Evaluation of a diagnostic approach to pediatric interstitial lung disease

Fibrosing Interstitial Lung Disease in Children: An HRCT-Based Analysis

OBJECTIVE

To determine high resolution CT (HRCT) patterns of pulmonary fibrosis (PF) in children; and their etiological correlates.

METHODS

This was a retrospective study involving 149 children with diffuse lung disease (DLD). Patterns of involvement were classified based on dominant lung finding as ground glass opacity (GGO) dominant, nodule dominant, cystic lung disease, or PF. Patterns of PF were classified based on distribution and morphology into airway centric fibrosis (ACF), subpleural fibrosis (SPF), progressive massive fibrosis (PMF) and fibrocavitary. A comparison was made between the two dominant groups for apicobasal distribution, associated findings (GGO, nodules, cysts), and pulmonary artery hypertension (PAH).

RESULTS

Nineteen patients showed PF on HRCT. ACF was commonest (52.6%), followed by SPF (42.1%). The common etiology was sarcoidosis (30%) in ACF, and connective tissue disorders (CTD) (50%) in SPF. Significant difference was found between ACF and SPF in apicobasal distribution (p = 0.04), presence of nodules (p = 0.03), and cysts (p = 0.02).

CONCLUSION

PF may present as an end stage of several childhood lung diseases. PF on imaging has discernible morphological patterns that correlate with underlying etiology.

Environmental hazards and demographic and clinical data of childhood interstitial lung diseases in a tertiary institute in Egypt

Background

The incidence of childhood interstitial lung diseases increased in the last years in Egypt. Changes in environmental and climatic conditions may be contributing factors. Also, raising birds at home increased in the past years due to financial issues. Other environmental factors include increased industries, traffic, and pollution. Our study aimed to assess the environmental hazards and the severity of childhood interstitial lung diseases.

Results

Sixty-five percent of patients with childhood interstitial lung diseases (chILD) were exposed to cigarette smoke; 45% were exposed to birds, 30% to industrial wastes, 20% to grass and pesticides, and 10% to animals.

Conclusions

Exposure to cigarette smoke and birds increases the risk of development of chILD.

Lung biopsy in children's interstitial and diffuse lung disease: Does it alter management?

INTRODUCTION

Pediatric patients with acute life-threatening consequences of interstitial and diffuse lung disease are often treated with empiric systemic corticosteroids, immune modulators, and/or broad antibiotic therapy. Histological evaluation of lung tissue represents the final necessary step in diagnosis-however, a definitive diagnosis may still remain elusive and medical therapies may not be changed following biopsy. We hypothesized that lung biopsy from pediatric patients with children's interstitial and diffuse lung disease (chILD) without a defined lesion on computed tomography (CT) imaging would guide diagnosis, but not substantially alter clinical management.

METHODS

After IRB approval, patients who underwent a lung biopsy at a single large children's hospital between 2013 and 2018 were retrospectively reviewed. Patients without a defined lesion were included. Demographics, length of stay, oxygen-requirements, steroid, unique number of immune modulators, and antibiotics prebiopsy and postbiopsy were reviewed. Nonparametric data were compared by the Mann Whitney U and Kruskal Wallace tests and expressed as median with interquartile range. Decision tree alterations were analyzed by t test. P < .05 was significant.

RESULTS

Sixty-four patients underwent lung biopsy during the period. Nineteen (30%) did not have a defined lesion on CT scan, and were included. A significant difference was seen between prebiopsy, 2 weeks, and 2 months postbiopsy prednisone dosing (P = .03), while the number of unique immune modulators, antibiotics, type of oxygen support and FiO₂ were not significantly different before or after obtaining biopsy results. Pathology results provided additional information in 12 of 19 (63%) patients which resulted in management changes.

CONCLUSIONS

Lung biopsy in chILD may guide clinical management, especially influencing the management of steroid dosing. Although on aggregate the number of antibiotics, immune modulators, mode of oxygen support and FiO₂ did not differ significantly before and after biopsy, the pathologic evaluation provided diagnostic information that led to a variety of changes in therapeutic management in greater than half of the population.

