Pediatric interstitial lung disease revisited

Clinical features and outcomes of children's interstitial lung disease accompanied with connective tissue disease: A prospective cohort study

BACKGROUND

Medical complexity of childhood interstitial lung disease (chILD) with connective tissue disease (CTD) poses a considerable challenge to pediatricians.

METHODS

Clinical characteristics, laboratory findings, pulmonary function tests (PFTs), treatments and outcomes obtained for patients with CTD-chILD were analyzed in a prospective study.

RESULTS

Patients' median age at diagnosis was 7 years old. About 29.4% (15/51) suffered rapidly progressive childhood ILD (RP-chILD) with a high mortality rate (33.3%, 5/15), and the incidence of RP-chILD in juvenile idiopathic inflammatory myopathies was as high as 41.6% and the mortality rate was 30% (3/10). More than 70% patients had decreased diffusion capacity. The mean interval from symptoms-onset to diagnosis was 11.3 months. Compared to chILD with known CTD, the chILD proceeded CTD had a longer diagnosis interval, higher mortality, hospital stays and costs (P < 0.05). Lung imaging (33.3%) and lung function (72.7%) were partially reversible. The average survival time was 68.6 months. Cox univariate analysis showed that HRCT score ≥3, experiencing RP-chILD, cyanosis, acute respiratory distress syndrome (ARDS) and CD4 T cell <200 were significant predictors of death for chILD, whereas Cox multivariate analysis showed that ARDS was significant predictor of death for CTD-chILD, while IVIG support combined with corticosteroids and immunosuppressants was a protective factor.

CONCLUSIONS

Care providers should conduct an assessment for CTD in chILD as a longer interval between the diagnosis of chILD and the CTD is associated with increased mortality. Complications as ARDS predict poor outcome in CTD-chILD, while IVIG support combined with corticosteroids and immunosuppressants is a protective factor.

Interstitial Lung Disease in Neonates: A Long Road Is Being Paved

Background: Interstitial lung disease (ILD) is one of the most difficult conditions in pulmonology due to difficulties in diagnosing, classifying, and treating this condition. They require invasive approaches to diagnose (e.g., lung biopsy), non-applicable methods (e.g., lung function tests in newborns), or potentially non-accessible methods (e.g., genetic testing in not-well-equipped facilities, and several weeks are required for results to be announced). They represent a heterogeneous group of diseases in which the alveolar epithelium, parenchyma, and capillaries of the lungs are damaged, which leads to changes in the pulmonary interstitium, proliferation of connective tissue, and thickening of the alveolar-capillary membranes and alveolar septa. These changes are accompanied by impaired oxygen diffusion, progressive respiratory failure, and radiographic signs of bilateral dissemination. Although adult and child classifications for ILD have evolved over the years, classification for ILD in neonates remains a challenge. Case presentation: Here we discuss ILD in neonates briefly, and report two rare cases of ILD (a male white neonate, two-day-old with fibrosing alveolitis, and another male white neonate, one-day old with desquamative interstitial pneumonitis), with these diagnoses initially thought to be presented only in adulthood. Lung biopsy and histopathological findings of the two neonates have shown mononuclear cells in the alveolar spaces, and thickening of the alveolar walls confirmed the diagnosis of fibrosing alveolitis in one neonate, and desquamation of the large mononuclear cells in the intra-alveolar space in the other neonate, with the diagnosis of desquamative interstitial pneumonitis being confirmed. Interstitial lung disease lacks a consensus guideline on classification and diagnosis in neonates, rendering it one of the greatest challenges to pediatricians and neonatologists with remarkable morbidity and mortality rates. Conclusions: Fibrosing alveolitis and desquamative interstitial pneumonitis (DIP) are not adult-only conditions, although rare in neonates, histopathological examination and clinical practice can confirm the diagnosis. Based on our clinical practice, prenatal and maternal conditions may serve as potential risk factors for developing IDL in neonates, and further studies are needed to prove this hypothesis.

Characteristics of gastroesophageal reflux disease in children with interstitial lung disease

BACKGROUND

Childhood interstitial lung disease (chILD) is a rare group of respiratory tract disorders. One of the factors suggested to be associated with its etiopathogenesis is microaspiration related to gastroesophageal reflux disease (GERD). The aim of the present study was to determine the frequency and characteristics of GERD in children with chILD, with a particular focus on proximal GER episodes.

METHODS

This was a prospective cross-sectional study. Consecutive patients with chILD underwent 24-h multichannel intraluminal pH-impedance monitoring. Different types of gastroesophageal reflux episodes (GER) were recorded and compared with regard to the GERD diagnosis.

RESULTS

Sixty-two children (median age of 1.22 years) were included. GERD was diagnosed in 20 (32.3%) of them. The GERD (+) and GERD (-) subgroups differed mainly in their esophageal exposure to acid content (2.9 vs. 1.0%, p = 0.02) and bolus exposure (3.0 vs. 1.4%, p < 0.0001), as well as total number of GER (72.5 vs. 42.0 p = 0.0004), acid GER (35.5 vs. 15.0 p = 0.004), and acid proximal GER (21.0 vs. 12.0 p = 0.02). There were no differences in the number of proximal GER comparing GERD (+) and GERD (-) subgroups.

CONCLUSIONS

The frequency of GERD seems to be relatively high in the population of children with chILD used in this study. However, it has not demonstrated an association between proximal GER and GERD diagnosis in chILD, which casts uncertainty over the microaspiration theory proposed to link the two diseases. The latter conclusion, however, needs to be confirmed using more accurate aspiration assessment methods.

