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: 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.

Bronchoscopy with bronchoalveolar lavage, bronchial brush, and transbronchial biopsy are useful methods for the diagnosis of pulmonary diseases in patients infected with the human immunodeficiency virus (HIV). However, data on the accuracy of these techniques are conflicting. In order to estimate the sensitivity of the bronchoalveolar lavage, bronchial and transbronchial biopsy in pulmonary disease diagnosis in patients infected with HIV, the authors studied 71 consecutive patients, most of them with respiratory symptoms up to 15 days (58%) and radiologic signs of interstitial infiltrates (62%). The sensitivity was calculated taking as reference a constructed gold-standard, represented by the sum of all three techniques combined. Sensitivities for bronchoalveolar lavage, transbronchial biopsy, and bronchial brush were 86%, 43% and 5%, respectively. The association of bronchoalveolar lavage and transbronchial biopsy reached the sensitivity to 100%, reflecting how the gold-standard was constructed. The complication rate of the procedures was 3%. These results suggest that, in this population: (1) bronchoscopy with bronchoalveolar lavage, bronchial brush, and transbronchial biopsy are secure procedures with good diagnostic performance; (2) bronchoalveolar lavage alone has reached the highest sensitivity, whereas both bronchoalveolar lavage and transbronchial biopsy can be considered complementary techniques; (3) the association of bronchoalveolar lavage and transbronchial biopsy performed better than bronchoalveolar lavage alone; and (4) the use of bronchial brush in the sequence used in this protocol did not have any influence on the performance of diagnosis.

Keywords: Human immunodeficiency virus. Lung diseases. Diagnostic techniques. HIV. Lung infections.

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 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.

Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a new method for the diagnosis and staging of lung disease, and its use is increasing worldwide. It has been used as a means of diagnosing lung cancer in its initial stages, and there are data supporting its use for the diagnosis of benign lung disease. The aim of this study was to share our experience with EBUS-TBNA and discuss its diagnostic value. Methods: We retrospectively analyzed the results related to 159 patients who underwent EBUS-TBNA at our pulmonary medicine clinic between 2010 and 2013. We recorded the location and size of lymph nodes seen during EBUS. Lymph nodes that appeared to be affected on EBUS were sampled at least twice. We recorded the diagnostic results of EBUS-TBNA and (for cases in which EBUS-TBNA yielded an inconclusive diagnosis) the final diagnoses after further investigation and follow-up. Results: We evaluated 159 patients, of whom 89 (56%) were male and 70 (44%) were female. The mean age was 54.6 ± 14.2 years among the male patients and 51.9 ± 11.3 years among the female patients. Of the 159 patients evaluated, 115 (84%) were correctly diagnosed by EBUS. The diagnostic accuracy of EBUS-TBNA was 83% for benign granulomatous diseases and 77% for malignant diseases. Conclusions: The diagnostic value of EBUS-TBNA is also high for benign pathologies, such as sarcoidosis and tuberculosis. In patients with mediastinal disorders, the use of EBUS-TBNA should be encouraged, primarily because it markedly reduces the need for mediastinoscopy.

Keywords: Sarcoidosis; Tuberculosis, pulmonary; Lung neoplasms; Bronchoscopy; Mediastinoscopy; Endosonography.

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.

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.

We evaluated the diagnostic yield of fiberoptic bronchoscopy for the diagnosis of smear-negative pulmonary tuberculosis in patients treated at a referral hospital in Lima, Peru. Of the 611 patients who underwent the procedure, 140 (23%) were diagnosed with tuberculosis based on the analysis of BAL samples. Being young and being male were significantly associated with positive cultures. In addition, 287 patients underwent post-bronchoscopic sputum smear testing for AFB, the results of which increased the diagnostic yield by 22% over that obtained through the analysis of BAL samples alone. We conclude that the analysis of BAL samples and post-bronchoscopic sputum samples provides a high diagnostic yield in smear-negative patients suspected of having pulmonary tuberculosis.

Keywords: Tuberculosis, pulmonary/diagnosis; Bronchoscopy; Sputum.

Emphysema is a condition of the lung, characterized by the abnormal increase in the size of the airspace distal to the terminal bronchioles. Currently, emphysema is the fourth leading cause of death in the USA, affecting 14 million people. The present article describes the principal tools in the imaging diagnosis of emphysema, from the early days until the present. We describe traditional techniques, such as chest X-ray, together with the evolution of computed tomography (CT) to more advanced forms, such as high resolution CT, as well as three-dimensional CT densitometry and volumetric assessment.

Keywords: Emphysema; Radiology; Tomography, X-Ray computed; Radiography, thoracic.

Idiopathic pulmonary fibrosis (cryptogenic fibrosing alveolitis) is a progressive interstitia pulmonary disease of unknown etiology. Since Hamman's and Rich's (1944) reports, many studies have tried to find a histological marker for the correlation between prognosis and response to therapy. However, there are many doubts regarding pathogenesis. In addition, it is generally accepted that response to therapy is related to the relative degree of cellularity and fibrosis. The purpose of this study is to describe the results of inflammatory/exudative changes, fibrotic/reparative changes, and airway alterations, using a semi-quantitative method by independent evaluation of two pathologists, in 24 open lung biopsies with the diagnosis of idiopathic pulmonary fibrosis. Fourteen histological features were analyzed using the 0 to 5 scale for interstitial alterations and the 0 to 2 scale for the airway changes. There was significant interobserver agreement for all histological features with Kw (Kappa) variations between 0.47 and 0.92. There was significant disagreement only for septal inflammatory intensity analysis, suggesting that these features must be discussed by the pathologists. The semi-quantitative method assessment was effective.

Keywords: Idiopathic pulmonary fibrosis (IPF). Usual interstitial pneumonia (UIP). Semi-quantitative method assessment.

Objective: To evaluate the diagnostic performance of the rapid shallow breathing index (RSBI) in predicting extubation failure among adult patients in the intensive care unit and to determine the appropriateness of the classical RSBI cut-off value. Methods: This was a prospective study conducted in the adult intensive care unit of the Botucatu School of Medicine Hospital das Clínicas. The RSBI was evaluated in 73 consecutive patients considered clinically ready for extubation. Results: The classical RSBI cut-off value (105 breaths/min/L) presented a sensitivity of 20% and a specificity of 95% (sum = 115%). Analysis of the receiver operator characteristic (ROC) curve revealed a better cut-off value (76.5 breaths/min/L), which presented a sensitivity of 66% and a specificity of 74% (sum = 140%). The area under the ROC curve for the RSBI was 0.78. Conclusions: The classical RSBI cut-off value proved inappropriate, predicting only 20% of the cases of extubation failure in our sample. The new cut-off value provided substantial improvement in sensitivity, with an acceptable loss of specificity. The area under the ROC curve indicated that the discriminative power of the RSBI is satisfactory, which justifies the validation of this index for use.

Keywords: Adult; Intensive care; ROC curve; Ventilator weaning; Diagnosis; Respiration, artificial.