Diagnosis Of Silicosis Research Articles

The levels and clinical significance of serum leptin and transforming growth factor beta1 in silicosis patients

Objective: To investigate the levels and clinical significance of serum leptin and transforming growth beta 1 (TGF-β1) in silicosis patients. Methods: A total of 52 patients with silicosis (already identified as occupational diseases) were enrolled in the Department of Respiratory and Critical Disease Medicine, the First Hospital of Shanxi Medical University from June 2018 to July 2019. These patients were regarded as silicosis group. They were divided into 25 patients with first stage silicosis, 22 patients with second stage silicosis and 5 patients with third stage silicosis. At the same time, 30 patients with no history of dust exposure in the same period of physical examination were selected as control group. Serum leptin and TGF-β1 levels were measured by enzyme-linked immunosorbent assay in all investigators. At the same time, the comparison and correlation analysis between groups were carried out, and the diagnostic value was judged by receive operating characteristic (ROC) curve. Results: The serum levels of leptin and TGF-β1 in silicosis patients were higher than those in the control group, the differences were statistically significant (P<0.05) . The serum levels of leptin in patients with second stage and third stage silicosis were higher than those in the control group and first stage, the differences were statistically significant (P<0.05) . Serum levels of TGF-β1 in all stage silicosis patients were higher than those in the control group, and third stage silicosis was higher than first stage, the differences were statistically significant (P<0.05) . There was a positive correlation between serum levels of leptin and TGF-β1 in silicosis group (r(s)=0.400, P<0.05) . The ROC area of leptin and TGF-β1 combined to predict silicosis was 0.826, with the sensitivity and specificity were 73.10% and 80.00%. Conclusion: The levels of serum leptin and TGF-β 1 are related to different stages of silicosis, and the combined detection of leptin and TGF-β 1 can assist the diagnosis of silicosis.

Clinical significance of CC16 and IL-12 in bronchoalveolar lavage fluid of various stages of silicosis.

Identification of novel biomarkers for silicosis could be helpful for disease diagnosis and pathophysiological mechanism exploration. Our study aims to investigate the Clara cell secretory 16-kd protein (CC16) and interleukin-12 (IL-12) levels in bronchoalveolar lavage fluid (BALF) in patients with silicosis at various stages. The enzyme-linked immunosorbent assay (ELISA) double antibody sandwich method was used to determine the CC16 and IL-12 in BALF levels from 79 patients with silicosis of various stages. Correlation analyses were performed between CC16 and IL-12 levels, and lung function and cytological counts in patients with silicosis at various stages. There were no significant differences in the BALF recovery volume, the number of cells, percentages of macrophages and lymphocytes in the alveolar lavage fluid of patients with silicosis in different stages (P>0.05); the percentage of neutrophils in stage I and stage II were higher than the control group (P<0.05) with statistically significant differences. The CC16 in BALF levels in stage I and II silicosis groups lower than the control group and stage III silicosis group with statistically significant differences (P<0.05), whereas CC16 levels in stage II silicosis group are higher than the stage I group (P<0.01). The IL-12 levels were higher than the control group (P<0.01), and the IL-12 levels in stage II and III silicosis group was higher than the stage I silicosis group (P<0.01). With the increase of the length of dust service, the CC16 and IL-12 levels decreased and showed a positive correlation between these indexes (correlation coefficient r=0.559, P<0.01). In addition, CC16 silicosis patient levels were positively correlated with FEV1/FVC and VCmax (r=0.242, 0.257; both P<0.05); IL-12 levels were negatively correlated with FEV1 and VC max (r=-0.250, -0.483; both P<0.05). The CC16 and IL-12 levels may have a specific reference value for the early diagnosis of silicosis and the assessment of lung function.

Lung function and functional exercise capacity in underground semi-precious stone mineworkers.