Pediatric Interstitial (Diffuse) Lung Disease

Interstitial (diffuse) lung diseases in infants and children comprise a rare heterogeneous group of parenchymal lung disorders, with clinical syndromes characterized by dyspnea, tachypnea, crackles, and hypoxemia. They arise from a wide spectrum of developmental, genetic, inflammatory, infectious, and reactive disorders. In the past, there has been a paucity of information and limited understanding regarding their pathogenesis, natural history, imaging findings, and histopathologic features, which often resulted in enormous diagnostic challenges and confusion. In recent years, there has been a substantial improvement in the understanding of interstitial lung disease in pediatric patients due to the development of a structured classification system based on the etiology of the lung disease, established pathologic criteria for consistent diagnosis, and the improvement of thoracoscopic techniques for lung biopsy. Imaging plays an important role in evaluating interstitial lung diseases in infants and children by confirming and characterizing the disorder, generating differential diagnoses, and providing localization for lung biopsy for pathological diagnosis. In this chapter, the authors present the epidemiology, challenges, and uncertainties of diagnosis and amplify a recently developed classification system for interstitial lung disease in infants and children with clinical, imaging, and pathological correlation.

Utility of open surgical lung biopsy in children

INTRODUCTION

Open lung biopsy (OLB) is commonly used to obtain a definitive histological diagnosis in children with respiratory disorders. This allows correct treatment pathways to be followed and guides discussions surrounding prognosis. Our aim was to determine if OLB is useful in obtaining a conclusive diagnosis in a child with complex respiratory disease.

MATERIALS AND METHODS

In total, 179 OLB episodes were identified in children under 18 years from 2006 to 2016. Biopsies confirming congenital thoracic malformations or pulmonary metastatic disease were excluded.

RESULTS

42 patients had 44 episodes of OLB in the period studied. A definitive histological diagnosis was reached in 35 (79%) cases. There were no deaths directly attributable to OLB surgery.

CONCLUSION

OLB contributed substantially in obtaining a definitive diagnosis for our patient population, no increase in mortality. It allowed targeted treatment and provided valuable prognostic information on the likely progression of the disease so families could plan for palliation where appropriate.

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

BACKGROUND

Childhood interstitial lung disease (chILD) represents a rare heterogeneous group of respiratory disorders. In the absence of randomized controlled clinical trials, global collaborations have utilized case series with an aim to standardising approaches to diagnosis and management. Australasian data are lacking. The aim of this study was to calculate prevalence and report the experience of chILD in Australasia over a decade.

METHODS

Paediatric pulmonologists in Australia and New Zealand involved in the care of patients aged 0-18 years with chILD completed a questionnaire on demographics, clinical features and outcomes, over a 10 year period. These data, together with data from the 2 reference genetics laboratories, were used to calculate prevalence.

RESULTS

One hundred fifteen cases were identified equating to a period prevalence (range) of 1.5 (0.8-2.1) cases/million for children aged 0-18years. Clinical data were provided on 106 patients: the <2 year group comprised 66 children, median age (range) 0.50 years (0.01-1.92); the ≥2 year group comprised 40 children, median age 8.2 years (2.0-18.0). Management approach was heterogeneous. Overall, 79% of patients had a good clinical outcome. Mortality rate was 7% in the study population.

CONCLUSION

chILD is rare in Australasia. This study demonstrates variation in the investigations and management of chILD cases across Australasia, however the general outcome is favorable. Further international collaboration will help finesse the understanding of these disorders.

Diffuse Lung Disease in Biopsied Children 2 to 18 Years of Age. Application of the chILD Classification Scheme

RATIONALE

Children's Interstitial and Diffuse Lung Disease (chILD) is a heterogeneous group of disorders that is challenging to categorize. In previous study, a classification scheme was successfully applied to children 0 to 2 years of age who underwent lung biopsies for chILD. This classification scheme has not been evaluated in children 2 to 18 years of age.

OBJECTIVES

This multicenter interdisciplinary study sought to describe the spectrum of biopsy-proven chILD in North America and to apply a previously reported classification scheme in children 2 to 18 years of age. Mortality and risk factors for mortality were also assessed.

