Although rare, rheumatoid pneumoconiosis, also known as Caplan's syndrome, can occur in workers exposed to silica, as well as in patients with silicosis, coal workers' pneumoconiosis or asbestosis. Prevalence is higher among patients with silicosis, despite the fact that it was originally described in coal workers with pneumoconiosis. The classical finding that defines this syndrome is that of rheumatoid nodules in the lungs, regardless of whether there are small rounded opacities suggestive of pneumoconiosis or large opacities consistent with massive pulmonary fibrosis, with or without clinical rheumatoid arthritis. We describe the case of a female patient with rheumatoid arthritis, diagnosed 34 years after 7 years of occupational exposure to silica at a porcelain plant. A chest X-ray showed circular opacities of 1-5 cm in diameter, bilaterally distributed at the periphery of the lungs. A CT-guided thoracic punch biopsy of one of those nodules revealed that it was rheumatoid nodule surrounded by a palisade of macrophages, which is typical of Caplan's syndrome. Aspects of diagnosis, classification and occurrence of this syndrome are discussed, emphasizing the importance of the occupational anamnesis of patients with rheumatoid arthritis and lung opacities on chest X-rays.

Keywords: Pneumoconiosis; Arthritis, rheumatoid; Caplan's syndrome; Silicosis.

Hard metal pneumoconiosis, first described in 1964, is a diffuse disease caused by the inhalation of cobalt particles. The disease can manifest as occupational asthma, interstitial disease or allergic alveolitis. We report the case of a young male, working as a tool sharpener, who presented with dry cough and progressive dyspnea for one year, as well as with spontaneous bilateral pneumothorax at admission. The diagnosis was confirmed by open lung biopsy.

Keywords: Lung diseases, interstitial; Pneumoconiosis; Pneumothorax.

Macrophage activation syndrome is a rare and potentially life-threatening disease. It occurs due to immune dysregulation manifested as excessive macrophage proliferation, typically causing hepatosplenomegaly, pancytopenia and hepatic dysfunction. Here, we report an unusual case of macrophage activation syndrome presenting as dyspnea, as well as (reported here for the first time) high resolution computed tomography findings of an excavated nodule, diffuse ground glass opacities and consolidations (mimicking severe pneumonia or alveolar hemorrhage). The patient was successfully treated with human immunoglobulin. We recommend that macrophage activation syndrome be considered in the differential diagnosis of respiratory failure. Rapid diagnosis and treatment are essential to achieving favorable outcomes in patients with this syndrome.

Keywords: Macrophage activation; Lymphohistiocytosis, hemophagocytic; Tomography, X-ray computed; Lung diseases, interstitial.

The authors present a 62-year-old male patient who had pulmonary nocardiosis with poor evolution. He also presented mental confusion, septic shock and a significant leukocytosis. Poor evolution happened even when sulfamethoxazole + trimethoprim replaced by ceftriaxone + clindamycin as an antibiotic therapy were used. Diagnostic methods, epidemiology and therapy of this infection are discussed and revised. The authors emphasize the importance of an early diagnosis, isolation in culture, and antibiogram examination of Nocardia ssp samples for therapeutic adapting.

Keywords: Pneumonia. Nocardia.

The use of immunobiological agents for the treatment of autoimmune diseases is increasing in medical practice. Anti-TNF therapies have been increasingly used in refractory autoimmune diseases, especially rheumatoid arthritis, with promising results. However, the use of such therapies has been associated with an increased risk of developing other autoimmune diseases. In addition, the use of anti-TNF agents can cause pulmonary complications, such as reactivation of mycobacterial and fungal infections, as well as sarcoidosis and other interstitial lung diseases (ILDs). There is evidence of an association between ILD and the use of anti-TNF agents, etanercept and infliximab in particular. Adalimumab is the newest drug in this class, and some authors have suggested that its use might induce or exacerbate preexisting ILDs. In this study, we report the first case of acute ILD secondary to the use of adalimumab in Brazil, in a patient with rheumatoid arthritis and without a history of ILD.

Keywords: Lung diseases, interstitial; Arthritis, rheumatoid; Antirheumatic agents; Antibodies, monoclonal, humanized/adverse effects.

