Interstitial lung diseases (ILDs) in children constitute a heterogeneous group of rare diseases that have been described and classified according to experiences and research in adults. However, pediatric pulmonologists have observed that the clinical spectrum is broader in children than in adults, and that many of these disorders have different courses and treatment responses. In addition, probably due to the various stages of lung development and maturation, new clinical forms have been described, particularly in infants. This has broadened the classification of ILDs in this age bracket. The understanding that neither the usual definition nor the standard classification of these disorders entirely apply to children has prompted multicenter studies designed to increase knowledge of these disorders, as well as to standardize diagnostic and therapeutic strategies. We have reviewed the conceptualization of ILDs in children, taking into consideration the particularities of this group of patients when using the criteria for the classification of these diseases in adults. We have also made a historical review of several multicenter studies in order to further understanding of the problem. We have emphasized the differences in the clinical presentation, in an attempt to highlight knowledge of newly described entities in young children. We underscore the need to standardize management of laboratory and radiological routines, as well as of lung biopsy processing, taking such knowledge into account. It is important to bear in mind that, among the recently described disorders, genetic surfactant dysfunction, which is often classified as an idiopathic disease in adults, should be included in the differential diagnosis of ILDs.

Keywords: Lung diseases, interstitial; Lung diseases, interstitial/diagnosis; Lung diseases, interstitial/therapy; Child.

Objective: To assess the relative frequency of incident cases of interstitial lung diseases (ILDs) in Brazil. Methods: This was a retrospective survey of new cases of ILD in six referral centers between January of 2013 and January of 2020. The diagnosis of ILD followed the criteria suggested by international bodies or was made through multidisciplinary discussion (MDD). The condition was characterized as unclassifiable ILD when there was no specific final diagnosis following MDD or when there was disagreement between clinical, radiological, or histological data. Results: The sample comprised 1,406 patients (mean age = 61 ± 14 years), and 764 (54%) were female. Of the 747 cases exposed to hypersensitivity pneumonitis (HP)-related antigens, 327 (44%) had a final diagnosis of HP. A family history of ILD was reported in 8% of cases. HRCT findings were indicative of fibrosis in 74% of cases, including honeycombing, in 21%. Relevant autoantibodies were detected in 33% of cases. Transbronchial biopsy was performed in 23% of patients, and surgical lung biopsy, in 17%. The final diagnoses were: connective tissue disease-associated ILD (in 27%), HP (in 23%), idiopathic pulmonary fibrosis (in 14%), unclassifiable ILD (in 10%), and sarcoidosis (in 6%). Diagnoses varied significantly among centers (?2 = 312.4; p < 0.001). Conclusions: Our findings show that connective tissue disease-associated ILD is the most common ILD in Brazil, followed by HP. These results highlight the need for close collaboration between pulmonologists and rheumatologists, the importance of detailed questioning of patients in regard with potential exposure to antigens, and the need for public health campaigns to stress the importance of avoiding such exposure.

Keywords: Lung diseases, interstitial/epidemiology; Alveolitis, extrinsic allergic/epidemiology; Connective tissue diseases/epidemiology, Sarcoidosis/epidemiology; Idiopathic pulmonary fibrosis/epidemiology

Objective: To determine the interobserver and intraobserver agreement in the diagnosis of interstitial lung diseases (ILDs) based on HRCT scans and the impact of observer expertise, clinical data and confidence level on such agreement. Methods: Two thoracic radiologists and two general radiologists independently reviewed the HRCT images of 58 patients with ILDs on two distinct occasions: prior to and after the clinical anamnesis. The radiologists selected up to three diagnostic hypotheses for each patient and defined the confidence level for these hypotheses. One of the thoracic and one of the general radiologists re-evaluated the same images up to three months after the first readings. In the coefficient analyses, the kappa statistic was used. Results: The thoracic and general radiologists, respectively, agreed on at least one diagnosis for each patient in 91.4% and 82.8% of the patients. The thoracic radiologists agreed on the most likely diagnosis in 48.3% (κ = 0.42) and 62.1% (κ = 0.58) of the cases, respectively, prior to and after the clinical anamnesis; likewise, the general radiologists agreed on the most likely diagnosis in 37.9% (κ = 0.32) and 36.2% (κ = 0.30) of the cases. For the thoracic radiologist, the intraobserver agreement on the most likely diagnosis was 0.73 and 0.63 prior to and after the clinical anamnesis, respectively. That for the general radiologist was 0.38 and 0.42.The thoracic radiologists presented almost perfect agreement for the diagnostic hypotheses defined with the high confidence level. Conclusions: Interobserver and intraobserver agreement in the diagnosis of ILDs based on HRCT scans ranged from fair to almost perfect and was influenced by radiologist expertise, clinical history and confidence level.