METHODS

Patients 2 to 18 years of age who underwent lung biopsies for diffuse lung disease from 12 North American institutions were included. Demographic and clinical data were collected and described. The lung biopsies were reviewed by pediatric lung pathologists with expertise in diffuse lung disease and were classified by the chILD classification scheme. Logistic regression was used to determine risk factors for mortality.

MEASUREMENTS AND MAIN RESULTS

A total of 191 cases were included in the final analysis. Number of biopsies varied by center (5-49 biopsies; mean, 15.8) and by age (2-18 yr; mean, 10.6 yr). The most common classification category in this cohort was Disorders of the Immunocompromised Host (40.8%), and the least common was Disorders of Infancy (4.7%). Immunocompromised patients suffered the highest mortality (52.8%). Additional associations with mortality included mechanical ventilation, worse clinical status at time of biopsy, tachypnea, hemoptysis, and crackles. Pulmonary hypertension was found to be a risk factor for mortality but only in the immunocompetent patients.

CONCLUSIONS

In patients 2 to 18 years of age who underwent lung biopsies for diffuse lung disease, there were far fewer diagnoses prevalent in infancy and more overlap with adult diagnoses. Immunocompromised patients with diffuse lung disease who underwent lung biopsies had less than 50% survival at time of last follow-up.

An official American Thoracic Society clinical practice guideline: classification, evaluation, and management of childhood interstitial lung disease in infancy

BACKGROUND

There is growing recognition and understanding of the entities that cause interstitial lung disease (ILD) in infants. These entities are distinct from those that cause ILD in older children and adults.

METHODS

A multidisciplinary panel was convened to develop evidence-based guidelines on the classification, diagnosis, and management of ILD in children, focusing on neonates and infants under 2 years of age. Recommendations were formulated using a systematic approach. Outcomes considered important included the accuracy of the diagnostic evaluation, complications of delayed or incorrect diagnosis, psychosocial complications affecting the patient's or family's quality of life, and death.

RESULTS

No controlled clinical trials were identified. Therefore, observational evidence and clinical experience informed judgments. These guidelines: (1) describe the clinical characteristics of neonates and infants (<2 yr of age) with diffuse lung disease (DLD); (2) list the common causes of DLD that should be eliminated during the evaluation of neonates and infants with DLD; (3) recommend methods for further clinical investigation of the remaining infants, who are regarded as having "childhood ILD syndrome"; (4) describe a new pathologic classification scheme of DLD in infants; (5) outline supportive and continuing care; and (6) suggest areas for future research.

CONCLUSIONS

After common causes of DLD are excluded, neonates and infants with childhood ILD syndrome should be evaluated by a knowledgeable subspecialist. The evaluation may include echocardiography, controlled ventilation high-resolution computed tomography, infant pulmonary function testing, bronchoscopy with bronchoalveolar lavage, genetic testing, and/or lung biopsy. Preventive care, family education, and support are essential.

Diffuse lung disease in infancy and childhood: expanding the chILD classification

AIMS

Diffuse parenchymal lung diseases (DPLD) in children comprise a wide spectrum of rare disorders. In 2007 the Children's Interstitial Lung Disease (chILD) Research Cooperative proposed a classification system for DPLD in children <2 years of age. The aims of our study were to determine the utility and reproducibility of this system in children <2 years of age, and test its extension to 18 years of age.

METHODS AND RESULTS

Of 211 cases, 93 were <2 years of age at presentation and 58% were included in the chILD classification. In 118 cases aged between 2 and 18 years there was a wider distribution of disorders, overlapping with those seen in adults, necessitating expansion of the chILD classification types to encompass all reviewed cases, in particular patients with 'adult' diffuse lung diseases. Many cases showed mixed histological patterns, overlap often being between groups of disorders more prevalent in infancy. Concordance between reporting pathologists was 90%.

CONCLUSIONS

The chILD scheme allows classification of conditions more common in children <2 years of age. It can be applied to children of any age, although additional entities need to be included. We propose a more histologically based system for use when assessing biopsies in this context.

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.