Childhood interstitial lung disease more prevalent in infancy: a practical review

Childhood interstitial lung disease (chILD) is a heterogeneous group of uncommon, mostly chronic pediatric pulmonary disorders characterized by impaired gas exchange and diffuse abnormalities on imaging. A subset of these diseases occurs more frequently in infants and young children than in older children and teenagers. Some of these disorders occur in certain clinical scenarios and/or have typical imaging features that can help the radiologist recognize when to suggest a possible diagnosis and potentially spare a child a lung biopsy. We review the clinical, histopathological and computed tomography features of chILD more prevalent in infancy, including diffuse developmental disorders, growth abnormalities, specific conditions of undefined etiology, and surfactant dysfunction mutations and related disorders, to familiarize the pediatric radiologist with this group of disorders.

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.

Role of surfactant protein C in neonatal genetic disorders of the surfactant system: A case report

RATIONALE

Respiratory distress syndrome (RDS) refers to the symptoms of progressive dyspnea and respiratory failure in newborns shortly after birth. The clinical and genetic characteristics of patients with neonatal RDS have not been extensively reported.

PATIENT CONCERNS

A infant was in critical condition with repeated paroxysmal blood oxygen decline. Oxygen inhalation and noninvasive ventilator-assisted breathing relief were not effective. The etiology was unclear, and there was no family history of lung disease. Surface-active substance replacement therapy and positive pressure-assisted ventilation support were ineffective.

DIAGNOSIS

The infant was clinically diagnosed with RDS. Genetic tests revealed a heterozygous missense mutation in the c.168 surfactant protein C (SFTPC) gene.

INTERVENTIONS

Tracheal intubation was performed with invasive ventilator-assisted breathing, pulmonary surfactant was administered. Supportive treatment for liver protection and administration of a cardiotonic diuretic, vasodilator, human immunoglobulin (intravenous infusion), fresh frozen plasma, and suspended red blood cells were performed.

OUTCOMES

The infant showed poor responses to respiratory and circulatory support, antibiotic treatment, and other treatment methods. The patient was discharged from hospital against the advice of us, cut off from us. The long-term prognosis of the patient after discharge remains unknown.

LESSONS

SFTPC gene mutations may be an important risk factor for the development of common lung diseases. Because of the important roles of surfactant functions and metabolism, mutations in these genes can affect the production and function of pulmonary surfactant, leading to severe lung disease in term newborns.

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 Lung MRI: Currently Available and Emerging Techniques

OBJECTIVE. The purpose of this article is to review currently available and emerging techniques for pediatric lung MRI for general radiologists. CONCLUSION. MRI is a radiation-free alternative to CT, and clearly understanding the strengths and limitations of established and emerging techniques of pediatric lung MRI can allow practitioners to select and combine the optimal techniques, apply them in clinical practice, and potentially improve early diagnostic accuracy and patient management.

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.

Overview of the ChILD Research Network: A roadmap for progress and success in defining rare diseases

Children's interstitial and diffuse lung diseases are a diverse group of rare lung disorders that present in childhood with diffuse pulmonary infiltrates and respiratory signs and symptoms. Children with these disorders face high morbidity and mortality and their families must cope with overwhelming uncertainty. Physicians caring for these patients are challenged by a paucity of directed therapies, or even understanding of natural history. Through the establishment of the Children's Interstitial Lung Disease Foundation Research Network and the Children's Interstitial Lung Disease Foundation significant progress has been made through collaboration and research. This review outlines the past and current successes in the new and rapidly growing field of Children's Interstitial and Diffuse Lung Disease.

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.

Pulmonary Aptamer Signatures in Children's Interstitial and Diffuse Lung Disease

Rationale: Biomarker signatures are needed in children with children's interstitial and diffuse lung disease (chILD) to improve diagnostic approaches, increase our understanding of disease pathogenesis, monitor disease progression, and develop new treatment strategies. Proteomic technology using SOMAmer (Slow Off-rate Modified Aptamer) nucleic acid-based protein-binding reagents allows for biomarker discovery.Objectives: We hypothesized that proteins and protein pathways in BAL fluid (BALF) would distinguish children with neuroendocrine cell hyperplasia of infancy (NEHI), surfactant dysfunction mutations, and other chILD diagnoses and control subjects.Methods: BALF was collected for clinical indications and banked in patients with chILD and disease control subjects using standardized protocols over 10 years. BALF supernatant was analyzed using an aptamer assay to measure 1,129 protein levels. Protein levels were compared between groups using an ANOVA and adjusted for multiple comparisons using false discovery rate. Proteins were classified into pathways. Hierarchical clustering was used to define endotypes in the group of children with NEHI.Measurements and Main Results: After correcting for multiple testing, children with NEHI (n = 22) had 202 aptamers that were significantly different (P < 0.05) in BALF compared with control subjects (n = 9). Children with surfactant mutation (n = 8) had 51 aptamers significantly different (P < 0.05) in BALF compared with control subjects (n = 9). Proteins associated with pulmonary fibrosis and inflammation were associated with the surfactant dysfunction group but not the NEHI group. Using hierarchical clustering analysis, two distinct NEHI endotypes were identified.Conclusions: Distinct proteins and protein pathways can be determined from BALF of children with chILD, and these hold promise to further our understanding of chILD.