Semi-precious stone mining may cause occupational lung disease. The impact of inhaling silica on workers' exercise capacity has only been partially studied. To study lung function, exercise capacity, and identify factors associated with functional impairment. In a cross-sectional study of 193 current miners from Ametista do Sul, Rio Grande do Sul, Brazil, medical and occupational data were collected. The diagnosis of silicosis was established by the history of dust exposure and chest radiographic findings. All workers performed a spirometry and a 6-minute walk test (6MWT). Of the sample 51 (26.4%) had silicosis. Time working in mine was 14.7±8.7 years. Spirometry showed a normal, restrictive or obstructive ventilatory pattern in 75.1 %, 13 % and 9.3 % of the workers, respectively. The diagnosis of silicosis and length of time working in mining negatively affected lung function, although exercise capacity was preserved. In the multivariate analysis, time working in mining, diagnosis of silicosis and education remained significant for forced expiratory volume in one second (FEV1; r = 0.60; r2 = 0.36; p < 0.001) and age and height for distance in 6MWT (r = 0.66; r2 = 0.43; p < 0.001). Our results show impaired lung function and preserved exercise capacity in current mineworkers exposed to silica. Length of time working in mining, presence of silicosis and lower education were factors associated with reduced lung function.

Pneumotoraks Bilateral dan Transaminitis Non Spesifik pada Silikosis

Background: Silicosis is a fibrosis in the lung caused by inhalation, retention, and reaction to crystalline silica. The prevalence rate is potentially increasing throughout the world. Cases of bilateral spontaneous pneumothorax and transaminitis due to complications of silicosis are very rare. In this case, the patient was presented with bilateral secondary spontaneous pneumothorax as well as in the development of the diagnosis of silicosis, liver dysfunction, and pneumonia. Case: A 36-year-old male was admited to hospital with shortness of breath, the patient was once stone artisans for 7 years, rarely using PPE. Bilateral pneumothorax was established based on the results of clinical and radiological examinations. HRCT showed that it supported silicosis, left fluidopneumothorax, and right pneumothorax. Bronchoscopy was not possible due to the incompatible conditions and subsequently the patient was examined for silica levels from both plueral fluid with significant pleural silica. Summary: Diagnosis of pulmonary silicosis was done by clinical, radiological, and silica analysis of bronchial rinses, but certain conditions of silica could be found from pleural fluid. Silicosis therapy with complications until recently is only symptomatic, definitive therapy has not been found. Silicosis complications can be from pneumothorax bilateral (rarely), tuberculosis, transaminitis, and pneumonia. Conclusion: Pulmonary silicosis can be found from pleural fluid when the amount is large enough, fibrosis and extensive lung damage occurred. Silicosis can have an impact on pneumothorax, liver disorders, pneumonia, tuberculosis, and respiratory problems.

Screening Strategy for Early Diagnosis of Silicosis in At-Risk Populations in Oklahoma

Screening Strategy for Early Diagnosis of Silicosis in At-Risk Populations in Oklahoma

Establishment of a CT image radiomics-based prediction model for the differential diagnosis of silicosis and tuberculosis nodules

Objective: To establish a CT image radiomics-based prediction model for the differential diagnosis of silicosis and tuberculosis nodules. Methods: A total of 53 patients with silicosis and 89 patients with tuberculosis who underwent routine CT scans in Suzhou Fifth People's Hospital from January to August, 2018 were enrolled in this study. AK/ITK software was used to segment the images to obtain 139 silicosis lesions and 119 tuberculosis lesions. For each lesion image, 396 features were extracted, and feature dimension reduction was applied to select the most characteristic feature subset. Support vector machine (SVM) , feedforward back propagation neural network (FNN-BP) , and random forest (RF) were implemented using R software (Rstudio V1.1.463) , and the algorithm that achieved the largest area under of the receiver operating characteristic (ROC) curve (AUC) was selected as the final prediction model. Results: RF was the best prediction model for the differential diagnosis of silicosis and tuberculosis nodules, with an accuracy of 83.1%, a sensitivity of 0.76, a specificity of 0.9, and an AUC of 0.917 (95% confidence interval: 0.8431-0.9758) . RF had a significantly larger AUC than SVM and FNN-BP (P<0.05) . Conclusion: CT image-based RF prediction model can be used to differentially diagnose silicosis and tuberculosis nodules.