Keywords: Lung diseases, interstitial; Tomography, X-ray computed; Observer variation.

Many conditions result in chronic interstitial lung disease (ILD), being classified as fibrosing ILDs, including idiopathic pulmonary fibrosis, connective tissue diseases, sarcoidosis, and fibrotic hypersensitivity pneumonitis. HRCT plays an important role in the clinical evaluation of fibrosing ILDs. Current treatment perspectives are encouraging and reinforce the need for HRCT scans of adequate technical quality for early detection of fibrosing ILD. Despite efforts in this regard, the significance and management of imaging findings of early interstitial lung abnormalities have yet to be clarified. After identification of CT findings consistent with fibrosing ILD, radiologists must be able to identify characteristic morphological patterns and, in some cases, features of specific clinical entities. In cases in which HRCT features are not sufficiently specific for a definitive diagnosis, HRCT can aid in selecting the best site for surgical lung biopsy. CT follow-up is useful for identifying progressive fibrosing ILDs and detecting complications unrelated to the underlying disease, including infections, acute exacerbations, and neoplasms. Automated quantification tools have clinical applicability and are likely to be available for use in imaging analysis in the near future. In addition, incorporation of CT evaluation into scoring systems based on clinical and functional parameters for staging fibrosing disease is likely to become valuable in determining prognosis. Knowledge of the clinical applications of CT evaluation is essential for specialists managing patients with fibrosing ILD and can have a positive impact on the clinical course of the disease.

Keywords: Tomography, X-ray computed; Diagnostic imaging; Pulmonary fibrosis.

Objective: Mobile health (mHealth) applications are scarce for children and adolescents with chronic pulmonary diseases (CPDs). This study aimed to map and describe the contents of the mHealth apps available for use in children and adolescents with CPDs. Methods: We performed a systematic mapping review of published scientific literature in PubMed, Scopus, and Cochrane Library by February of 2023, using relevant keywords. Inclusion criteria were as follows: children aged < 18 years with CPDs; and studies published in English on mHealth apps. Results: A total number of 353 studies were found, 9 of which met the inclusion criteria. These studies described seven mHealth apps for Android and iOS, designed either for asthma (n = 5) or for cystic fibrosis (n = 2). Five content areas were identified: education/information; pharmacological treatment; emergency; support; and non-pharmacological treatment. The studies (4, 2, and 3, respectively) showed consistent findings using qualitative, quantitative, and mixed methodologies. Conclusions: This mapping review provided a guided selection of the most appropriate mHealth apps for use in children and adolescents with CPDs based on the needs of each target population. However, these mHealth apps have limited capabilities to reinforce disease self-management and provide information related to treatment compliance.

Keywords: Lung diseases; Child, Adolescent; Treatment adherence and compliance; Telemedicine; Self-management.

Objective: Respiratory muscle weakness is a functional repercussion of chronic lung disease (CLD). The objective of this study was to assess the effects of home-based respiratory muscle training (RMT) in children and adolescents with CLD or neuromuscular disease (NMD). Methods: This was a quasi-experimental study involving children and adolescents with CLD or NMD. Before and after 6 months of home-based RMT, we measured respiratory muscle strength (MIP and MEP), PEF, and peak cough flow (PCF). We made statistical comparisons between the pre-RMT and post-RMT values, as well as evaluating the correlation between the duration and effect of RMT. Results: The study included 29 patients, with a mean age of 12 years (range, 5-17 years), of whom 18 (62.1%) were male. The CLD group comprised 11 patients (37.9%), and the NMD group comprised 18 (62.1%). The mean duration of the RMT was 60 weeks (range, 46-90 weeks) in the CLD group and 39 weeks (range, 24-89 weeks) in the NMD group. In comparison with the pre-RMT values, the post-RMT values for MIP and MEP were significantly higher in both groups, whereas those for PEF and PCF were significantly higher only in the NMD group. We found no correlation between the duration and the effect of RMT. Conclusions: Home-based RMT appears to be an effective strategy for increasing respiratory muscle strength in children and adolescents with CLD or NMD, although it increased the ability to cough effectively only in those with NMD.