One-year outcomes in a multicentre cohort study of incident rare diffuse parenchymal lung disease in children (ChILD)

We performed a prospective, observational, cohort study of children newly diagnosed with children's interstitial lung disease (ChILD), with structured follow-up at 4, 8, 12 weeks and 6 and 12 months. 127 children, median age 0.9 (IQR 0.3-7.9) years had dyspnoea (68%, 69/102), tachypnoea (75%, 77/103) and low oxygen saturation (SpO₂) median 92% (IQR 88-96). Death (n=20, 16%) was the most common in those <6 months of age with SpO₂<94% and developmental/surfactant disorders. We report for the first time that ChILD survivors improved multiple clinical parameters within 8-12 weeks of diagnosis. These data can inform family discussions and support clinical trial measurements.

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.

Lung and airway shape in neuroendocrine cell hyperplasia of infancy

BACKGROUND

Neuroendocrine cell hyperplasia of infancy (NEHI) is a rare lung disease associated with significant air trapping. Although chest CT is crucial in establishing a diagnosis, CT and biopsy findings do not reveal airway abnormalities to explain the air trapping.

OBJECTIVE

We compared lung and airway morphology obtained from chest CT scans in children with NEHI and control children. In the children with NEHI, we explored relationships between lung and airway shape and lung function.

MATERIALS AND METHODS

We performed a retrospective review of children with NEHI who underwent clinical chest CT. We identified control children of similar size and age. We created lung masks and airway skeletons using semi-automated software and compared them using statistical shape modeling methods. Then we calculated a logistic regression model using lung and airway shape to differentiate NEHI from controls, and we compared shape model parameters to lung function measurements.

RESULTS

Airway and lung shapes were statistically different between children with NEHI and controls. We noted a broad lung apex in the children with NEHI and a significantly increased apical anterior-posterior lung diameter. A logistic regression model including lung shape was 90% accurate in differentiating children with NEHI from controls. Correlation coefficients were significant between lung function values and lung and airway shape.

CONCLUSION

Lung and airway shapes were different between children with NEHI and control children in this cohort. Children with NEHI had an increased anteroposterior diameter of their lungs that might be useful in the diagnostic criteria.

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.

High-resolution CT findings of pulmonary interstitial glycogenosis

BACKGROUND

Pulmonary interstitial glycogenosis is a form of childhood interstitial lung disease characterized by the histological finding of abundant glycogen-laden mesenchymal cells within the pulmonary interstitium. Patients present in the neonatal period with disproportionate respiratory distress. Often, pulmonary interstitial glycogenosis is accompanied by alveolar simplification complicating recognition and diagnosis. Despite the recognition of pulmonary interstitial glycogenosis as a distinct entity, only a few case reports describing imaging findings are found in the literature, with no published systematic review available.

OBJECTIVE

The purpose of this review is to provide a review of CT findings of pulmonary interstitial glycogenosis with histological correlation to aid in early diagnosis and management.

MATERIALS AND METHODS

A 10-year retrospective review was performed to identify pediatric patients <18 years who underwent biopsy and CT within the last 10 years at our institution. The inclusion criteria include patients who had a CT within 3 months of biopsy and pathology-proven pulmonary interstitial glycogenosis CTs that were evaluated by three radiologists using a standardized scoring system.

RESULTS

Fifteen patients met inclusion criteria (9 male, 6 female). At the time of initial pre-biopsy CT, ages ranged from 2 weeks to 5 months. Pulmonary symptoms presented at birth in the majority of patients (n=13). Two patients presented in early infancy at 3 months (n=1) and 5 months (n=1). Ground glass opacities were the most common CT finding (n=14), which varied from diffuse to scattered. Cystic lucencies (n=11) were noted in the majority of patients as well. Interlobular septal thickening (n=10) and architectural distortion (n=8) were less common findings.

CONCLUSION

The most common CT findings of pulmonary interstitial glycogenosis are ground glass opacities with cystic lucencies. While the imaging findings are distinct from the typical presentation of neuroendocrine hyperplasia of infancy, there is significant overlap of these findings with surfactant dysfunction mutations, entities that also present with respiratory distress in the neonatal period. Therefore, imaging findings in pulmonary interstitial glycogenosis are helpful in guiding the need for genetic testing and/or biopsy.

Recurrent diffuse lung disease due to surfactant protein C deficiency

Surfactant protein C (SP-C) deficiency causes diffuse lung disease with variable prognosis and severity that usually presents in infancy. We present the case of a patient with diffuse lung disease who was successfully treated with hydroxychloroquine and steroids in infancy, who presented again as a young adult with respiratory symptoms. Exome sequencing identified a novel de novo SFTPC mutation (c.397A > C p.S133R). Mutated SP-C accumulates and leads to injury of alveolar type II cells, which normally replenish alveolar type I cells after injury. This may explain the symptom recurrence after lung injury in young adulthood. Although hydroxychloroquine has been hypothesized to interfere with mutated SP-C accumulation, data on long term outcome remains limited.