The effects of long-term exposure to silica dust on serum CC16 and KL-6 levels

Objective: To investigate the effects of long-term exposure to silica dust on serum CC16 and KL-6 levels. Methods: The patients with stage I silicosis who were hospitalized in our hospital from April 2016 to April 2017 were treated as silicosis group. The silica dust exposed workers without silicosis who were taken the physical examination in our hospital were taken as a dust-exposed group. The healthy control group comes from in the same period of community physical examination did not touch the dust. The levels of CC16 and KL-6 in serum of all subjects were determined by enzyme-linked immunosorbent assay (ELISA) , and the levels of CC16 and KL-6 in serum were compared in three groups. Results: Compared with the control group, the serum levels of CC16 in the silicosis group (P<0.01) and the dust-exposed group (P<0.01) were significantly lower. Compared with the control group, the level of serum KL-6 in the silicosis group was significantly decreased (P<0.01) compared with the control group, while the level of KL-6 in the serum of the dust-exposed group was significantly increased (P<0.01) . The ROC area of CC16 for diagnosis of silicosis was 0.92 (P<0.01) , with a sensitivity of 81.37%, specificity of 92.63% and Kappa value of 0.74. Conclusion: Long-term exposure to silica dust may lead to a decrease in serum CC16 levels. Reduced serum CC16 levels may be useful in identifying the diagnosis of silicosis.

Silicosis: Diagnosis and Medicolegal Implications.

Despite well-publicized sources of occupational hazard, silicosis continues to threaten industrial workers in the United States. We performed a retrospective search of the University of Wisconsin electronic pathology database to retrieve autopsy cases of silicosis and collaborated with the Wisconsin Department of Health Services to obtain statewide epidemiologic data regarding silicosis morbidity/mortality since 2003. Three silicosis autopsy cases were retrieved: all were men with≥30years of occupational crystalline silica exposure and similar histologic features of collagenous pulmonary nodules with admixed refractile particles. Overall, our state exceeds the national rate of silicosis-related hospitalizations and mortality, that is, 10.1 hospitalizations per million WI residents versus 1.2 nationally and 1.2 deaths per million WI residents versus 0.4 nationally. Surveillance is crucial to identify emerging occupational hazards and protect workers. A diagnosis of silicosis must be carefully considered at autopsy since it carries substantial implications for worker's compensation, compensatory losses, and employer liability.

Computed tomography in diagnosis of silicosis

Respiratory system diseases are one of the main problems in contemporary occupational medicine and exceed one fifth of all occupational diseases. Objective of the review was search and analysis of literature on diagnosis of silicosis as an important occupational disease of respiratory organs, by computed tomography and high-resolution computed tomography, from evidence-based medicine viewpoint.

The Burden of Silicosis in Michigan: 1988-2016.

Exposure to respirable crystalline silica causes silicosis, a preventable, progressive occupational lung disease. A more rigorous occupational health standard for silica could help protect silica-exposed workers. To describe trends over 29 years of silicosis surveillance in Michigan. Michigan law requires the reporting of silicosis. We confirmed the diagnosis of silicosis in reported cases using medical questionnaires, review of medical records, and chest radiographs. The Michigan Occupational Safety and Health Administration (OSHA) conducted enforcement inspections at the workplaces of the silicosis cases, including air monitoring for silica and evaluation of workplace medical surveillance programs. The Michigan surveillance program identified 1,048 silicosis cases from 1988 to 2016, which decreased from 620 during 1988-1997, to 292 during 1998-2007, to 136 during 2008-2016. The cumulative incidence rate of silicosis decreased from 3.7 to 1.4 to 0.7 cases per 100,000 men 40 years of age and older in Michigan over the same three periods. African Americans had a higher cumulative incidence rate of silicosis, with 6.0 cases per 100,000 African American men 40 years of age and older in Michigan compared with 1.2 cases per 100,000 white men 40 years of age and older in Michigan. The cases identified had severe disease; 59% had progressive massive fibrosis or category 2 or 3 small opacities per B-reading classification of the chest radiograph. Seventeen percent reported ever having active tuberculosis. On spirometry, 76% of ever smokers and 72% of never smokers demonstrated either a restrictive or an obstructive pattern. Most (65%) had not applied for workers' compensation benefits; the percentage who applied for benefits decreased from 42% to 28-16% over the three periods. Thirty-four of 55 (62%) workplace inspections found exposures above the new OSHA 50 μg/m3 respirable crystalline silica permissible exposure limit, and only 11% of inspected companies screened their workers for silicosis. Adults with confirmed cases of silicosis have advanced disease and morbidity. Most are not using workers' compensation to pay for their care. The new OSHA silica standard, which lowers the permissible exposure limit for silica and requires medical monitoring to identify workers with silicosis, will help reduce the burden of silica exposure. It is critical for pulmonologists to be vigilant to recognize and manage this preventable occupational lung disease.

