A 35 year-old black woman, previously healthy, who complained about chronic cough and shortness of breath was investigated after non-response of symptoms. Her chest X-ray and high resolution chest CT-scan were normal. She presented with abnormal spirometry, a mild restrictive disturbance. After a negative initial clinical investigation, an open lung biopsy was indicated. Multiple microscopic peribronchiolar tumorlets carcinoids - neuroendocrine cell hyperplasia was revealed. The authors emphasize the importance of an early diagnosis of this unusual entity and discuss its possible pathophysiological mechanisms.

Keywords: Lung diseases. Neuroendocrine cell. Bronchiolitis. Carcinoid. Tumorlets.

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia with airflow obstruction is a rare form of lung injury. All of the reported cases have been diagnosed by surgical lung biopsy. Only three of the reported cases presented with diffuse interstitial lung opacities on HRCT scans. We report three additional cases of this entity. All of the patients were female and presented with mild-to-moderate airflow obstruction. In the first case, transbronchial biopsy and imaging data were sufficient to make the diagnosis. Although the HRCT scans of all three cases revealed a mosaic pattern, that of the third patient also revealed diffuse interstitial infiltrate. In extremely rare cases, HRCT findings can simulate those seen in other interstitial lung diseases.

Keywords: Neuroendocrine cells; Carcinoid tumor; Bronchiolitis obliterans.

High-resolution computed tomography (HRCT) is the radiological imaging technique best suited to revealing changes in lung structure. Various HRCT findings, taken together, can represent typical patterns. These patterns, in conjunction with the anatomical distribution of findings and with clinical data, can narrow the differential diagnosis of diffuse interstitial lung disease and, in many cases, indicate the correct diagnosis with a high degree of accuracy. The most common HRCT patterns seen in cases of diffuse interstitial lung diseases are the nodular pattern, linear/reticular opacities, cystic lesions, ground-glass opacities and consolidations. This article reviews the correlations between HRCT patterns and pathologic findings, summarizing the most common causes, as well as detailing the methods of investigation employed in order to diagnose the most common types of chronic diffuse lung disease.

Keywords: Lung diseases, interstitial/pathology; Tomography, X-Ray computed; Diagnostic techniques, respiratory system.

Objective: To evaluate clinical, functional, and CT characteristics, as well as disease progression, in patients with idiopathic inflammatory myopathy-associated interstitial lung disease (IIM-ILD) treated at a referral center in Brazil. Methods: This was a retrospective cohort study analyzing demographic characteristics, clinical variables, pulmonary function test results, HRCT findings, serological profiles, treatments, and outcomes. Results: Seventy-nine IIM-ILD patients were included in the present study. The mean follow-up period was 8.7 ± 4.7 years. The most common diagnosis was antisynthetase syndrome, observed in 51 (64.5%) of the 79 patients. The most common symptoms were dyspnea (in 94.9%), arthralgia (in 82.2%), and muscle weakness (in 75.9%). Mean baseline FVC was 2.19 ± 0.75 L, corresponding to 62.5% of the predicted value. During follow-up, FVC showed significant improvement. The most common CT patterns were indeterminate (in 44.4%) and nonspecific interstitial pneumonia (in 35.4%). Treatment most frequently included prednisone (in 98.7%), azathioprine (in 92.3%), or methotrexate (in 57.7%). Overall survival was 84.8%. Mortality was higher among patients who developed pulmonary hypertension and those who required intravenous methylprednisolone pulse therapy. Conclusions: Most patients with IIM-ILD progress well with immunosuppressive therapy. Pulmonary hypertension and the need for methylprednisolone pulse therapy appear to be associated with higher mortality.

Keywords: Lung diseases, interstitial; Myositis; Antisynthetase syndrome; Tomography; Spirometry.

Objective: To evaluate the role of video-assisted thoracoscopy in the diagnosis of diffuse parenchymal lung diseases. Methods: The medical charts of patients suspected of having diffuse parenchymal lung disease were retrospectively reviewed, as were the results of the anatomopathological examination of lung biopsy specimens collected through video-assisted thoracoscopy. Results: Of the 48 patients included in the study, 25 (52.08%) were female and 23 (47.92%) were male. The mean age was 58.77 years (range, 20-76 years). A total of 54 biopsy fragments were submitted to anatomopathological examination: 24 (44.44%) from the lingula; 10 (18.52%) from the left lower lobe; 7 (12.96%) from the right middle lobe; 6 (11.11%) from the right lower lobe; 5 (9.26%) from the left upper lobe; and 2 (3.71%) from the right upper lobe. The mean duration of thoracic drainage was 2.2 days. Adverse events included conversion to thoracotomy, in 2 patients (4.17%), and residual pneumothorax, in 1 (2.08%). The definitive diagnosis was made in 46 patients (95.83%), and idiopathic interstitial pneumonia was the predominant diagnosis (in 54.18%). The most common diagnoses were usual interstitial pneumonia (in 29.27%), nonspecific interstitial pneumonia (in 16.67%) and hypersensitivity pneumonia (in 12.50%). Conclusions: Lung biopsy through video-assisted thoracoscopy is a safe, effective and viable procedure for the diagnosis of diffuse parenchymal lung diseases.