Clinical profile of interstitial lung disease in Indian children

OBJECTIVE

To describe the clinical spectrum and factors associated with poor short-term outcomes in children with interstitial lung disease (ILD).

DESIGN

Retrospective chart review

SETTING

Pediatric Chest Clinic of a tertiary care hospital

METHODOLOGY

We retrieved information regarding clinical course and laboratory features of all children diagnosed as ILD between January 1999 and February 2010. Disease severity was assessed using ILD score based on clinical features and SpO2 at the time of initial evaluation. Outcome was assessed after 3 months of initial diagnosis as improved or death/no improvement in symptoms.

RESULTS

90 children (median age, 6.8 years; 62% boys) were diagnosed to have ILD during this period. 46 children were classified as having definite ILD while 44 had possible ILD. The commonest clinical features at presentation were cough (82.2%), dyspnea (80%), pallor (50%), and crackles (45.6%). 3 children (3.3%) died while 21 (23%) showed no improvement in clinical status on follow-up at 3 months. A higher ILD score (RR 3.72, 95% CI 1.4, 9.9) and lower alkaline phosphatase levels (median [IQR]: 205 [175.2] vs. 360 [245.7]; P=0.006) were found to be significantly associated with worse outcomes.

CONCLUSION

The common clinical features of ILD in our study included breathlessness, cough and hypoxemia. A working diagnosis of ILD can be made with the help of imaging, bronchoscopy, or lung biopsy. A simple score based on clinical findings and pulse-oximetry might predict those children with poor short-term outcome.

Diagnosis and management of diffuse lung disease in children

Diffuse lung disease [DLD] in children comprises a group of heterogeneous, rare disorders. Despite the rarity of these diseases there has been a considerable increase in our knowledge of DLD in children including their diagnosis and management. Diagnosis of these diseases requires a detailed history and physical examination, diagnostic imaging, pulmonary function testing, selected and directed laboratory testing, bronchoalveolar lavage and in most cases an open lung biopsy. Once a diagnosis is made, treatment is centred on supportive care including nutritional and supplemental oxygen therapy when needed. Medications including corticosteroids and other immunomodulatory medications are often used. Lung transplantation has been used for final treatment in some cases of DLD. Formation of research collaborations will continue to further our understanding of these diseases.

Interstitial Lung Disease in Infants and Children: New Classification System with Emphasis on Clinical, Imaging, and Pathological Correlation

Interstitial lung diseases in infants and children comprise a rare heterogeneous group of parenchymal lung disorders, with clinical syndromes characterized by dyspnea, tachypnea, crackles, and hypoxemia. They arise from a wide spectrum of developmental, genetic, inflammatory, infectious, and reactive disorders. In the past, there has been a paucity of information and limited understanding regarding their pathogenesis, natural history, imaging findings, and histopathologic features, which often resulted in enormous diagnostic challenges and confusion. In recent years, there has been a substantial improvement in the understanding of interstitial lung disease in the pediatric patient, due to the development of a structured classification system based on etiology of the lung disease, established pathologic criteria for consistent diagnosis, and improvement of thoracoscopic techniques for lung biopsy. Imaging plays an important role in evaluating interstitial lung diseases in infants and children by confirming and characterizing the disorder, generating differential diagnoses, and providing localization for lung biopsy for pathological diagnosis. In this chapter, the authors present epidemiology, challenges and uncertainties of diagnosis, and amplify a recently developed classification system for interstitial lung disease in infants and children with clinical, imaging, and pathological correlation.

Infants and Young Children with Children's Interstitial Lung Disease

Though interstitial lung disease (ILD) can occur at any age in children, disorders more common in infancy and young children have received increased attention as an important group that is disproportionally affected, linked to lung development and lung injury, and represents disorders not seen in adult ILD. Identifying those children with potential children's ILD (chILD) and establishing a specific chILD diagnosis has evolved and is critical for pediatric pulmonologists, neonatologists, radiologists, and pathologists to recognize. Specific disorders more common in infancy include diffuse developmental disorders, growth abnormalities, pulmonary interstitial glycogenosis, neuroendocrine cell hyperplasia of infancy, and surfactant mutation dysfunction mutations. The presentation, evaluation, treatment, and clinical course are discussed for each of these specific disorders and other categories less common in infants and young children are briefly mentioned. Resources for physicians and families are also reviewed.