The clinical application value of ultrasound-guided percutaneous lung biopsy in the diagnosis of peripheral lung lesions of silicosis

Objective To determine the clinical application value of percutaneous lung biopsy guided by ultrasound in the diagnosis of peripheral lung lesions of silicosis. Methods Experimental silicosis was produced in rabbits by the intratracheal administration of silica with non-exposure method. Imaging changes were observed in 36 rabbits on 60 days after intratracheal instillation of silica. To contrast with CT results, percutaneous lung biopsy of peripheral lesions was guided by ultrasound. The success rate of sufficient material, the diagnosis rate of coincidence between biopsy and pathology, and the incidence of complications were calculated. The biopsy with sufficient material, biopsy findings coincided with pathological results and no complications were defined as strictly success of the puncture. The baseline data and monitoring index were compared between successful biopsy group and unsuccessful biopsy group. Each rabbit was intravenously administrated by 10 000 U of heparin for the antiocoagulation and sacrificed by fast injection of 10% KCl through jugular vein catheterization. Specimens from lung tissue were collected and stained with hematoxylin-eosin. Pathological changes of lung tissue were observed through an optical microscope. Results Of 36 silicosis rabbits, peripheral lung lesions of silicosis were observed in 30 rabbits. Biopsy procedures were performed with ultrasound guidance in 30 rabbits. The total success rate of biopsy was 70% (21/30). The success rate of sufficient material was 93% (28/30), the diagnosis rate of coincidence between biopsy and pathology 86%(24/28), and the incidence of complications was 10% (3/30) respectively. Compared with failure group, peripheral lesions in successful biopsy group were bigger in size, closer to the chest wall, and lower respiratory rate, the difference was statistically significant (P 0.05). The pathological results showed typical silicosis nodules. Silica-exposed rabbit also showed signs of vascular remodeling with pulmonary artery muscularization, vascular occlusion, and medial thickening. Conclusions Ultrasound-guided percutaneous lung biopsy is an effective and safe method in peripheral lung lesions of silicosis. It can serve as an important technical means to monitor the evolution of silicosis lesions and provide reference for the diagnosis of silicosis. Observation of small vascular changes in silicosis nodules by lung biopsy is helpful for clinical intervention treatment. Key words: Ultrasonography; Silicosis; Vascular remodeling; Biopsy, needle

EBUS-TBNA is Sufficient for Successful Diagnosis of Silicosis with Mediastinal Lymphadenopathy.

Silicosis is an occupational lung disease resulting from inhalation of respirable crystalline silica. Recently, an international silicosis epidemic has been noted among artificial stone workers. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is currently used for patients with unexplained lymphadenopathy. Since silicosis may present with prominent lymphadenopathy, the diagnostic yield of EBUS-TBNA in diagnosing silicosis was evaluated. Twenty-eight patients with suspected silicosis referred for outpatient evaluation in three large tertiary hospitals were evaluated. Patients with mediastinal lymphadenopathy underwent EBUS-TBNA, while others underwent TBB and/or video-assisted thoracoscopic surgery (VATS). Eleven patients with mediastinal lymphadenopathy (39%) were evaluated using EBUS-TBNA. The diagnosis was accurate in all cases, demonstrating silica particles under polarized light, with no complications. Among the remaining patients, TBB was only 76% diagnostic, therefore requiring VATS. EBUS-TBNA is a useful and sufficient tool to diagnose silicosis in patients with mediastinal lymphadenopathy along compatible exposure histories.

