Background: The primary work-related lung disease in Brazil is silicosis. Its pathogenic agent is the dust of crystalline free silica (SiO2; silicon dioxide). The inflammatory process of silicosis is not yet well understood. Objective: To analyze, through immunologic laboratory evaluation, including nonspecific and specific immunity, the profile of IgG, IgM, IgA, C3, C4 and autoantibodies in the serum of workers, with or without silicosis, exposed to silica. Methods: Fifty-eight male workers were studied. All had been exposed to silica. Immunologic, radiologic and functional evaluations were made. The immunoglobulins IgG, IgA, and IgM, the complement system components C3 and C4, and the autoantibodies were assessed. Results: Chest X-rays were normal in 20 of the 58 workers and compatible with silicosis in 38. Among the 38 who were positive, IgG values were, on average, higher than in the group with normal X-rays (p < 0.05). There were no significant differences in average values of IgA, IgM, C3 or C4 (p > 0.05). The percentage of autoantibody positivity was higher in the silicosis group than in the group with normal X-rays. Conclusion: The increased levels of IgG in patients with silicosis constitutes an important discovery. It may represent continuity of the granulomatous reaction, even when the individual is no longer being exposed to silica. However, further studies are necessary in order to increase understanding of the mechanism involved in the silicosis immunologic process.

Keywords: Lung diseases. Silicosis. Occupational diseases. Immunoglobulins

Objective: To estimate the frequency of interstitial lung disease in a group of patients with progressive systemic sclerosis, and to describe the clinical, functional and radiological characteristics of the patients studied. Methods: Fifty-eight patients diagnosed with progressive systemic sclerosis were submitted to high-resolution computed tomography of the chest, pulmonary function tests and a blood test for anti-Scl 70 antibodies. Comparisons were drawn between patients with interstitial lung disease and those without. Logistic regression with multivariate analysis was used to identify factors predictive of interstitial lung disease. Results: Of the 58 patients evaluated, 51.7% presented interstitial lung disease on high-resolution computerized tomography scans. Dyspnea and cough were the most common symptoms (seen in 65.5% and 39.7%, respectively). Bronchiolectasis and honeycombing were the most common tomographic abnormalities (observed in 83.3% and 80%, respectively). When compared to individuals without interstitial lung disease, patients with the condition had a comparable frequency of pulmonary and extrapulmonary symptoms but presented progressive systemic sclerosis of longer duration, a higher frequency of crackling rales, higher rates of anti-Scl 70 positivity, lower vital capacity and reduced total lung capacity. Only forced vital capacity < 80% was found to be a predictor of interstitial lung disease. Conclusion: Interstitial lung disease was common in this group of patients with progressive systemic sclerosis. No correlation with symptoms was found, although interstitial lung disease was found to correlate with crackling rales and with anti-Scl 70 positivity. Nevertheless, only reduced forced vital capacity was found to be predictive of interstitial lung disease.

Objective: Various markers have shown promise as diagnostic markers and prognostic predictors in malignant mesothelioma (MM). Methods: Through morphometric and immunological studies of markers in stromal components (calretinin, CEA, Leu-M1 and thrombomodulin) and nuclear components (p53 and Ki-67), we evaluated post-diagnosis survival in 58 patients with MM. Results: The histologic pattern of the MM was typical in 50 cases and atypical in 8. Through immunohistochemistry, we confirmed 40 cases of mesothelioma and 11 cases of adenocarcinoma, although we were unable to classify 7 of the 8 cases presenting atypical histologic patterns. Cox multivariate analysis revealed that the risk factor for death was higher (476.2) among patients of advanced age, presenting the biphasic subtype and testing positive for components expressed at the nuclear level. Conclusion: The most useful immunohistochemical markers were was calretinin (for mesothelioma) and CEA (for adenocarcinoma). Immunohistochemical quantification of thrombomodulin facilitated the diagnosis of mesothelioma in patients testing positive for both calretinin and CEA. The most useful prognostic information was that provided by the routine histopathological analysis of the tumor type. It is of note that the combination of a mean age of 55 years and 30.5% immunohistochemical markers in nuclear components created a natural dividing point between patients in which survival was shorter than expected and those in which it was longer than expected. Therefore, histopathological analysis offers a powerful weapon with great potential to inform decisions regarding the use of adjuvant chemotherapy after surgical excision of a mesothelioma.

Keywords: Pleural neoplasms; Mesothelioma; Tumor markers, Biological; Carcinoembryonic antigen; Prognosis.

Objective: Silicosis is a pneumoconiosis characterized by fibrosis of the lung parenchyma caused by the inhalation of silica particles. Silica dust inhalation is associated with inflammation and induction of oxidative stress in the lungs. This oxidative stress affects telomeres, which are short tandem DNA repeats that cap the end of linear chromosomes. We aimed to determine whether telomere length (TL) correlates with silicosis or severity of silicosis in silica-exposed workers in Brazil. Methods: We included 200 men in southeastern Brazil: 100 with silicosis and 100 who had not been exposed to silica. We extracted DNA from buccal cells and assessed TL by multiplex quantitative polymerase chain reaction. Results: The median TL was significantly shorter in the patients with silicosis than in the unexposed controls (p < 0.0001), although it did not differ between the patients with simple silicosis and those with complicated silicosis (p = 0.961). We also found that, in patients with silicosis, TL was influenced by smoking (p = 0.034) and by a history of personal protective equipment use in the workplace (p = 0.002). Conclusions: Silica exposure appears to have an impact on TL, which was found to be shorter in patients with silicosis than in unexposed controls. Further studies are needed in order to confirm the impact that oxidative stress caused by silica inhalation has on telomeres.