Diagnostic Pathology of Diffuse Lung Disease in Children

The pathologic classification of diffuse lung disease in children and adolescents has undergone revision in recent years in response to rapid developments and new discoveries in the field. A number of important advancements have been made in the last 10 years including the description of new genetic mutations causing severe lung disease in infants and children, as well as the description of new pathologic entities in infants. These recently described entities, including ABCA3 surfactant disorders, pulmonary interstitial glycogenosis, and neuroendocrine cell hyperplasia of infancy, are being recognized with increasing frequency. This review will include brief discussion of the etiology and pathogenesis of the major groups of diffuse lung disease in children. Histopathologic features are discussed for each of the major categories of diffuse lung disease in children, beginning with the genetic, developmental, and alveolar growth disorders common in infancy, followed by brief discussion of airway diseases, immunologic diseases, and pulmonary vascular diseases seen more commonly in older children. A protocol for handling pediatric wedge lung biopsies is also discussed, which optimizes the diagnostic yield of lung biopsies in this population.

Use and yield of chest computed tomography in the diagnostic evaluation of pediatric lung disease

OBJECTIVE

Computed tomography is commonly used in the diagnosis of pediatric lung disease. Although the radiation is not negligible, the yield has never been studied.

METHODS

Clinical and imaging data were collected for all children who underwent chest computed tomography, as part of the diagnostic process. Cases were grouped according to type of lung disease, based on clinical data and the question addressed to the radiologist. A positive yield was defined as computed tomography providing >or=1 of the following: (1) a diagnosis, (2) a clinically important new finding that had not been recognized previously, (3) alteration of the plan for further evaluation or treatment, or (4) exclusion of lung disease. No yield was defined when computed tomography did not add new information and did not affect evaluation or treatment.

RESULTS

Ages ranged from 2 weeks to 16 years, and 59% were male. The overall positive yield was 61% (64 of 105 cases). Yields were relatively low, that is, 23% (8 of 35 cases) for the evaluation of diffuse lung disease, 46% (6 of 13 cases) for localized disease, 50% (6 of 12 cases) for pleural disease, and 98% (41 of 42 cases) for congenital malformations.

CONCLUSIONS

The yield of chest computed tomography depends on the type of disease. Computed tomography has a significant yield for congenital anomalies. The yield is particularly low in the evaluation of acquired diffuse pulmonary disease and is relatively low in acquired focal lung disease. We suggest that chest computed tomography be used more judiciously.

Diffuse lung disease in young children: application of a novel classification scheme

RATIONALE

Considerable confusion exists regarding nomenclature, classification, and management of pediatric diffuse lung diseases due to the relative rarity and differences in the spectrum of disease between adults and young children.

OBJECTIVES

A multidisciplinary working group was formed to: (1) apply consensus terminology and diagnostic criteria for disorders presenting with diffuse lung disease in infancy; and (2) describe the distribution of disease entities, clinical features, and outcome in young children who currently undergo lung biopsy in North America.

METHODS

Eleven centers provided pathologic material, clinical data, and imaging from all children less than 2 years of age who underwent lung biopsy for diffuse lung disease from 1999 to 2004.

MEASUREMENTS AND MAIN RESULTS

Multidisciplinary review categorized 88% of 187 cases. Disorders more prevalent in infancy, including primary developmental and lung growth abnormalities, neuroendocrine cell hyperplasia of infancy, and surfactant-dysfunction disorders, constituted the majority of cases (60%). Lung growth disorders were often unsuspected clinically and under-recognized histologically. Cases with known surfactant mutations had characteristic pathologic features. Age at biopsy and clinical presentation varied among categories. Pulmonary hypertension, presence of a primary developmental abnormality, or ABCA3 mutation was associated with high mortality, while no deaths occurred in cases of pulmonary interstitial glycogenosis, or neuroendocrine cell hyperplasia of infancy.

