U.S. Food and Drug Administration-approved treatments are now available for adult patients with idiopathic pulmonary fibrosis, no clinical trials have been conducted in a pediatric population using agents designed to treat lung fibrosis. This review will focus on progressive chILD disorders and on the urgent need for meaningful objective outcome measures to define, detect, and monitor fibrosis in children.

Nebulized step-down budesonide vs. fluticasone in infantile asthma: A retrospective cohort study

The United States Food and Drug Administration has approved budesonide in infantile asthma but nebulization of infants under budesonide has the risk of relapse of asthma. The objective of the present study was to compare the effectiveness and safety of fluticasone step-down treatment with budesonide step-down treatment in infantile asthma. The data of 778 infants with confirmed asthma were included in the analysis. Infants who had received nebulized 500 µg budesonide twice daily for 6 weeks followed by 250 µg budesonide twice daily for 6 weeks were included in the BS group (n=389), while infants who had received nebulized 250 µg fluticasone twice daily for 6 weeks followed by 125 µg fluticasone twice daily for 6 weeks were included in the FC group (n=389). The data of lung function tests and a safety study were collected and analyzed. Budesonide treatment achieved a reduced specific airway resistance (sRaw; 1.28±0.11 vs. 1.21±0.10 kPa/sec; P<0.0001, q=13.45) and improved forced expiratory volume in 1 sec (FEV1; 0.977±0.068 vs. 0.997±0.085 l/sec; P<0.0001, q=5.54). In addition, fluticasone treatment achieved a reduced sRaw (1.27±0.1 vs. 1.23±0.11 kPa/sec, P<0.0001, q=7.39) and improved FEV1 (0.971±0.069 vs. 0.992±0.085 l/sec; P=0.0003, q=5.46). Of note, the efficacy of budesonide to reduce sRaw (P=0.008, q=3.69) and improve FEV1 (P<0.0001, q=6.93) was greater than that of fluticasone. The budesonide treatment group had more post-treatment symptom-free days than the fluticasone treatment group (165.56±23.15 vs. 112.21±9.45 days; P<0.0001). The step-down approach of budesonide nebulization may better support the functional and clinical outcomes with an increased number of post-treatment symptom-free days compared with fluticasone in infantile asthma (level of evidence, 3).

Childhood diffuse parenchymal lung diseases: We need a new classification

INTRODUCTION

Childhood diffuse parenchymal lung diseases (DPLD) are a heterogeneous group of respiratory disorders of both known and unknown causes that share common histological features. To date, there is not an exact consensus about the terminology, classification, therapy and follow up of this disease because of its rarity and wide clinical spectrum.

OBJECTIVES

In this study, we tried to classify our DPLD patients according to the last classification scheme (chILD Network Classification).

METHODS

The files of the children diagnosed with DPLD at our university hospital between 1974 and 2012 were retrospectively investigated. Clinical features, laboratory, radiological and histopathological findings, therapy and follow-up outcomes of these patients were recorded and evaluated according to the actual information and definitions.

RESULTS

We described 130 DPLD patients, the largest childhood DPLD series from a single center, classified in 16 distinct groups according to their diagnosis. Our largest group in this serie is pulmonary hemosiderosis (28.5%); idiopathic interstitial pneumonias, pulmonary hemosiderosis, sarcoidosis and lipid storage diseases with lung involvement represent the 70% of the diagnoses. When we classified our patients according to the chILD Network Classification; patients with idiopathic interstitial pneumonia older than 2 years, idiopathic pulmonary hemosiderosis, pulmonary alveolar microlithiasis and diffuse chondroid malformation of the lung stayed out of this classification.

CONCLUSION

To ensure a consensus about the therapy and follow up, we have to make revisions and reorganisations on the DPLD classification which was proposed in 2007. We need a new childhood DPLD classification that will cover all these disease groups.

Abandoning developmental silos: what can paediatricians and adult interstitial lung disease physicians learn from each other?