Keywords: Breathing exercises; Cystic fibrosis; Bronchiolitis obliterans; Neuromuscular diseases; Cough.

Interstitial lung diseases (ILDs) are heterogeneous disorders, involving a large number of conditions, the approach to which continues to pose an enormous challenge for pulmonologists. The 2012 Brazilian Thoracic Association ILD Guidelines were established in order to provide Brazilian pulmonologists with an instrument that can facilitate the management of patients with ILDs, standardizing the criteria used for the diagnosis of different conditions and offering guidance on the best treatment in various situations. The objective of this article was to briefly describe the highlights of those guidelines.

Keywords: Lung diseases, interstitial; Guidelines as topic; Brazil.

Introduction: The diagnosis of diffuse lung disease is still a challenge for the pediatric intensive care physician. Routine clinical examinations and laboratory tests are frequently negative. The objective of this study was to evaluate the diagnostic potential, the impact on therapy and the rate of complications of open lung biopsy in children with undiagnosed diffuse lung disease, respiratory failure and inappropriate response to initial therapy. Methods: From January 1987 to January 1997, 29 children with diffuse pulmonary disease of unknown etiology, respiratory failure (PaO2 /FiO2 < 300) and no response to previous treatments were considered for open lung biopsy. Newborns, children with known chronic pulmonary disease and children with untreatable shock or coagulopathy were excluded. All biopsies were performed by a thoracic surgeon by a microthoracotomy in the lung shown to be the most affected by X-ray examination. Tissue samples were analyzed in terms of cultures, light microscopy, electron microscopy and immunofluorescence microscopy, according to the pathologist's decision. Results: All biopsies (100%) resulted in at least one histological diagnosis and in 20 patients (68.9%) it was obtained a specific diagnosis. The most frequent histological patterns found were: non-specific interstitial pneumonitis with variable degrees of fibrosis in 18 cases; bronchiolitis in eight cases and pulmonary hypertension in three cases. Regarding the most frequent specific diagnosis, six children were found with cytomegalovirus infection, three with Pneumocystis carinii, three with adenovirus and three with respiratory syncytial virus infection. These data induced a change in therapy in 20 children (68.9%). The most frequent changes in therapy were the use of corticosteroids in 14 children and a review of the antibiotic regimen in six patients. Seven patients (24.1%) presented with complications that were easily resolved. There were 13 deaths, probably due to the critical conditions of these patients, all unrelated to the procedure. Conclusions: Open lung biopsy, though an invasive procedure, should be considered in the evaluation of selected children with undiagnosed diffuse lung disease, respiratory failure and with no satisfactory response to previous therapies.

On HRCT scans, lung cysts are characterized by rounded areas of low attenuation in the lung parenchyma and a well-defined interface with the normal adjacent lung. The most common cystic lung diseases are lymphangioleiomyomatosis, Langerhans cell histiocytosis, and lymphocytic interstitial pneumonia. In a retrospective analysis of the HRCT findings in 50 patients diagnosed with chronic paracoccidioidomycosis, we found lung cysts in 5 cases (10%), indicating that patients with paracoccidioidomycosis can present with lung cysts on HRCT scans. Therefore, paracoccidioidomycosis should be included in the differential diagnosis of cystic lung diseases.

Keywords: Paracoccidioidomycosis; Cysts; Multidetector computed tomography.