Keywords: Silicosis; Oxidative stress; Inflammation; Telomere.

Silica is one of the main occupational agents associated with lung cancer. It is classified by the International Agency for Research on Cancer (IARC) as a Group 1 substance, i.e., carcinogenic for humans, since 1996. The objective of this paper is to report two cases of workers previously exposed to silica who developed lung cancer, seen in an out-patient clinic, focusing on important points of the current literature on the subject.

Introduction: Silicosis is the most prevalent pneumoconiosis in Brazil, with most of the registered cases occurring in the State of Minas Gerais. Although it is a preventable disease, silicosis is still epidemic in some areas. Objective: To describe the profile of workers seen at the Clinics Hospital of the Federal University of Minas Gerais. Patients and methods: 300 medical records of silica-exposed workers in different occupations, seen between 1989-2000, were reviewed. Clinical and occupational information, radiographic and spirometric data were analyzed. Statistical methods included univariate analyses with chi-square and t tests. Results and conclusion: The mean age of the exposed patients was 51 years, with mean exposure duration of 15.6 years. 126/300 (42%) were radiologically classified as cases of silicosis. Increasing grades of profusion were associated with lower spirometric indices and more frequent associations with tuberculosis and chronic airflow limitation. Most of the workers were regularly registered employees and the main occupational activity was mining, accounting for the exposure of 197 (66%) workers. Non-registered workers presented more severe radiological grades of silicosis, suggesting, possibly, worse conditions of silica exposure in this group of workers.

Objective: Silicosis is a pneumoconiosis characterized by fibrosis of the lung parenchyma caused by inhalation of silica particles. Genetic factors might play a role in the severity silicosis. We sought to evaluate the influence of polymorphisms in the ACE, FAS, FASLG, NOS2, IL1RN, FAM13A, TGFB1, and TNF genes on the severity of silicosis. Methods: Nine polymorphisms were genotyped by PCR in a sample of 143 patients with silicosis in the state of Rio de Janeiro, Brazil. Results: Fifty-seven patients (40%) were classified as having simple silicosis and 86 (60%) were classified as having complicated silicosis. The TT genotype of rs1800469 in the TGFB1 gene showed a protective effect for complicated silicosis (OR = 0.35; 95% CI, 0.14-0.92; p = 0.028) when compared with the other two genotypes (CC+CT). The polymorphic T allele of rs763110 in the FASLG gene (OR = 0.56; 95% CI, 0.31-0.99; p = 0.047), as well as a dominant model for the T allele (TT+CT: OR = 0.37; 95% CI, 0.15-0.96; p = 0.037), also showed a protective effect. When patients with simple silicosis despite having been exposed to silica for a longer time (> 44,229 hours) were compared with patients with complicated silicosis despite having been exposed to silica for a shorter time, the T allele of rs763110 in the FASLG gene (OR = 0.20; 95% CI, 0.08-0.48; p < 0.0001), as well as dominant and recessive models (OR = 0.06; 95% CI, 0.00-0.49; p = 0.01 and OR = 0.22; 95% CI, 0.06-0.77; p = 0.014, respectively), showed a protective effect against the severity of silicosis. Conclusions: It appears that rs1800469 polymorphisms in the TGFB1 gene and rs763110 polymorphisms in the FASLG gene are involved in the severity of silicosis. Given the lack of studies relating genetic polymorphisms to the severity of silicosis, these results should be replicated in other populations.

Keywords: Silicosis; Polymorphism, genetic; Genetic association studies; Cytokines.

Objective: To describe the characteristics of patients with influenza A (H1N1)-associated pneumonia treated at two hospitals in the region of Liguria, Italy, as well as to describe their treatment and outcomes. Methods: This was a prospective observational study including all patients older than 16 years of age with a confirmed diagnosis of influenza A (H1N1) who were admitted to Villa Scassi Hospital, in the city of Genoa, Italy, or to the Sestri Levante General Hospital, in the city of Sestri Levante, Italy, between September of 2009 and January of 2010. The primary outcome measure was mortality within 60 days after diagnosis. Secondary outcome measures were the need for mechanical ventilation and the length of hospital stay. Results: Of the 40 patients with a confirmed diagnosis of influenza A (H1N1), 27 presented pneumonia during the study period. The mean age of the 27 patients was 42.8 ± 14.8 years, and the mean length of hospital stay was 11.6 ± 8.2 days. Of the 27 patients, 20 had respiratory failure, 4 underwent invasive mechanical ventilation, and 5 underwent noninvasive ventilation. One patient had comorbidities, developed multiple organ failure, and died. Conclusions: During the influenza A (H1N1) pandemic, the associated mortality rate was lower in Italy than in other countries, and cases reported in the country typically had a milder course than did those reported elsewhere. Nevertheless, 9 of our cases (33%) rapidly evolved to respiratory failure, requiring mechanical ventilation.

Keywords: Pneumonia; Influenza A virus, H1N1 subtype; Respiratory insufficiency.

Some lung diseases are true diagnostic challenges due to their various clinical presentations. Actinomycosis is one such disease, potentially affecting various organs and systems. We report the case of a patient with pulmonary actinomycosis as a pseudotumor, which is usually only diagnosed by thoracotomy or thoracoscopy.

Keywords: Actinomycosis; Thoracic neoplasms; Bacterial infections and mycoses.