Chronic interstitial lung diseases in children: diagnosis approaches

Pediatric Diffuse Lung Disease in Infants: Imaging Findings and Histopathologic Correlation

Childhood interstitial lung disease (chILD) encompasses a diverse group of genetic, infectious, and inflammatory conditions affecting infants and children. The recognition and understanding of these entities have highlighted the necessity for more accurate classification. This group of rare heterogeneous diseases comprises more than 200 different conditions and has a combined estimated prevalence of less than one patient per 100 000 children. Hence, a systematic diagnostic approach is crucial. This article describes a diagnostic approach for pediatric diffuse lung diseases in infancy, including an analysis of clinical presentations and imaging and histologic features to effectively distinguish among various chILD entities. Although they often have overlapping and nonspecific radiologic features, some chILD entities may exhibit typical imaging findings, resulting in a CT diagnosis or aiding in narrowing the differential diagnosis, thus guiding the clinician to the appropriate genetic tests, potentially limiting unnecessary biopsies. This approach aims to enhance the understanding and diagnosis of chILD in infants, thereby facilitating improved patient care.

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 Challenging Diagnosis of Interstitial Lung Disease in Children-One Case Report and Literature Review

Childhood interstitial lung disease (chILD) includes a heterogeneous spectrum of rare respiratory disorders in children associated with substantial morbi-mortality. Interstitial tissue, and other pulmonary structures, epithelium, blood vessels, or pleura are involved, resulting in a restrictive lung disfunction. Respiratory symptoms set in progressively and are often subtle, making thorough clinical history and physical examination fundamental. The etiology often is obscure. The clinical presentation mimics pneumonia or asthma, leading to a diagnostic delay. Challenging diagnosis may require genetic tests, bronchoalveolar lavage, or lung biopsy. Alongside general supportive therapeutic measures, anti-inflammatory, immunosuppressive or antifibrotic agents may be used, based on data derived from adult studies. However, if accurate diagnosis and treatment are delayed, irreversible chronic respiratory failure may ensue, impacting prognosis. The most frequent chILD is hypersensitivity pneumonitis (HP), although it is rare in children. HP is associated with exposure to an environmental antigen, resulting in inflammation of the airways. Detailed antigen exposure history and identification of the inciting trigger are the cornerstones of diagnostic. This article provides the current state of chILD, revealing specific features of HP, based on a clinical case report of a patient admitted in our clinic, requiring extensive investigations for diagnosis, with a favorable long-term outcome.

Interstitial lung disease in infancy and early childhood: a clinicopathological primer

Children's interstitial lung disease (chILD) encompasses a wide and heterogeneous spectrum of diseases substantially different from that of adults. Established classification systems divide chILD into conditions more prevalent in infancy and other conditions occurring at any age. This categorisation is based on a multidisciplinary approach including clinical, radiological, genetic and histological findings. The diagnostic evaluation may include lung biopsies if other diagnostic approaches failed to identify a precise chILD entity, or if severe or refractory respiratory distress of unknown cause is present. As the majority of children will be evaluated and diagnosed outside of specialist centres, this review summarises relevant clinical, genetic and histological findings of chILD to provide assistance in clinical assessment and rational diagnostics.

ILD of childhood is comparable by name only to lung disease in adults. A dedicated interdisciplinary team is required to achieve the best possible outcome. This review summarises the current clinicopathological criteria and associated genetic alterations.https://bit.ly/3mpxI3b

RaDiCo, the French national research program on rare disease cohorts

BACKGROUND

Rare diseases (RDs) affect nearly 3 million people in France and at least 26-30 million people in Europe. These diseases, which represent a major medical concern, are mainly of genetic origin, often chronic, progressive, degenerative, life threatening and disabling, accounting for more than one third of all deaths occurring during infancy. In this context, there are needs for coordinated information on RDs at national/international levels, based on high quality, interoperable and sharable data. The main objective of the RaDiCo (Rare Disease Cohorts) program, coordinated by Inserm, was the development of RD e-cohorts via a national platform. The cohort projects were selected through a national call in 2014. The e-cohorts are supported by an interoperable platform, equivalent to an infrastructure, constructed on the "cloud computing" principle and in compliance with the European General Data Protection Regulation. It is dedicated to allow a continuous monitoring of data quality and consistency, in line with the French Health Data Hub.