Outbreak Investigation of Silicosis in Saraburi Province, Thailand

Background: The staff of the Office of Disease Prevention and Control 4, Saraburi, Department of Disease Control, Ministry of Public Health, Thailand analyzed the data of 28 cases of diagnosed silicosis (J62.8) whose data were reported to the Health Data Center in Saraburi province, Thailand. Thus, its staff in collaboration with the staff of the Bureau of Occupational and Environmental Diseases, Department of Disease Control, Ministry of Public Health, Thailand formed the outbreak investigation team for this epidemiological outbreak of silicosis in Saraburi province, Thailand and operated from May 15, 2017 to May 17, 2017. Objective: 1. To confirm the diagnosis of Silicosis. 2. To find the causes of Silicosis. 3. To advice the health-care issues for Silicosis prevention to all patients diagnosed of Silicosis including high-risk populations of Silicosis Methodology 1. Meeting with stakeholders at Saraburi Hospital. This aimed to examine diagnostic Criteria from medical records in Saraburi Hospital and to define the definition of patients and suspected patients with Silicosis as well as organizing an investigation team. 2.Investigated suspected patients with Silicosis by using the clinical criteria which was provided by Saraburi Provincial Public Health Office, the Office of Disease Prevention and Control 4, Saraburi, Saraburi Hospital as well as the Health Promoting Hospitals.3.Meeting of a summarizing the investigation and root cause analysis regarding Silicosis with the Bureau of Occupational and Environmental Diseases, Saraburi Provincial Public Health Office and the Office of Disease Prevention and Control 4, Saraburi at Saraburi Hospital as well as planning for a surveillance system. Results: From analysis of 28 cases registered in Health Data Center, Saraburi province, Thailand by the outbreak investigation team, there were one case with no data availability, three cases with non-classification of suspected Silicosis, and 24 cases of suspicion criteria. Out of 24 Silicosis suspected cases, 8 cases were unable to follow up due to their homes being out of the Health Inspection Region 4, one case died of Nocardia species infection, one case of not being occupational cause, and one case of refuse to provide personal health data. Thus, only 13 cases were eligible for study. Of 13 cases, 12 cases were diagnosed of chronic Silicosis whereas one case was not compatible with the diagnostic criteria. Conclusion: As a result of the investigation of 13 cases, 12 cases were diagnosed as chronic silicosis. The main cause of silicosis in this study population was receiver, whereas the secondary causes were source and passage.

Regulation of TLR4 in silica-induced inflammation: An underlying mechanism of silicosis.

Silicosis is an incurable lung disease affecting millions of workers in hazardous occupations. It is caused by chronic exposure to the dust that contains free crystalline silica. Silica-induced lung damage occurs by several main mechanisms including cell death by apoptosis, fibrosis and production of cytokines. However, the signal pathways involved in these mechanisms are not fully characterized. In this study, the toll-like receptor 4 (TLR4)-related signal pathway was examined in silica-treated U937-differentiated macrophages. The expression level of TLR4 was measured by both quantitative PCR and Western blot. Confirmation of the involvement of MyD88/TIRAP and NFκB p65 cascade was performed by Western blot. The secretion of cytokines IL-1β, IL-6, IL-10 and TNFα was measured by enzyme-linked immunosorbent assay. Our results showed that TLR4 and related MyD88/TIRAP pathway was associated with silica-exposure in U937-differentiated macrophages. Protein expression of TLR4, MyD88 and TIRAP was upregulated when the U937-differentiated macrophages were exposed to silica. However, the upregulation was attenuated when TLR4 inhibitor, TAK-242 was present. At different incubation times of silica exposure, it was found that NFκB p65 cascade was activated at 10-60 minutes. Release of cytokines IL-1β, IL-6, IL-10 and TNFα was induced by silica exposure and the induction of IL-1β, IL-6 and TNFα was suppressed by the addition of TAK-242. In conclusion, our study demonstrated that TLR4 and related MyD88/TIRAP pathway was involved in silica-induced inflammation in U937-differentiated macrophages. Downstream NFκB p65 cascade was activated within 1 hour when the U937-differentiated macrophages were exposed to silica. The better understanding of early stage of silica-induced inflammatory process may help to develop earlier diagnosis of silicosis.

The role of mediastinoscopy in the diagnosis of non-lung cancer diseases.