Role of High-Resolution Chest Computed Tomography in a Child with Persistent Tachypnoea and Intercostal Retractions: A Case Report of Neuroendocrine Cell Hyperplasia

Background: Chronic interstitial lung diseases in children (chILD) are a heterogeneous group of disorders that can represent a clinical challenge for pediatric pneumologists. Among them, neuroendocrine cell hyperplasia of infancy (NEHI) is a diffuse lung disease prevalent in the first years of life that spontaneously improves over time. The clinical presentation of NEHI is indistinguishable from other interstitial lung diseases, so a correct and non-invasive diagnosis by chest computed tomography (CT) without lung biopsy might not be simple. Case presentation: An 8-month-old male infant presented with a history of chronic tachypnoea and dyspnoea since 6 months of age. The patient was born at term, with APGAR scores of 9 and 10 at 1 and 5 min, respectively. Since his second month of life, the patient suffered from abnormal breathing, which was characterized by mild tachypnoea and costal retractions that worsened during breastfeeding, crying, and respiratory infections. Bilateral inspiratory crackles, preferential to the lung bases, without oxygen desaturation were detected. A chest X-ray showed a diffuse over-inflation of the lungs, but laboratory tests did not reveal any abnormalities. High-resolution chest CT documented patchy areas of ground-glass opacity involving the right upper lobe, middle lobe, and lingula, and showed mosaic areas of air-trapping, suggesting a diagnosis of NEHI. The infant was discharged without therapy and gradually improved over time. At 1 year of age, the patient was eupnoeic and chest auscultation had normalized. Conclusions: NEHI is an interstitial disease of infancy characterized by tachypnoea from the first months of life, with a good prognosis and for which a rational diagnostic approach is crucial for making a specific, early diagnosis. Initially, clinical suspicions can be confirmed with reasonable accuracy by a CT scan of the chest. Other more invasive and more expensive investigations should be reserved for selected cases that do not show a spontaneous, favourable clinical evolution.

All the "RAGE" in lung disease: The receptor for advanced glycation endproducts (RAGE) is a major mediator of pulmonary inflammatory responses

The receptor for advanced glycation endproducts (RAGE) is a pro-inflammatory pattern recognition receptor (PRR) that has been implicated in the pathogenesis of numerous inflammatory diseases. It was discovered in 1992 on endothelial cells and was named for its ability to bind advanced glycation endproducts and promote vascular inflammation in the vessels of patients with diabetes. Further studies revealed that RAGE is most highly expressed in lung tissue and spurred numerous explorations into RAGE's role in the lung. These studies have found that RAGE is an important mediator in allergic airway inflammation (AAI) and asthma, pulmonary fibrosis, lung cancer, chronic obstructive pulmonary disease (COPD), acute lung injury, pneumonia, cystic fibrosis, and bronchopulmonary dysplasia. RAGE has not yet been targeted in the lungs of paediatric or adult clinical populations, but the development of new ways to inhibit RAGE is setting the stage for the emergence of novel therapeutic agents for patients suffering from these pulmonary conditions.

Pulmonary hypertension in childhood interstitial lung disease: A systematic review of the literature

Childhood interstitial lung disease (chILD) comprises a wide heterogeneous group of rare parenchymal lung disorders associated with substantial morbidity and mortality. Pulmonary hypertension is a common comorbidity in adults with interstitial lung disease (ILD) and associated with poor survival. We aimed to systematically review the literature regarding the occurrence of pulmonary hypertension (PH) in chILD, its effect on prognosis and healthcare use, and its treatment in clinical practice. Searches of PubMed and EMBASE databases (up to February 2016), and American Thoracic Society conference abstracts (2009-2015) were conducted using relevant keywords. References from selected articles and review papers were scanned to identify further relevant articles. A total of 20 articles were included; estimates of PH in chILD ranged from 1% to 64% with estimates among specific chILD entities ranging from 0% to 43%. Comparisons between studies were limited by differences in the study populations, including the size, age range, and heterogeneous composition of the ILD case series in terms of the nature and severity of the clinical entities, and also the methods used to diagnose PH. Three studies found that among patients with chILD, those with PH had a significantly higher risk (up to sevenfold) of death compared with those without PH. Information on the treatment of pulmonary hypertension in chILD or the effect of PH on healthcare use was not available. Data on the use and effectiveness of treatments for pulmonary hypertension in chILD are required to address this area of unmet need. Pediatr Pulmonol. 2017;52:689-698. © 2016 Wiley Periodicals, Inc.

Molecular mechanisms underlying fibrosis and elastin destruction in childhood interstitial lung diseases

OBJECTIVE

This study aimed to evaluate fibrosis and elastin destruction in childhood interstitial lung disease (chILD) patients.

METHODS

Sixty patients and twenty healthy children were recruited. On admission, evaluation of chILD severity was made using Fan chILD score. Participants provided urine and blood samples. Plasma levels of transforming growth factor (TGF)-β₁, connective tissue growth factor (CCN2), soluble factor related apoptosis (sFas) and long non-coding RNAs and urinary levels of desmosine/urinary creatinine (UDes/UCr) were measured.

RESULTS

In patients, clinical findings were crackles (100.00%), tachypnea (65.00%), cardiomegaly (45.00%), digital clubbing (43.30%), cough (33.00%), cyanosis (26.70%), hepatomegaly (28.30%) and wheezes (23.30%). Categorizing of the patients with Fan chILD clinical score revealed that most patients 33.30% scored (3, symptomatic with abnormal saturation/cyanosis during exercise) then 28.30% scored (5, symptomatic with clinical and echocardiographic features of pulmonary hypertension), 18.30% scored (2, symptomatic with normal room air saturations), 15.00% scored (1, asymptomatic) and 5.00% scored (4, symptomatic with abnormal room air saturation/cyanosis at rest). TGF-β₁, CCN2, sFas, lncrRNA-2700086A05Rik relative gene expression and UDes/UCr levels were higher in patients than controls (P=0.002, P=0.001, P=0.001, P=0.001, P=0.001, respectively). In patients, significant positive correlations were found between TGF-β₁ and CCN2, sFas, UDes/UCr; between CCN2 and both sFas and UDes/UCr; between UDes/UCr and sFas. Morbidity and mortality rates were 46.70% and 10.00%, respectively.