Objective: To assess the risk factors for interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA) and to evaluate the association of ILD with the use of methotrexate as well as with joint disease activity. Methods: A retrospective, cross-sectional study conducted between March and December 2019 at a tertiary healthcare center, in a follow-up of RA patients who had undergone pulmonary function tests (PFT) and chest computed tomography. We evaluated the tomographic characteristics, such as the presence of ILD and its extension, as well as joint disease activity. Functional measurements, such as forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO), were also assessed. After this, a multivariate logistic regression analysis was applied in order to identify risk factors associated with ILD. Results: We evaluated 1.233 patients, of which 134 were eligible for this study. The majority were female (89.6%), with a mean age of 61 years old and with a positive rheumatoid factor (86.2%). RA-associated ILD (RA-ILD) was detected in 49 patients (36.6%). We found an association of RA-ILD with age == 62 year, male sex, smoking history and fine crackles in lung auscultation and a decreased DLCO. The indicators of being aged = 62 years old and having moderate or high RA disease activity were both independent factors associated with RA-ILD, with an odds ratio of 4.36 and 3.03, respectively. The use of methotrexate was not associated with a higher prevalence of ILD. Conclusion: Age and RA disease activity are important risk factors associated with RA-ILD. Methotrexate was not associated with the development of RA-ILD in the present study.

Keywords: Rheumatoid arthritis; Interstitial lung disease; Rheumatoid arthritis- associated interstitial lung disease.

Objective: To propose a new classification criterion for the differentiation between pleural exudates and transudates-quantifying total proteins in pleural fluid (TP-PF) and lactate dehydrogenase in pleural fluid (LDH-PF) exclusively-as well as to compare this new criterion with the classical criterion in terms of diagnostic yield. Methods: This was an observational, cross-sectional study with a within-subject design, comprising 181 patients with pleural effusion treated at two university hospitals in the state of Rio de Janeiro, Brazil, between 2003 and 2006. The diagnostic parameters included in the classical criterion were identified, as were those included in the new criterion. Results: Of the 181 patients, 152 and 29 were diagnosed with pleural exudates and pleural transudates, respectively. For the classical criterion, the sensitivity, specificity, and accuracy for the diagnosis of pleural exudates were, respectively, 99.8%, 68.6%, and 94.5%, whereas the corresponding values for the diagnosis of pleural transudates were 76.1%, 90.1%, and 87.6%. For the new criterion (cut-off points set at 3.4 g/dL for TP-PF and 328.0 U/L for LDH-PF), the sensitivity, specificity, and accuracy for the diagnosis of exudates were, respectively, 99.4%, 72.6%, and 99.2%, whereas the corresponding values for the diagnosis of transudates were 98.5%, 83.4%, and 90.0%. The accuracy of the new criterion for the diagnosis of pleural exudates was significantly greater than was that of the classical criterion (p = 0.0022). Conclusions: The diagnostic yield was comparable between the two criteria studied. Therefore, the new classification criterion can be used in daily practice.

Keywords: Pleural effusion/diagnosis; Pleural effusion/classification; Exudates and transudates.

A case is presented of a 36 year-old woman, with metastatic lung choriocarcinoma with atypical clinical and radiological presentation. The finding of pulmonary hypertension indicated the possibility of pulmonary thromboembolism, still, the definitive diagnosis and cause of pulmonary embolism were done in the autopsy. The authors discuss the manners of choriocarcinoma metastasis presentation, its repercussions and the latent period which may exist until it presents evidence of neoplasm.

Keywords: Choriocarcinoma. Pulmonary embolism.