CONCLUSIONS

This retrospective cohort study identifies a diverse spectrum of lung disorders, largely unique to young children. Application of a classification scheme grouped clinically distinct patients with variable age of biopsy and mortality. Standardized terminology and classification will enhance accurate description and diagnosis of these disorders.

Interstitial lung disease in infancy

OBJECTIVE

To describe the clinical profile of interstitial lung disease in infancy.

METHODS

A retrospective analysis of cases diagnosed to have ILD was carried out in Kanchi Kamakoti CHILDS Trust hospital over a period of 2 yr. Infants aged 1 month to 1 yr of age were included if they had (1) respiratory symptoms (Cough, tachypnea or crepitations) for at least 1 month (2) diffuse infiltrates on chest radiography (3) Hypoxemia as defined by oxygen saturation less than 90% by pulse oximetry and (4) High Resolution Computed Tomography (HRCT) of the chest revealing findings of interstitial infiltrates or ground glass pattern. Their case records were analyzed for clinical data, treatment and follow up details.

RESULTS

Of the 9 children, who were diagnosed to have ILD, 5 were boys and 4 were girls. The male: female ratio was 1.25: 1. The median age of onset of symptoms was 5 month. The common clinical features observed were tachypnea associated with chest indrawing (100%), cough (100%), hypoxia (100%), failure to thrive and fever (55%) each. The following radiographic patterns were observed in the chest skiagrams: reticulo-nodular pattern in 6(67%) and ground glass pattern in 3(33%). HRCT showed interstitial infiltrates in 6 (67%) and ground glass pattern in 3(33%). Evidence for cyto megalo virus (CMV) infection was detected in 5(56%), Adenovirus in 1 (11%) and Pneumocystis carinii (PCP) in 1(11%) infant. Open lung biopsy was performed in 2 infants, which detected CMV in 1 and PCP in the other. All children received oxygen therapy and systemic corticosteroids (oral/IV) in addition to specific therapy for infection and 3 of these infants succumbed to respiratory failure.

CONCLUSION

CMV Infection was the commonest cause of ILD in infancy in our study. However, the consequences on long term follow up in these infants need to be ascertained.

Congenital pulmonary lymphangiectasia

Congenital pulmonary lymphangiectasia (PL) is a rare developmental disorder involving the lung, and characterized by pulmonary subpleural, interlobar, perivascular and peribronchial lymphatic dilatation. The prevalence is unknown. PL presents at birth with severe respiratory distress, tachypnea and cyanosis, with a very high mortality rate at or within a few hours of birth. Most reported cases are sporadic and the etiology is not completely understood. It has been suggested that PL lymphatic channels of the fetal lung do not undergo the normal regression process at 20 weeks of gestation. Secondary PL may be caused by a cardiac lesion. The diagnostic approach includes complete family and obstetric history, conventional radiologic studies, ultrasound and magnetic resonance studies, lymphoscintigraphy, lung functionality tests, lung biopsy, bronchoscopy, and pleural effusion examination. During the prenatal period, all causes leading to hydrops fetalis should be considered in the diagnosis of PL. Fetal ultrasound evaluation plays a key role in the antenatal diagnosis of PL. At birth, mechanical ventilation and pleural drainage are nearly always necessary to obtain a favorable outcome of respiratory distress. Home supplemental oxygen therapy and symptomatic treatment of recurrent cough and wheeze are often necessary during childhood, sometimes associated with prolonged pleural drainage. Recent advances in intensive neonatal care have changed the previously nearly fatal outcome of PL at birth. Patients affected by PL who survive infancy, present medical problems which are characteristic of chronic lung disease.