CONCLUSION

Markers of fibrosis (TGF-β₁, sFas, CCN2) and elastin destruction (UDes/UCr) were increased in chILD especially in patients with long disease duration. So blockage of their pathways signals may offer novel therapeutic targets.

Clinical, cytological and microbiological evaluation of bronchoalveolar lavage in children: A referral hospital-based study

INTRODUCTION

Diffuse lung diseases (DLD) in children involve a group of heterogeneous, rare disorders. In spite of the low diagnostic yield in pediatric DLD, bronchoalveolar lavage (BAL) can be used to diagnose specific disorders. There are few studies about microbial and cellular profiles of BAL samples in these patients. This study was conducted to evaluate the clinical, cytological and microbiological evaluation of BAL in children with DLD.

METHODS

The clinical, cytological and microbiological profiles of BAL samples of all patients with DLD who underwent the fiberoptic bronchoscopy (FOB) at Children's Medical Center, an Iranian referral pediatrics Hospital during a year were evaluated.

RESULTS

In 18 patients (18.4%) of the 98 cases studied, 22 pathogens were obtained as etiologic agents. The mean total cells count of BAL was 23.9 × 104 ± 12.9 × 104/ml. The mean percentages of cellular components were macrophages (70.2%), neutrophils (16.3%), lymphocytes (11.8%) and eosinophils (1.4%), respectively. The type of lung disease was significantly associated with the mean percentage of lymphocytes (p = 0.005) and the percentage of neutrophils (p = 0.042).

CONCLUSION

FOB and BAL evaluation in combination with clinical and radiographic imaging data may be helpful for identifying of presumptive diagnosis of DLD in children.

Interstitial Lung Disease in Children Younger Than 2 Years

Childhood interstitial lung disease (chILD) represents a highly heterogeneous group of rare disorders associated with substantial morbidity and mortality. Although our understanding of chILD remains limited, important advances have recently been made, the most important being probably the appreciation that disorders that present in early life are distinct from those occurring in older children and adults, albeit with some overlap. chILD manifests with diffuse pulmonary infiltrates and nonspecific respiratory signs and symptoms, making exclusion of common conditions presenting in a similar fashion an essential preliminary step. Subsequently, a systematic approach to diagnosis includes a careful history and physical examination, computed tomography of the chest, and some or all of bronchoscopy with bronchoalveolar lavage, genetic testing, and if diagnostic uncertainty persists, lung biopsy. This review focuses on chILD presenting in infants younger than 2 years of age and discusses recent advances in the classification, diagnostic approach, and management of chILD in this age range. We describe novel genetic entities, along with initiatives that aim at collecting clinical data and biologic samples from carefully characterized patients in a prospective and standardized fashion. Early referral to expert centers and timely diagnosis may have important implications for patient management and prognosis, but effective therapies are often lacking. Following massive efforts, international collaborations among the key stakeholders are finally starting to be in place. These have allowed the setting up and conducting of the first randomized controlled trial of therapeutic interventions in patients with chILD.

Pulmonary Involvement in Niemann-Pick Disease: A State-of-the-Art Review

Niemann-Pick disease is a rare autosomal recessive lysosomal storage disease with three subtypes. Types A and B result from a deficiency of acid sphingomyelinase activity, associated with the accumulation of lipid-laden macrophages (so-called Niemann-Pick cells) in various tissues, especially the liver and spleen. Type A is a fatal neurodegenerative disorder of infancy. Type B Niemann-Pick disease is a less severe form with milder neurological involvement, characterized by hepatosplenomegaly, hyperlipidemia, and pulmonary involvement; most patients live into adulthood. Type C Niemann-Pick disease is a complex lipid storage disorder caused by defects in cholesterol trafficking, resulting in a clinical presentation dominated by neurological involvement. Pulmonary involvement occurs in all three types of Niemann-Pick disease, but most frequently in type B. Respiratory manifestations range from a lack of symptoms to respiratory failure. Progression of respiratory disease is slow, but inexorable, due to the accumulation of Niemann-Pick cells in the alveolar septa, bronchial walls, and pleura, potentially leading to a progressively worsening restrictive pattern on pulmonary function testing. Bronchoalveolar lavage has important diagnostic value because it shows the presence of characteristic Niemann-Pick cells. Radiographic findings consist of a reticular or reticulonodular pattern and, eventually, honeycombing, involving mainly the lower lung zones. The most common changes identified by high-resolution computed tomography are ground-glass opacities, mild smooth interlobular septal thickening, and intralobular lines. The aim of this review is to describe the main clinical, imaging, and pathological aspects of Niemann-Pick disease, with a focus on pulmonary involvement.