RESULTS

Depending on cohorts, the objectives are to describe the natural history of the studied RD(s), identify the underlying disease genes, establish phenotype-genotype correlations, decipher their pathophysiology, assess their societal and medico-economic impact, and/or identify patients eligible for new therapeutic approaches. Inclusion of prevalent and incident cases started at the end of 2016. As of April 2021, 5558 patients have been included within 13 RD e-cohorts covering 67 diseases integrated in 10 European Reference Networks and contributing to the European Joint Program on RDs. Several original results have been obtained in relation with the secondary objectives of the RaDiCo cohorts. They deal with discovery of new disease genes, assessment of treatment management, deciphering the underlying pathophysiological mechanisms, diagnostic approaches, genotype-phenotype relationships, development and validation of questionnaires relative to disease burden, or methodological aspects.

CONCLUSION

RaDiCo currently hosts 13 RD e-cohorts on a sharable and interoperable platform constructed on the "cloud computing" principle. New RD e-cohorts at the European and international levels are targeted.

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

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.

Atractylenolide III attenuates bleomycin-induced experimental pulmonary fibrosis and oxidative stress in rat model via Nrf2/NQO1/HO-1 pathway activation

BACKGROUND

Bleomycin (BLM) is a chemotherapy drug used to treat cancer, one of which side effects is that it can lead to pulmonary fibrosis (PF). Atractylenoide III (AtrIII), derived from the dried roots of rhizoma atractylodis of compositae, is one of the main active substances of rhizoma atractylodis. It has anti-inflammatory, anti-tumor and other effects. This study aimed to investigate whether AtrIII alleviated BLM-induced PF and oxidative stress in rats through the nuclear factor erythroid-2-related factor 2/NQO1,NAD(P)H:quinine oxidoreductase 1/Heme oxygenase-1 (Nrf2/NQO1/HO-1) pathway.

METHODS

A BLM-induced pulmonary fibrosis model in SD rats was established. The respiratory dynamics were evaluated by using Wholebody flow-through plethysmography. Lung injury and pulmonary fibrosis were observed by Hematoxylin-eosin (HE) and Masson staining. Apoptosis was assay by Tunel assay. Inflammatory factors were detected with commercial kits. Expression of mRNAs and proteins were detected by RT-qPCR and Western blot, respectively.

RESULTS

AtrIII (1.2, 2.4 mg/kg) improved the lung injury and lung function in the BLM-induced Sprague-Dawley (SD) rats. AtrIII reduced the apoptosis rate and protein expression of Caspase-3 and Caspase-9. AtrIII (1.2, 2.4 mg/kg) decrease the pulmonary fibrosis damage and protein expression transforming growth factor-β (TGF-β) and α-smooth muscle actin (α-SMA). AtrIII also down-regulated the levels of interleukin 6 (IL-6), inductible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α), while up-regulated the level of IL-10 in peripheral blood serum. Moreover, AtrIII (1.2, 2.4 mg/kg) increased the activity of superoxide dismutase (SOD) and glutathione (GSH), while decreased the malondialdehyde (MDA) content and lactate dehydrogenase (LDH) activity. AtrIII (1.2, 2.4 mg/kg) increased the levels of Nrf2, NQO1 and HO-1. In addition, AtrIII reversed the effects of Nrf2 interference on pulmonary fibrosis damage, decreased SOD and GSH activity, and increased MDA content.

CONCLUSION

AtrIII could attenuate the pulmonary fibrosis and reliev oxidative stress through the Nrf2/NQO1/ HO-1 pathway.

Interstitial Lung Disease in Rare Congenital Syndromes

Diffuse or interstitial lung disease (DLD/ILD) comprises a diverse group of disorders that involve the pulmonary parenchyma. Its aetiology varies (which makes the diagnostic process difficult), but congenital diseases, including malformation syndromes or developmental disorders, constitute one of the causative factors. They are rare conditions, and thus their frequency is not high. However, considering the progress and increasing availability of genetic testing, detection of these rare syndromes may increase. The aim of this work is, therefore, to present the symptomatology of selected congenital syndromes with ILD, taking into account the genetic background.

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.

Pulmonary Fibrosis in Children

: Pulmonary fibrosis (PF) is a very rare condition in children, which may be observed in specific forms of interstitial lung disease. None of the clinical, radiological, or histological descriptions used for PF diagnosis in adult patients, especially in situations of idiopathic PF, can apply to pediatric situations. This observation supports the view that PF expression may differ with age and, most likely, may cover distinct entities. The present review aims at summarizing the current understanding of PF pathophysiology in children and identifying suitable diagnostic criteria.