A protocol for the handling of tissue obtained by operative lung biopsy: recommendations of the chILD pathology co-operative group

This is the first of a series on pediatric pulmonary disease that will appear as Perspectives in Pediatric Pathology over the coming months. The series will include practical issues, such as this protocol for handling lung biopsies and another on bronchoalveolar lavage in childhood, as well as reviews of advances in various areas in pediatric pulmonary pathology. It has been 11 years since the last Perspectives on pulmonary disease. Much has happened since then in this area, and this collection will highlight some emerging and rapidly advancing areas in pediatric lung disease. These will include a review of molecular mechanisms of lung development, and another of mechanisms of pulmonary vascular development. The surfactant system and its disorders, as well as recent advances in the biology of the pulmonary neuroendocrine system and mechanisms of respiratory viral disease, will be addressed. Articles on pulmonary hypertension, pulmonary neoplasia, and pediatric lung transplantation, with their implications for the pediatric pathologist, are also planned. The contributors to this series are a diverse group with special interests and expertise in these areas. As Dr. William Thurlbeck noted in his foreword to the previous volume, Pulmonary Disease, volume 18 of Perspectives in Pediatric Pathology, pediatric pathology had been largely concerned with phenomenology, rather than with mechanisms, model systems, and experimental investigation. I think he would have been pleased to see the changes that have occurred over the past 10 years in pediatric lung biology and pathology in particular, because these were particularly favored interests of his later years.

A role for MCP-1/CCR2 in interstitial lung disease in children

BACKGROUND

Interstitial lung diseases (ILD) are chronic inflammatory disorders leading to pulmonary fibrosis. Monocyte chemotactic protein 1 (MCP-1) promotes collagen synthesis and deletion of the MCP-1 receptor CCR2 protects from pulmonary fibrosis in ILD mouse models. We hypothesized that pulmonary MCP-1 and CCR2+ T cells accumulate in pediatric ILD and are related to disease severity.

METHODS

Bronchoalveolar lavage fluid was obtained from 25 children with ILD and 10 healthy children. Levels of pulmonary MCP-1 and Th1/Th2-associated cytokines were quantified at the protein and the mRNA levels. Pulmonary CCR2+, CCR4+, CCR3+, CCR5+ and CXCR3+ T cells were quantified by flow-cytometry.

RESULTS

CCR2+ T cells and MCP-1 levels were significantly elevated in children with ILD and correlated with forced vital capacity, total lung capacity and ILD disease severity scores. Children with lung fibrosis had significantly higher MCP-1 levels and CCR2+ T cells in bronchoalveolar lavage fluid compared to non-fibrotic children.

CONCLUSION

The results indicate that pulmonary CCR2+ T cells and MCP-1 contribute to the pathogenesis of pediatric ILD and might provide a novel target for therapeutic strategies.

Pediatric interstitial lung disease revisited

The spectrum of pediatric interstitial lung disease (PILD) includes a diverse group of rare disorders characterized by diffuse infiltrates and disordered gas exchange. Children with these conditions typically present with tachypnea, crackles, and hypoxemia. Recent advances have been made in the identification of different types of PILD that are unique to infancy. More exciting has been the discovery of genetic abnormalities of surfactant function, now described in both children and adults. A systematic evaluation of the child presenting with diffuse infiltrates of unknown etiology is essential to the diagnosis. Most often, lung biopsy is required. Current treatment options remain less than satisfactory, and morbidity and mortality remain considerable.

Diagnosis of interstitial lung disease in children

Chronic interstitial lung disease (ILD) in infants and children is a challenging diagnostic clinical problem. There are many unresolved and controversial issues in the diagnosis of this heterogeneous group of uncommon disorders in children. Diagnosis requires a high index of suspicion as the initial clinical manifestations are subtle, highly variable and non-specific. There is no consensus for the clinical diagnostic criteria of paediatric ILD. The spectrum of clinical findings is highly variable. The diagnostic evaluation of a child with suspected ILD includes a comprehensive history, physical examination, oxygen saturation (at rest, during exercise or during feeding), a plain chest x ray and a high-resolution thin-cut tomography scan of the chest. Pulmonary function studies can be useful in older children; these typically show a restrictive pattern with a decreased forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC) and total lung capacity, but normal FEV(1)/FVC. A systematic approach to diagnosis is useful in the evaluation of an infant or child with suspected chronic ILD. Due to the rarity of most of these disorders, multi-centre collaboration is needed to improve our understanding of this orphan lung disease.