Objective: To identify fibromyalgia syndrome in patients with sleep disordered breathing. Method: We studied 50 patients seeking treatment at a sleep disorder clinic for snoring, apnea and excessive daytime sleepiness. Sleep disordered breathing was diagnosed through the use of polysomnography. To diagnose fibromyalgia syndrome, patients were evaluated in accordance with the criteria established by the American College of Rheumatology. Results: Of the 50 patients, 32 were male. The mean (± standard deviation) age of the group was 50 ± 12 years. The mean body mass index was 29.7 ± 5.6 kg/m2. The mean apnea-hypopnea index was 36 ± 29 attacks of apnea or hypopnea per hour of sleep. Of the 18 women and 32 men evaluated, 9 and 2, respectively, met the American College of Rheumatology criteria for fibromyalgia syndrome. Conclusion: Considering the fact that the prevalence of fibromyalgia syndrome in the general population is 0.5% for men and 3.4% for women, the more than ten-fold higher proportion of fibromyalgia cases seen in this sample supports the hypothesis that there is an association between sleep disordered breathing and fibromyalgia syndrome.

Keywords: Respiration disorders/complications; Fibromyalgia/complications; Sleep apnea, obstructive; Polysomnography

A case of a patient with Pancoast's syndrome associated with acquired immunodeficiency syndrome is reported. This association is rare and Kaposi's sarcoma and non-Hodgkin lymphoma are the most recurrent tumors in AIDS. The patient was an IV drug user and was admitted to the hospital for diagnosis of apex lung mass with signs of Pancoast's syndrome. HIV serology was positive and pathology of lung mass showed non-small cell lung cancer.

Keywords: Pancoast's syndrome. HIV. Bronchogenic carcinoma. Lung neoplasms. Acquired immunodeficiency syndrome.

Objective: The emergence of tuberculosis/HIV co-infection and the increase in the number of cases of infection with nontuberculous mycobacteria (NTM) require rapid laboratory test results in the isolation and identification of mycobacteria. The objective of this study was to evaluate the identification of mycobacteria by means of gene probes in comparison with that obtained using classical biochemical methods. Methods: Between 2002 and 2004, 178 mycobacterial cultures, all testing positive for acid-fast bacilli, were analyzed. Samples were obtained from clinical specimens of patients with respiratory symptoms or with clinical suspicion of pulmonary tuberculosis/mycobacteriosis who were treated in the greater metropolitan area of Santos. Results: The gene probe identified 137 samples (77%) as Mycobacterium tuberculosis complex and 41 (23%) as NTM. Discordant results between the methods (3%) were obtained only in the year of implementation (2002). When comparing the methods, the sensitivity, specificity, positive predictive value and negative predictive value of the gene probe method were 98%, 93%, 98% and 93%, respectively. Conclusions: Despite the cost, the identification of mycobacteria using the molecular technique is faster: maximum 3 h vs. 28-30 days for classical methods. The use of gene probes is a validated molecular technique. It is fast, easy to use and readily available on the market. It has high specificity and sensitivity, which justifies its implementation and routine use in referral laboratories, since it facilitates the diagnosis providing agile clinical interventions.

Keywords: Mycobacterium tuberculosis; Tuberculosis/diagnosis; Mycobacterium/classification; DNA probes.

Scimitar syndrome is rare, but knowledge about it is important to pediatricians and pneumologists. X-ray can suggest diagnosis, but the interpretation can be wrong. If a diagnosis is made, further anomalies must be investigated with echocardiography and angiography, even if he patient is asymptomatic. This child showed evidence of pulmonary hypertension and required surgery. Postoperative evolution was excellent.

Keywords: Scimitar syndrome. Surgery. Pulmonary disease (specialty). Diagnosis.

Castleman's disease is a rare lymphoproliferative disorder, with focal or systemic lymph node involvement, which rarely affects the lung parenchyma. We report the case of an asymptomatic immunocompetent male patient who had the rarest histological variant of the disease, a nodular parenchymal presentation. The patient underwent lobectomy, and the postoperative evolution was favorable. In the last 10 years, there have been only five reports of Castleman's disease presenting as a solitary pulmonary nodule. This case underscores the fact that Castleman's disease, albeit rare, should be included in the differential diagnosis of pulmonary nodules.

Keywords: Giant lymph node hyperplasia; Lymphoproliferative disorders; Solitary pulmonary nodule.