The First Successful Heart-Lung Transplant in a Korean Child with Humidifier Disinfectant-Associated Interstitial Lung Disease

From 2006 to 2011, an outbreak of a particular type of childhood interstitial lung disease occurred in Korea. The condition was intractable and progressed to severe respiratory failure, with a high mortality rate. Moreover, in several familial cases, the disease affected young women and children simultaneously. Epidemiologic, animal, and post-interventional studies identified the cause as inhalation of humidifier disinfectants. Here, we report a 4-year-old girl who suffered from severe progressive respiratory failure. She could survive by 100 days of extracorporeal membrane oxygenation support and finally, underwent heart-lung transplantation. This is the first successful pediatric heart-lung transplantation carried out in Korea.

Recent advances in paediatric respiratory medicine

This review highlights important advances in paediatric respiratory medicine since 2014, excluding cystic fibrosis. It focuses mainly on the more common conditions, bronchopulmonary dysplasia, bronchiolitis and preschool wheezing, asthma, pneumonia and sleep, and highlights some of the rarer conditions such as primary ciliary dyskinesia and interstitial lung disease (ILD).

Interstitial Lung Disease in Childhood: Clinical and Genetic Aspects

Interstitial lung disease (ILD) in childhood is a heterogeneous group of rare pulmonary conditions presenting chronic respiratory disorders. Many clinical features of ILD still remain unclear, making the treatment strategies mainly investigative. Guidelines may provide physicians with an overview on the diagnosis and therapeutic directions. However, the criteria used in different clinical studies for the classification and diagnosis of ILDs are not always the same, making the development of guidelines difficult. Advances in genetic testing have thrown light on some etiologies of ILD, which were formerly classified as ILDs of unknown origins. The need of genetic testing for unexplained ILD is growing, and new classification criteria based on the etiology should be adopted to better understand the disease. The purpose of this review is to give an overview of the clinical and genetic aspects of ILD in children.

The Respiratory System

This chapter addresses upper airway physiology for the pediatric intensivist, focusing on functions that affect ventilation, with an emphasis on laryngeal physiology and control in breathing. Effective control of breathing ensures that the airway is protected, maintains volume homeostasis, and provides ventilation. Upper airway structures are effectors for all of these functions that affect the entire airway. Nasal functions include air conditioning and protective reflexes that can be exaggerated and involve circulatory changes. Oral cavity and pharyngeal patency enable airflow and feeding, but during sleep pharyngeal closure can result in apnea. Coordination of breathing with sucking and nutritive swallowing alters during development, while nonnutritive swallowing at all ages limits aspiration. Laryngeal functions in breathing include protection of the subglottic airway, active maintenance of its absolute volume, and control of tidal flow patterns. These are vital functions for normal lung growth in fetal life and during rapid adaptations to breathing challenges from birth through adulthood. Active central control of breathing focuses on the coordination of laryngeal and diaphragmatic activities, which adapts according to the integration of central and peripheral inputs. For the intensivist, knowledge of upper airway physiology can be applied to improve respiratory support. In a second part the mechanical properties of the respiratory system as a critical component of the chain of events that result in translation of the output of the respiratory rhythm generator to ventilation are described. A comprehensive understanding of respiratory mechanics is essential to the delivery of optimized and individualized mechanical ventilation. The basic elements of respiratory mechanics will be described and developmental changes in the airways, lungs, and chest wall that impact on measurement of respiratory mechanics with advancing postnatal age are reviewed. This will be follwowed by two sections, the first on respiratory mechanics in various neonatal pathologies and the second in pediatric pathologies. The latter can be classified in three categories. First, restrictive diseases may be of pulmonary origin, such as chronic interstitial lung diseases or acute lung injury/acute respiratory distress syndrome, which are usually associated with reduced lung compliance. Restrictive diseases may also be due to chest wall abnormalities such as obesity or scoliosis (idiopathic or secondary to neuromuscular diseases), which are associated with a reduction in chest wall compliance. Second, obstructive diseases are represented by asthma and wheezing disorders, cystic fibrosis, long term sequelae of neonatal lung disease and bronchiolitis obliterans following hematopoietic stem cell transplantation. Obstructive diseases are defined by a reduced FEV1/VC ratio. Third, neuromuscular diseases, mainly represented by DMD and SMA, are associated with a decrease in vital capacity linked to respiratory muscle weakness that is better detected by PImax, PEmax and SNIP measurements.

Natural history of five children with surfactant protein C mutations and interstitial lung disease

Interstitial lung diseases in infants and children are uncommon and may be caused by specific inborn errors of surfactant metabolism. Five children with open lung biopsy diagnosed interstitial lung disease were followed (mean of 27.2 years) and evaluated for surfactant protein gene mutations. Four of the children were originally diagnosed as desquamative interstitial pneumonitis and one as chronic interstitial pneumonitis. All had good response to chloroquine or hydroxychloroquine treatment for periods of 7-38 months. Lung function tests, incremental exercise tests, and rentgenological studies were performed in the children. Surfactant protein gene mutations were searched in all the patients and in part of their families. Three of the patients, aged now 32, 29, and 37 years, feel well and have normal lung function, while two of the patients, both females, aged 28 and 37 years, conduct normal activities of daily living, have healthy children but have clinical, physiological and rentgenological evidence of restrictive lung disease. All five patients were found to have surfactant protein C gene (SFTPC) mutations, three of them with the most common mutation (p.I73T) and the other two with new mutations of surfactant protein C gene (p.I38F and p.V39L). We conclude that detection of surfactant protein mutations should be attempted in all children presenting with interstitial lung disease. Furthermore, treatment with hydroxychloroquine should be considered in children with SFTPC mutations. Prospective evaluation of hydroxychloroquine therapy in a greater number of patients is needed.