Keywords: Lung diseases, interstitial; Thoracoscopy; Diagnosis.

Objective: The frequency of obstructive sleep apnea (OSA) in patients with idiopathic pulmonary fibrosis (IPF) is high. The clinical course of non-IPF interstitial lung disease (ILD) can be similar to that of IPF. We sought to assess the frequency and predictors of OSA in patients with non-IPF fibrotic ILD, as well as the impact of positive airway pressure (PAP) therapy on the quality of life of such patients. Methods: This was a prospective study in which non-IPF fibrotic ILD patients underwent a home sleep apnea test. The patients with and without OSA were compared, and a multivariate logistic regression model was used to identify independent predictors of OSA. At 3 months after initiation of PAP therapy, we evaluated the participating patients for respiratory events, nocturnal hypoxemia, and changes in quality of life. Results: Of a total of 50 patients, 50% were male, and 76% were diagnosed with OSA. The mean age was 67.8 ± 8.3 years. The patients with OSA had significantly lower TLC (p = 0.033) and awake SpO2 (p = 0.023) than did those without OSA. In the multivariate logistic regression model, SpO2 (OR = 0.46; p = 0.016) and TLC (OR = 0.95; p = 0.026) remained significantly associated with OSA risk. A total of 12 patients received PAP therapy. At 3 months after initiation of PAP therapy, 91.7% were well controlled, Epworth Sleepiness Scale scores decreased significantly (p = 0.006), and emotional well-being tended to improve (p = 0.068). PAP therapy corrected nocturnal hypoxemia in all patients. Conclusions: We found a high frequency of OSA in patients with non-IPF fibrotic ILD. A low TLC was an independent predictor of a higher risk of OSA. PAP therapy can correct nocturnal hypoxemia. There should be a low threshold for suspicion of OSA and initiation of PAP therapy in patients with non-IPF fibrotic ILD.

Keywords: Sleep apnea, obstructive; Fibrosis, pulmonary; Total lung capacity; Hypoxia; Quality of life.

Respiratory bronchiolitis-associated interstitial lung disease is one of many within the spectrum of smoking-related diffuse infiltrative lung diseases. The clinical and functional characteristics are typically subtle. Herein, we describe two cases of diagnosed through open-lung biopsy, and characterized by insidious evolution of dyspnea, digital clubbing, cystic lesions on computed tomography scans, and hipoxemia upon exertion. We emphasize that, when smokers are evaluated, it is imprtant to consider a diagnosis of respiratory bronchiolitis-associated interstitial lung disease in the context of interstitial cystitis, as well as in that of lymphangioleiomyomatosis, eosinophilic granuloma and idiophatic pulmonary fibrosis.

Keywords: Smoking. Interstitial lung diseases. Bronchiolitis.

Many interstitial lung diseases (ILDs) share mechanisms that result in a progressive fibrosing phenotype. In Brazil, the most common progressive fibrosing interstitial lung diseases (PF-ILDs) are chronic hypersensitivity pneumonitis, idiopathic pulmonary fibrosis, unclassified ILD, and connective tissue diseases. PF-ILD is seen in approximately 30% of patients with ILD. Because PF-ILD is characterized by disease progression after initiation of appropriate treatment, a diagnosis of the disease resulting in fibrosis is critical. Different criteria have been proposed to define progressive disease, including worsening respiratory symptoms, lung function decline, and radiological evidence of disease progression. Although the time elapsed between diagnosis and progression varies, progression can occur at any time after diagnosis. Several factors indicate an increased risk of progression and death. In the last few years, antifibrotic drugs used in patients with idiopathic pulmonary fibrosis have been tested in patients with PF-ILD. The effects of nintedanib and placebo have been compared in patients with PF-ILD, a mean difference of 107.0 mL/year being observed, favoring nintedanib. The U.S. Food and Drug Administration and the Brazilian Health Regulatory Agency have approved the use of nintedanib in such patients on the basis of this finding. Pirfenidone has been evaluated in patients with unclassified ILD and in patients with other ILDs, the results being similar to those for nintedanib. More studies are needed in order to identify markers of increased risk of progression in patients with ILD and determine the likelihood of response to treatment with standard or new drugs.

Keywords: Alveolitis, extrinsic allergic; Idiopathic pulmonary fibrosis; Lung diseases, interstitial; Connective tissue diseases.

Connective tissue disease-associated interstitial lung disease (CTD-ILD) represents a group of systemic autoimmune disorders characterized by immune-mediated organ dysfunction. Systemic sclerosis, rheumatoid arthritis, idiopathic inflammatory myositis, and Sjögren's syndrome are the most common CTDs that present with pulmonary involvement, as well as with interstitial pneumonia with autoimmune features. The frequency of CTD-ILD varies according to the type of CTD, but the overall incidence is 15%, causing an important impact on morbidity and mortality. The decision of which CTD patient should be investigated for ILD is unclear for many CTDs. Besides that, the clinical spectrum can range from asymptomatic findings on imaging to respiratory failure and death. A significant proportion of patients will present with a more severe and progressive disease, and, for those, immunosuppression with corticosteroids and cytotoxic medications are the mainstay of pharmacological treatment. In this review, we summarized the approach to diagnosis and treatment of CTD-ILD, highlighting recent advances in therapeutics for the various forms of CTD.