Cow milk allergens are the first antigens children have contact with. The symptoms, which are frequently multi-systemic, may be related to the gastrointestinal tract, to the skin and, more rarely, to the respiratory tract. Objective: To describe some clinic and epidemiological characteristics of children who have cow milk allergy and present respiratory symptoms. Patients and method: This retrospective study included 17 children who presented respiratory problems immediately after ingesting cow milk, showed no symptoms as cow milk was excluded from their diets for a period of 4 to 6 weeks, and presented recurrent symptoms as cow milk was reintroduced into their diet in a hospital environment. Results: No difference was observed between genders. Family atopic antecedents were present in 14 of the 17 children. Mean exclusive breast-feeding period was 2.9 months and the onset of symptoms occurred at an average of 3.6 months. Eight of the ten tests conducted to evaluate immediate cutaneous hypersensitivity to cow milk were positive. Clinical manifestations observed were: wheezing infants (9), asthma (5), repetition otitis (2), selective IgA deficiency related to wheezing and allergic rhinoconjunctivitis (1). Conclusion: Regarding wheezing infants, cow milk allergy should be included as a differential diagnosis and exclusive breast-feeding should be stimulated in cases of atopic family antecedents. However, a precise diagnosis is vital to prevent unnecessary food deprivation.

Keywords: Milk hipersensitivity. Milk substitutes. Respiratory signs and symptoms. Respiratory diseases.

Objective: To determine whether simple diagnostic methods can yield relevant disease information in patients with rheumatoid arthritis (RA). Methods: Patients with RA were randomly selected for inclusion in a cross-sectional study involving clinical evaluation of pulmonary function, including pulse oximetry (determination of SpO2, at rest), chest X-ray, and spirometry. Results: A total of 246 RA patients underwent complete assessments. Half of the patients in our sample reported a history of smoking. Spirometry was abnormal in 30% of the patients; the chest X-ray was abnormal in 45%; and the SpO2 was abnormal in 13%. Normal chest X-ray, spirometry, and SpO2 were observed simultaneously in only 41% of the RA patients. A history of smoking was associated with abnormal spirometry findings, including evidence of obstructive or restrictive lung disease, and with abnormal chest X-ray findings, as well as with an interstitial pattern on the chest X-ray. Comparing the patients in whom all test results were normal (n = 101) with those in whom abnormal test results were obtained (n = 145), we found a statistically significant difference between the two groups, in terms of age and smoking status. Notably, there were signs of airway disease in nearly half of the patients with minimal or no history of tobacco smoke exposure. Conclusions: Pulmonary involvement in RA can be identified through the use of a combination of diagnostic methods that are simple, safe, and inexpensive. Our results lead us to suggest that RA patients with signs of lung involvement should be screened for lung abnormalities, even if presenting with no respiratory symptoms.

Keywords: Arthritis, rheumatoid; Lung diseases, interstitial; Spirometry; Radiography, thoracic; Airway ob-struction.

Rheumatoid arthritis (RA) is an autoimmune inflammatory and heterogeneous disease that affects several systems, especially the joints. Among the extra-articular manifestations of RA, pleuropulmonary involvement occurs frequently, with different presentations, potentially in all anatomic thoracic compartments, and may determine high morbidity and mortality. The most common pleuropulmonary manifestations in patients with RA include interstitial lung disease (ILD), pleural disease, pulmonary arterial hypertension, rheumatoid lung nodules, airway disease (bronchiectasis and bronchiolitis), and lymphadenopathy. Pulmonary hypertension and ILD are the manifestations with the greatest negative impact in prognosis. HRCT of the chest is essential in the evaluation of patients with RA with respiratory symptoms, especially those with higher risk factors for ILD, such as male gender, smoking, older age, high levels of rheumatoid factor, or positive anti-cyclic citrullinated peptide antibody results. Additionally, other etiologies that may determine tomographic pleuropulmonary manifestations in patients with RA are infections, neoplasms, and drug-induced lung disease. In these scenarios, clinical presentation is heterogeneous, varying from being asymptomatic to having progressive respiratory failure. Knowledge on the potential etiologies causing tomographic pleuropulmonary manifestations in patients with RA coupled with proper clinical reasoning is crucial to diagnose and treat these patients.

Keywords: Lung diseases, interstitial; Lung diseases; Pleural diseases; Pulmonary arterial hypertension; Arthritis, rheumatoid; Tomography.