Diagnostic criteria and follow-up in neuroendocrine cell hyperplasia of infancy: a case series

OBJECTIVE

Neuroendocrine cell hyperplasia of infancy (NEHI) is a form of childhood interstitial lung disease characterized by tachypnea, retractions, crackles, and hypoxia. The aim of this study was to report and discuss the clinical, imaging, and histopathological findings in a series of NEHI cases at a tertiary pediatric hospital, with an emphasis on diagnostic criteria and clinical outcomes.

METHODS

Between 2003 and 2011, 12 full-term infants were diagnosed with NEHI, based on clinical and tomographic findings. Those infants were followed for 1-91 months. Four infants were biopsied, and the histopathological specimens were stained with bombesin antibody.

RESULTS

In this case series, symptoms appeared at birth in 6 infants and by 3 months of age in the remaining 6. In all of the cases, NEHI was associated with acute respiratory infection. The most common initial chest HRCT findings were ground-glass opacities that were in the middle lobe/lingula in 12 patients and in other medullary areas in 10. Air trapping was the second most common finding, being observed in 7 patients. Follow-up HRCT scans (performed in 10 patients) revealed normal results in 1 patient and improvement in 9. The biopsy findings were nonspecific, and the staining was positive for bombesin in all samples. Confirmation of NEHI was primarily based on clinical and tomographic findings. Symptoms improved during the follow-up period (mean, 41 months). A clinical cure was achieved in 4 patients.

CONCLUSIONS

In this sample of patients, the diagnosis of NEHI was made on the basis of the clinical and tomographic findings, independent of the lung biopsy results. Most of the patients showed clinical improvement and persistent tomographic changes during the follow-up period, regardless of the initial severity of the disease or type of treatment.

Lung biopsy for chronic pulmonary disease in children

INTRODUCTION AND OBJECTIVES

Lung biopsy is frequently used in the management of children with chronic pulmonary disease to obtain a histological diagnosis. We further evaluate the role of lung biopsy by reviewing our experience of this procedure.

METHODS

A retrospective case-note review was carried out of all patients in our regional service under 16 years who underwent a lung biopsy from 1998 to 2011.

RESULTS

Thirty-three children (12 boys) (median 5 years 5 months, range 2 months to 16 years) underwent lung biopsy in the period studied. Following the procedure, 17 patients required ventilation on the intensive care unit for a median of two days (range 1-56 days). Complication rate was 30% (10/33); seven simple pneumothoraces, one tension pneumothorax, and one pneumonia (one child experienced more than one complication). The operative mortality was 12% (4/33). Three children (9%) died within 28 days of surgery. Twenty-six (79%) biopsies provided a definitive histological diagnosis. In 16 (48%) children, the working diagnosis and treatment were changed following lung biopsy.

CONCLUSION

Lung biopsy has an important role in the management of children with chronic pulmonary disease. However, it carries significant risks which must be considered when assessing the need for histological diagnosis.

Interstitial lung disease in children

PURPOSE OF REVIEW

There has been tremendous progress in the approach to childhood interstitial lung diseases (chILD), with particular recognition that interstitial lung disease (ILD) in infants is often distinct from the forms that occur in older children and adults. Diagnosis is challenging because of the rarity of ILD and the fact that the presenting symptoms of ILD often overlap those of common respiratory disorders. This review summarizes the newly published recommendations for diagnosis and management, and highlights the recent scientific advances in several specific forms of chILD.

RECENT FINDINGS

Clinical practice guidelines emphasize the role for chest computed tomography, genetic testing, and lung biopsy in the diagnostic evaluation of children with suspected ILD. Recent studies have better defined the characteristics and molecular understanding of several different forms of ILD, including neuroendocrine cell hyperplasia of infancy and ILD, due to mutations in genes affecting surfactant production and metabolism. Despite significant progress, definitive therapies are often lacking.

SUMMARY

chILD encompasses a collection of rare, diffuse lung diseases. Timely recognition of children with suspected ILD and initiation of appropriate diagnostic evaluations will facilitate medical management. Systematic approaches to clinical care and further studies are needed to improve the outcomes of children with these rare disorders.

Diffuse Lung Disease

Diffuse lung disease (DLD) comprises a diverse group of disorders characterized by widespread pulmonary parenchymal pathology and impaired gas exchange. While many of these disorders are categorized under the rubric of interstitial lung disease (ILD), some of these disorders involve the airspaces or peripheral airways in addition to, or rather than, the interstitium. Some of these disorders are present primarily in infancy or early childhood, while others that are prevalent in adulthood rarely occur in childhood. This chapter will review the classification of pediatric DLD and the characteristic imaging findings of specific disorders to facilitate accurate diagnosis and guide appropriate treatment of children with these disorders.

Bronchoalveolar lavage fluid cytokine profiles in neuroendocrine cell hyperplasia of infancy and follicular bronchiolitis

Background

Neuroendocrine Cell Hyperplasia of Infancy (NEHI) and Follicular Bronchiolitis (FB) are rare pediatric diffuse lung diseases with poorly understood pathogenesis and similar clinical presentations. We sought to determine if cellular and cytokine profiles in bronchoalveolar lavage fluid (BALF) from subjects with NEHI and FB would differ from pediatric disease controls.

Methods

BALF was obtained from forty-one subjects classified into four disease groups: NEHI, Cystic Fibrosis (CF), other airway disease controls (DC), and FB during clinically indicated procedures. BALF cellular profiles and ten cytokines were measured and values compared across groups using descriptive and nonparametric statistics.