The approach described below is an attempt to make order out of chaos for the pathologists dealing with diffuse lung disease and to provide radiologists some information about the histology of interstitial lung disease as it applies to HRCT. Obviously, the approach outlined is not applicable to all situations and many cases remain insoluble. Nevertheless, it does give the pathologist a framework within which interstitial lung disease can be assessed, and helps to develop a differential diagnosis histologically. The author thinks this approach also shows good correlation with many of the changes observed by the chest radiologist with HRCT of the lung. Recognizing an anatomic distribution may not necessarily be correlated with how a lesion is clinically viewed. For example, bronchiolocentricity is an important and prominent feature in hypersensitivity pneumonitis and respiratory bronchiolitis associated with interstitial lung disease, but neither is clinically considered an airway disease. The authors also make comments about transbronchial biopsy in opposition to open-lung biopsy in the pathologic assessment of difuse lung disease, although HRCT does provide information to the clinician to help select the most appropriate biopsy modality. Obviously, open-lung biopsy (and those retrieved by thoracoscopic techniques) offer more tissue and make it easier to observe anatomic distribution and reaction patterns. Nevertheless, transbronchial biopsies often include sufficient tissue (although fragmented) and the pathologist is able to mentally reconstruct the distribution and reaction pattern. Obviously, the changes assessed in transbronchial biopsy have to be individualized on a case-by-case basis, but it is surprising how often they are useful when carefully correlated with the clinical and radiological features in a given case.

Keywords: Pulmonary interstitial disorders. Pathology. Pulmonary fibrosis. Pulmonary biopsy.

Macrolides are drugs that have antimicrobial effects, especially against intracellular pathogens. Various studies have shown that macrolides might also have anti-inflammatory effects. Macrolides inhibit the production of interleukins and can reduce pulmonary neutrophilic inflammation. Clinical trials have demonstrated beneficial effects of macrolides in various chronic lung diseases. The objective of this study was to review recent data in the medical literature on the anti-inflammatory effects of macrolides in childhood lung diseases by searching the Medline (PubMed) database. We used the following search terms: "macrolide and cystic fibrosis"; "macrolide and asthma"; "macrolide and bronchiolitis obliterans"; and "macrolide and acute bronchiolitis". We selected articles published in international scientific journals between 2001 and 2012. Clinical studies and in vitro evidence have confirmed the anti-inflammatory effect of macrolides in respiratory diseases. Some clinical trials have shown the benefits of the administration of macrolides in patients with cystic fibrosis, although the risk of bacterial resistance should be considered in the analysis of those benefits. Such benefits are controversial in other respiratory diseases, and the routine use of macrolides is not recommended. Further controlled clinical trials are required in order to assess the efficacy of macrolides as anti-inflammatory drugs, so that the benefits in the treatment of each specific clinical condition can be better established.

Keywords: Macrolides; Asthma; Cystic Fibrosis; Bronchiolitis.

The present article purports to analyze aspects related to the concept of quality of life, taking into account the relevance of setting down parameters that allow for the evaluation of those aspects, especially in patients with chronic diseases. The analysis considered quality of life as one of the essential components of medical care, and pointed out the precautions that should be taken to choose instruments of evaluation, that should be sensitive and reliable to the dimensions they intend to evaluate.

Keywords: quality of life, chronic diseases, asthma, chronic obstructive pulmonary disease

Neuromuscular diseases affect alveolar air exchange and therefore cause chronic respiratory failure. The onset of respiratory failure can be acute, as in traumas, or progressive (slow or rapid), as in amyotrophic lateral sclerosis, muscular dystrophies, diseases of the myoneural junction, etc. Respiratory muscle impairment also affects cough efficiency and, according to the current knowledge regarding the type of treatment available in Brazil to these patients, it can be said that the high rates of morbidity and mortality in these individuals are more often related to the fact that they cough inefficiently rather than to the fact that they ventilate poorly. In this review, with the objective of presenting the options of devices available to support and substitute for natural ventilation in patients with neuromuscular diseases, we have compiled a brief history of the evolution of orthopedic braces and prostheses used to aid respiration since the end of the 19th century. In addition, we highlight the elements that are fundamental to the diagnosis of alveolar hypoventilation and of failure of the protective cough mechanism: taking of a clinical history; determination of peak cough flow; measurement of maximal inspiratory and expiratory pressures; spirometry in two positions (sitting and supine); pulse oximetry; capnography; and polysomnography. Furthermore, the threshold values available in the literature for the use of nocturnal ventilatory support and for the extension of this support through the daytime period are presented. Moreover, the maneuvers used to increase cough efficiency, as well as the proper timing of their introduction, are discussed.

Keywords: Respiratory insufficiency/diagnosis; Chronic disease; Respiratory insufficiency/therapy;