Pneumonite intersticial crónica

Interstitial lung disease includes a group of chronic diseases characterized by alterations in alveolar walls and loss of functional alveolar-capillary units. These are rare diseases in children, mostly with an unknown cause and associated with a high morbidity and mortality due to insufficient therapeutic effectiveness. The authors report a case of a previously healthy 3 years old child who presented with wheezing and severe respiratory insufficiency following a respiratory infection. The investigation performed led to the diagnosis of chronic interstitial pneumonitis. Several treatments have been tried (corticosteroids, hydroxychloroquine, N-acetylcysteine) without any obvious improvement.

Computed tomography of diffuse interstitial lung disease in children

Unlike diseases of the airways, interstitial lung diseases in childhood are exceedingly rare and are usually associated with significant morbidity and mortality. Interstitial lung disease in the paediatric age group is a particular diagnostic challenge because the clinical presentation and radiographic features are so non-specific. High resolution computed tomography (HRCT) has proved its worth in adults with interstitial lung disease and has a role, albeit more limited, in the non-invasive evaluation of paediatric interstitial lung disease.

A family with extrinsic allergic alveolitis caused by wild city pigeons: A case report

We describe a family in which the mother died of unresolved lung disease and whose 5 children, some of whom had previous signs of asthma, were subsequently affected by extrinsic allergic alveolitis caused by contact with wild city pigeon antigens. The children received systemic corticosteroids for 1 month and inhaled steroids for 24 months, while antigen exposure was reduced as much as feasible. This was followed by a quick clinical recovery and a slow normalization of chest radiographs and pulmonary function indices, especially of diffusion capacity, during a follow-up of 24 months. Because pigeon-breeder's lung caused by free-roaming city pigeons has not been previously described, it remains unclear whether this family developed the disease because of high antigen exposure or because of increased susceptibility. None of the supposedly high-risk human leukocyte antigen types were found in the children. Whether human leukocyte antigen B7 in 1 child played a role in the course of the illness remains speculative. It is unknown to what extent pigeon-breeder's lung caused by nondomestic birds remains undetected and misdiagnosed as difficult or steroid-resistant asthma. The question remains whether free-roaming city pigeons are indeed a public health risk. We suggest that atypical outdoor antigens be considered in all patients with nonresolving chest disease or therapy-resistant asthma.

Investigation of the child with interstitial lung disease

Many disorders can affect the pulmonary interstitium in children. Although individual interstitial lung diseases are rare, the range of conditions encountered is wide. Interstitial disease is also seen increasingly as a consequence of the treatment of children having other primary problems including cancer, immunodeficiency and haemotological diseases, as well as in recipients of solid organ and bone marrow transplants. The management and prognosis of individual conditions is highly variable, thus it is essential to search for a precise diagnosis in every patient. High resolution computerised tomography (HRCT) and other less invasive investigations may be helpful in the management of patients. However, it is unusual to be able to make a firm diagnosis without a lung biopsy.

Steroid-refractory neonatal eosinophilic pneumonia responsive to cyclosporin A

Idiopathic neonatal eosinophilic pneumonia is extremely rare. We report an infant who presented with tachypnea and interstitial infiltrates on chest radiograph at age 2 wk. Lung biopsy revealed perivascular and interstitial eosinophils. Despite initial improvement, the patient's condition became resistant to corticosteroids, cromolyn, and intravenous gamma globulin. After treatment with cyclosporin A his symptoms resolved.

Current concepts on interstitial lung disease in children

Pediatric interstitial lung disease comprises a diverse group of rare conditions characterized by an infiltrative process, abnormal gas exchange, and restrictive lung disease. Although the disorder is similar to its adult counterpart, its course is complicated by the continued need for lung growth and differentiation in infants and children. Knowledge about the pathogenesis, prognosis, and treatment of pediatric interstitial lung disease is limited. Investigators are focusing on defining the cellular mediators of the interstitial damage and describing the role of viral infections in and possible genetic predisposition to interstitial lung disease. Clinicians continue to define the various types of interstitial lung disease and to evaluate the roles of bronchoalveolar lavage, radiography, and biopsy in diagnosis. Together, investigators are working toward the development of specific, targeted therapy that will reduce the significant morbidity and mortality seen in pediatric interstitial lung disease.