PURPOSE OF REVIEW

Interstitial lung disease (ILD) consists of a large and heterogeneous group of disorders that are classified together because of similar clinical, radiographic, physiologic or pathologic manifestations. Overall, although there is overlap between adult and childhood ILD (chILD), there are many differences in disease causes and prevalences.

RECENT FINDINGS

In the last few years, our understanding of adult ILD pathobiology has improved substantially. This is particularly true for idiopathic pulmonary fibrosis, the most common of the idiopathic interstitial pneumonias, wherein recently developed guideline documents provide recommendations for the diagnosis and clinical management of patients. For chILD, similar guidelines are yet to be developed. However, complications and long-term pulmonary outcomes of paediatric disease are better appreciated, which make the implementation of a successful transition program from paediatric to adult care an urgent need. Similarly important is the development of guidelines on performance and interpretation of genetic testing in affected and unaffected relatives of familial cases and in children of adult-onset ILD patients. Lung transplantation appears to be as successful as in adult patients for end-stage disease. Paediatric pulmonologists should engage with the adult multidisciplinary teams and benefit from their much more extensive experience.

SUMMARY

Childhood and adult ILD share a number of aspects, which give children and adult ILD specialists exciting opportunities to collaborate and learn from each other. Such collaborative effort between child and adult ILD experts is crucial for successful future development in the field.

Genetic basis of surfactant dysfunction in Chinese children: A retrospective study

OBJECTIVE

To investigate the prevalence of surfactant dysfunction (SD) and the genotype distribution in Chinese childhood interstitial lung disease (chILD).

METHODS

From December 2013 to December 2016, whole exons and splicing regions of surfactant protein (SP)-B, SP-C, and adenosine triphosphate (ATP)-binding cassette subfamily A member 3 (ABCA3) were sequenced in chILD with unknown etiology in five children's medical centers of China. The sequencing was performed by Next-generation sequencing technique in a molecular genetics laboratory. The clinical and genetic data were reviewed retrospectively.

RESULTS

In total, 136 patients of age 3 months to 13 years (mean 12.5 ± 9.4 months) were recruited, among which 76 were males. Of the 136 cases of chILD, 13.2% (18 of 136) were diagnosed with SD. In these 18 SD cases, 15 had heterozygous SP-C deficiencies, two cases had compound heterozygous ABCA3 deficiencies, and no SP-B deficiency was identified. In SP-C deficiencies, there were six cases with p.I73T, 2 with p.I73N, 5 with p.V39L, 1 with c.417delA, and 1 case with IVS4, +1G>C. Two cases of ABCA3 mutation were heterozygous with c.1755delC and c.2890G>A; c.3913T>C (R1305W) and exon 13 to 18 deletion. One was negative by sequencing while diagnosed positive by pathology.

CONCLUSION

The proportion of genetic mutation of SD in chILD is 13.2% in China, of which SP-C deficiency is predominant. The mutation, SP-C p.V39L, was found to be relatively prevalent in China and warrants further investigation.

Health-related quality of life in infants and children with interstitial lung disease

INTRODUCTION

Interstitial lung disease in children (chILD) is a highly heterogeneous group of rare and severe respiratory disorders. The disease by itself, the burden of the treatments (oxygen therapy, corticosteroid pulses, nutritional support) and recurrent hospitalizations may impair the quality of life (QoL) of these children. The aim of the study was to compare the health-related QoL (HR-QoL) in chILD compared to a healthy population and to find out the predictive factors of an altered QoL.

METHODS

Patients aged 1 month to 18 years with ILD of known or unknown etiology were prospectively included. Parents and children over 8 years old were asked to fill the PedsQL 4.0 Generic Core Scale ranging from 0 to 100 points.