Keywords: Lung diseases, interstitial; Collagen diseases; Scleroderma, systemic; Arthritis, rheumatoid; Myositis; Therapeutics.

We report the case of a 56-year-old patient who underwent left single lung transplantation for idiopathic pulmonary fibrosis (IPF). Despite the high level of immunosuppression after the surgery, there was rapid progression to IPF in the native (right) lung as demonstrated by thoracoscopic lung biopsy. After 104 days on mechanical ventilation, the patient underwent right lung transplant and was discharged from the hospital on postoperative day 26.

Keywords: Idiopathic pulmonary fibrosis; Lung transplantation; Case reports [publication type].

The initial evaluation of patients with interstitial lung disease (ILD) primarily involves a comprehensive, active search for the cause. Autoantibody assays, which can suggest the presence of a rheumatic disease, are routinely performed at various referral centers. When interstitial lung involvement is the condition that allows the definitive diagnosis of connective tissue disease and the classical criteria are met, there is little debate. However, there is still debate regarding the significance, relevance, specificity, and pathophysiological role of autoimmunity in patients with predominant pulmonary involvement and only mild or benign symptoms of connective tissue disease. The purpose of this article was to review the current knowledge of autoantibody positivity and to discuss its possible interpretations in patients with ILD and without clear etiologic associations, as well as to enhance the understanding of the natural history of an allegedly new disease and to describe the possible prognostic implications. We also discuss the proposition of a new term to be used in the classification of ILDs: lung-dominant connective tissue disease.

Keywords: Idiopathic interstitial pneumonias; Autoantibodies; Connective tissue diseases; Autoimmune diseases; Diagnosis, differential.

Objective: To make a retrospective analysis of lung biopsy samples obtained from patients diagnosed with chronic idiopathic interstitial pneumonia, as defined in the American Thoracic Society/European Respiratory Society classification system made public in 2000. Methods: Samples from 252 open-lung biopsies of patients with interstitial lung disease, all performed between 1977 and 1999, were reviewed, and 39 cases of idiopathic interstitial lung disease were selected and re-evaluated by two pathologists in accordance with the American Thoracic Society/European Respiratory Society classification system. Results: Among those 39 cases, the diagnoses were maintained in 28 (71.8%). A new pathologic entity, nonspecific interstitial pneumonia, was included in the reclassification, and overlapping patterns were observed in 6 cases. Of the 28 cases in which the diagnosis of chronic idiopathic interstitial pneumonia remained unchanged, idiopathic pulmonary fibrosis was accompanied by cryptogenic organizing pneumonia in 4, cryptogenic organizing pneumonia was accompanied by nonspecific interstitial pneumonia in 1, and desquamative interstitial pneumonia was accompanied by nonspecific interstitial pneumonia in 1. All cases of idiopathic pulmonary fibrosis were confirmed, although 3 of those were found to be accompanied by cryptogenic organizing pneumonia. Virtually all prior diagnoses were maintained in the review of the biopsy samples (p > 0,05). Conclusion: The American Thoracic Society/European Respiratory Society system of classifying interstitial lung disease is a useful tool for pathologists who deal with lung biopsies.

Keywords: Pulmonary fibrosis; Lung diseases, interstitial

Objective: To study the clinical, radiological, and histopathological patterns of transbronchial biopsy (TBB) used in order to confirm the diagnosis in patients with clinical suspicion of interstitial lung disease (ILD) treated at a tertiary-care university hospital. Methods: We reviewed the medical records, radiology reports, and reports of transbronchial biopsies from all patients with suspected ILD who underwent TBB between January of 1999 and December of 2006 at the Hospital das Clínicas de Botucatu, located in the city of Botucatu, Brazil. Results: The study included 56 patients. Of those, 11 (19.6%) had a definitive diagnosis of idiopathic pulmonary fibrosis (IPF), the rate of which was significantly higher in the patients in which ILD was a possible diagnosis in comparison with those in which ILD was the prime suspect (p = 0.011), demonstrating the contribution of TBB to the diagnostic confirmation of these diseases. The histopathological examination of the biopsies revealed that 27.3% of the patients with IPF showed a pattern of organizing pneumonia, which suggests greater disease severity. The most common histological pattern was the indeterminate pattern, reflecting the peripheral characteristic of IPF. However, the fibrosis pattern showed high specificity and high negative predictive value. For CT scan patterns suggestive of IPF, the ROC curve showed that the best relationship between sensitivity and specificity occurred when five radiological alterations were present. Honeycombing was found to be strongly suggestive of IPF (p = 0.01). Conclusions: For ILDs, chest CT should always be performed, and TBB should be used in specific situations, according to the suspicion and distribution of lesions.

Keywords: Lung diseases, interstitial; Diagnosis, differential; Bronchoscopy.