Results

Significant BALF cellular and cytokine differences were seen across all groups. NEHI subjects exhibited the lowest total absolute white blood cell (WBC) levels with a higher percentage of BALF alveolar macrophages compared to controls. NEHI also had lower levels of IL-1β, MIP-1β and IL-8 and FB had higher levels of IL-1ra, G-CSF and VEGF compared to all groups. IL-6 was elevated in CF and FB.

Conclusions

BALF cytokine and cellular profiles differed between NEHI, FB, CF and DC subjects. This pilot data suggests different and distinguishing inflammatory responses in the airway, with the least inflammatory being NEHI. These data could have diagnostic implications.

Childhood interstitial lung diseases: an 18-year retrospective analysis

OBJECTIVE

Childhood interstitial lung diseases (ILD) occur in a variety of clinical contexts. Advances in the understanding of disease pathogenesis and use of standardized terminology have facilitated increased case ascertainment. However, as all studies have been performed at specialized referral centers, the applicability of these findings to general pulmonary practice has been uncertain. The objective of this study was to determine the historical occurrence of childhood ILD to provide information reflecting general pediatric pulmonary practice patterns.

METHODS

Childhood ILD cases seen at Vanderbilt Children's Hospital from 1994 to 2011 were retrospectively reviewed and classified according to the current pediatric diffuse lung disease histopathologic classification system.

RESULTS

A total of 93 cases were identified, of which 91.4% were classifiable. A total of 68.8% (64/93) of subjects underwent lung biopsy in their evaluations. The largest classification categories were disorders related to systemic disease processes (24.7%), disorders of the immunocompromised host (24.7%), and disorders more prevalent in infancy (22.6%). Eight cases of neuroendocrine cell hyperplasia of infancy (NEHI) were identified, including 5 that were previously unrecognized before this review.

CONCLUSIONS

Our findings demonstrate the general scope of childhood ILD and that these cases present within a variety of pediatric subspecialties. Retrospective review was valuable in recognizing more recently described forms of childhood ILD. As a significant portion of cases were classifiable based on clinical, genetic, and/or radiographic criteria, we urge greater consideration to noninvasive diagnostic approaches and suggest modification to the current childhood ILD classification scheme to accommodate the increasing number of cases diagnosed without lung biopsy.

Contemporary topics in pediatric pulmonology for the primary care clinician

Disorders of the respiratory system are commonly encountered in the primary care setting. The presentations are myriad and this review will discuss some of the more intriguing or vexing disorders that the clinician must evaluate and treat. Among these are dyspnea, chronic cough, chest pain, wheezing, and asthma. Dyspnea and chest pain have a spectrum ranging from benign to serious, and the ability to effectively form a differential diagnosis is critical for reassurance and treatment, along with decisions on when to refer for specialist evaluation. Chronic cough is one of the more common reasons for primary care office visits, and once again, a proper differential diagnosis is necessary to assist the clinician in formulating an appropriate treatment plan. Infant wheezing creates much anxiety for parents and accounts for a large number of office visits and hospital admissions. Common diagnoses and evaluation strategies of early childhood wheezing are reviewed. Asthma is one of the most common chronic diseases of children and adults. The epidemiology, diagnosis, evaluation, treatment, and the patient/parent education process will be reviewed. A relatively new topic for primary care clinicians is cystic fibrosis newborn screening. The rationale, methods, outcomes, and implications will be reviewed. This screening program may present some challenges for clinicians caring for newborns, and an understanding of the screening process will help the clinician communicate effectively with parents of the patient.

Lung transplantation for childhood diffuse lung disease

BACKGROUND

Pediatric diffuse lung diseases comprise a heterogeneous group of rare lung disorders which may lead to end stage lung disease and referral for lung transplantation. Previous studies are limited by small numbers of patients with specific forms of diffuse lung disease. Children with all forms of diffuse lung disease who underwent lung transplantation at two pediatric centers were evaluated in terms of several pre- and post-transplant factors and compared to children with other end stage lung disorders.

METHODS

A retrospective chart review was performed on all patients transplanted between October 1, 2002 and June 15, 2007 at Texas Children's Hospital and St. Louis Children's Hospital. Multiple pre-transplant characteristics and post-transplant morbidities and mortality were compared between diffuse lung disease, cystic fibrosis, and pulmonary vascular disease groups.

RESULTS

There were 31 diffuse lung disease (DLD), 57 cystic fibrosis (CF), and 16 pulmonary vascular disease (PVD) patients included in our analysis. Patients with DLD had significantly higher pre-transplant morbidity including lower percent predicted of forced expiratory volume in first second (P = 0.013) and more patients with pulmonary hypertension (P = 0.001) and hypercapnia (P = 0.031). Compared to CF patients, more DLD and PVD patients required invasive ventilation (P = 0.001) and care in the pediatric intensive care unit (P = 0.001). After transplant, there was a difference among the three groups with regards to number of acute allograft rejections but statistical limitations preclude knowing between which group the difference lies. A difference in time to bronchiolitis obliterans was found between the PVD and CF groups but not when compared to the DLD patients. The three groups had similar time to post-transplant lymphoproliferative disease, rate of infections, and survival.

CONCLUSION

Lung transplantation is as successful for patients with end stage diffuse lung disease as compared to other lung transplant candidates.