RESULTS

A total of 78 children were recruited in 13 French pediatric centers. Total scores were 11.94 points (P = 0.0003) less for child self-report and 14.08 points ( P < 0.0001) less for parent proxy-report with respect to the healthy population. The clinical factors associated with a lower total score were: extrapulmonary expression of the disease, higher Fan severity score, long-term oxygen therapy, nutritional support, and a number of oral treatments.

CONCLUSION

Using a validated quality of life (QoL) scale, we showed that health-related-QoL is significantly impaired in chILD compared with a healthy population. Factors altering QoL score are easy to recognize and could help identify children at a heightened risk of low QoL.

Chronic interstitial lung diseases in children: diagnosis approaches

Introduction: Children interstitial lung disease (chILD) is a heterogeneous group of rare respiratory disorders characterized by inflammatory and fibrotic changes of the lung parenchyma. They include ILD related to exposure/environment insults, ILD related to systemic diseases processes, ILD related to primary lung parenchyma dysfunctions and ILD specific to infancy. Areas covered: This review provides an update on chILD pathophysiology and diagnosis approaches in immunocompetent children. It includes current information on genetic causes. Expert commentary: ChILD covers a large spectrum of entities with heterogeneous disease expression. Various classifications have been reported, but none of them seems completely satisfactory. Recently, progress in molecular genetics has allowed identifying some genetic contributors, with, so far, a lack of correlations between gene disorders and disease expression. Despite improvements in patient management, chILD prognosis is still burdened by significant morbidity and mortality. Ongoing international collaborations will allow gathering larger longitudinal cohorts of patients to improve disease knowledge and personalized care. The overall goal is to help the children with ILD to reach the adulthood transition in a better condition, and to structure genetic counseling for their family.

Side effects of medications used to treat childhood interstitial lung disease

Interstitial lung disease in children (chILD) comprises a range of different rare diseases. There is limited evidence for the treatment of chILD and no randomised clinical trials of treatment have been undertaken. Most treatments are therefore prescribed off-label based on expert opinion. The off-label nature of prescription of drugs for chILD highlights the importance of a solid understanding of the side effects to facilitate risk-benefit assessment. The European Respiratory Society chILD guidelines recommend the use of systemic glucocorticosteroids, hydroxychloroquine and azithromycin. Side effects of these drugs will be discussed followed by consideration of other drugs used for the treatment of chILD.

Chronic interstitial lung disease in children

Children's interstitial lung diseases (chILD) are increasingly recognised and contain many lung developmental and genetic disorders not yet identified in adult pneumology. Worldwide, several registers have been established. The Australasian Registry Network for Orphan Lung Disease (ARNOLD) has identified problems in estimating rare disease prevalence; focusing on chILD in immunocompetent patients, a period prevalence of 1.5 cases per million children and a mortality rate of 7% were determined. The chILD-EU register highlighted the workload to be covered per patient included and provided protocols for diagnosis and initial treatment, similar to the United States chILD network. Whereas case reports may be useful for young physicians to practise writing articles, cohorts of patients can catapult progress, as demonstrated by recent studies on persistent tachypnoea of infancy, hypersensitivity pneumonitis in children and interstitial lung disease related to interferonopathies from mutations in transmembrane protein 173. Translational research has linked heterozygous mutations in the ABCA3 transporter to an increased risk of interstitial lung diseases, not only in neonates, but also in older children and adults. For surfactant dysfunction disorders in infancy and early childhood, lung transplantation was reported to be as successful as in adult patients. Mutual potentiation of paediatric and adult pneumologists is mandatory in this rapidly extending field for successful future development.

This brief review highlights publications in the field of paediatric interstitial lung disease as reviewed during the Clinical Year in Review session presented at the 2017 European Respiratory Society (ERS) Annual Congress in Milan, Italy. It was commissioned by the ERS and critically presents progress made as well as drawbacks.

Successful developments in chILD are register/consortia based and potentiate paediatric and adult pneumologyhttp://ow.ly/dgrO30hBbRJ