BackgroundMediastinoscopy is a good method to evaluate mediastinal lesions. We sought to determine the current role of mediastinoscopy in the investigation of non-lung cancer patients with mediastinal lymphadenopathy.Materials and methodsWe retrospectively reviewed clinical parameters (age, gender, histological diagnosis, morbidity, mortality) of all patients without lung cancer who consecutively underwent mediastinoscopy in Hospital of Faculty of Medicine of Dicle University between June 2003 and December 2016.ResultsTwo-hundred twenty nine patients without lung cancer who underwent mediastinoscopy for the pathological evaluation of mediastinum during the study period were included. There were 156 female (68%) and 73 male (32%) patients. Mean age was 52.6 years (range, 16 to 85 years). Mean operative time was 41 minutes (range, 25 to 90 minutes). Mean number of biopsies was 9.3 (range, 5 to 24). Totally, 45 patients (19.6%) had previously undergone a nondiagnostic bronchoscopic biopsy such as transbronchial needle aspiration or endobronchial ultrasound-guided transbronchial needle aspiration. Mediastinoscopy was diagnostic for all patients. Diagnosis included sarcoidosis (n=100), tuberculous lymphadenitis (n=66), anthracosis lymphadenitis (n=44), lymphoma (n=11) metastatic carcinoma (n=5), and Castleman’s disease (n=1); there was a diagnosis of silicosis in one patient and tymoma in one patient. Neither operative mortality nor major complication developed. The only minor complication was wound infection which was detected in three patients.ConclusionAlthough newer diagnostic modalities are being increasingly used to diagnose mediastinal diseases, mediastinoscopy continues to be a reliable method for the investigation of mediastinal lesions.

Guideline (S2k, AWMF) of the Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin and the Deutsche Gesellschaft für Arbeitsmedizin und Umweltmedizin "Diagnostics and Expert Opinion in the Occupational Disease No. 4101 Silicosis (Including Coal Worker's Pneumoconiosis)"

During the last 1.5 years an update of the guideline on silicosis was made by an interdisciplinary working group. New medical and scientific knowledge and the experience in expert opinion practice were taken into account.By preparing the initial guideline in 2010 standardization of diagnostics and adaption of the "Moers convention" which was not based on medical knowledge was in the focus, whereas the current update deals with fine emendation and extension, especially of the compensation rate (adaption with the Reichenhall recommendation).The diagnosis of silicosis (including mixed dust pneumoconiosis) is based on a detailed occupational history, and predominantly on the typical radiological findings. However, at initial diagnosis the standardized LD-HRCT takes an important role because of its high sensitivity and specificity. Exceptional cases are those with characteristic findings in chest X-ray follow-up. Correspondingly, it is mentioned in the guideline: "The standardized appraisal of the Low-Dose-Volume HRCT requires application of the CT classification (ICOERD, International Classification of Occupational and Environmental Respiratory diseases). In order to diagnose silicosis in CT scan opacities with sharp borders in both central upper lung fields and their circumferencies have to be documented. By comparing with ILO standard radiographs at least profusion category 1 in the right and left upper lung fields has to be reached (total profusion category 2)."The pathologic minimal requirement for the diagnosis of silicosis which has undergone controversial discussion has now also been defined. Corresponding to Hnizdo et al. 2000 it is now mentioned: "Finding of less than 5 silicotic granuloma per lung lobe by palpation is regarded as insignificant." This is a convention and not a threshold based on detailed medical scientific and statistical studies; it is based on extended experience in the South African gold mines.This guideline also deals with silicotic hilar (and sometimes mediastinial) lymph nodes; according to the guideline working group they do not closely correlate with the degree of pulmonary involvement. Extended conglomerating and enduring lymph-node processes may lead to dislocation of the hili with impairment of large bronchi and vessels. Shell-like calcifications dominating in the periphery of lymph nodes produce so-called egg-shell hili.The paragraph on exercise testing is now extended: if neither ergometry nor spiroergometry can be performed a 6 minute walking test by measuring oxygen saturation should be done.Furthermore, in individual expert opinion examinations right heart catheterization (the patient is not obliged to give informed consent) may be recommended, if echo cardiography gives evidence for pulmonary hypertension or if it is difficult to differentiate between right and left heart failure. The presence of pulmonary hypertension which is of prognostic relevance has to be considered when grading reduction in earning capacity.For interpretation of spirometry values the new GLI reference values has to be applied. Grading of impairment is due to the recommendation of the DGP.According to current medical scientific knowledge it is unclear, whether certain disorders of the rheumatic group such is scleroderma or Caplan syndrome which are sometimes associated with silicosis (or coal workers' pneumoconiosis) belong in toto to the occupational disease number 4101 (silicosis). Within this context, additional studies are needed to clarify the role of occupational quartz exposure and other risk factors.The guideline working group hopes that this update will help to optimize diagnostics and expert opinion of silicotic patients.

A study on silicosis among employees of a silica processing factory in the Central Province of Sri Lanka.

The silica industry is rapidly expanding in Sri Lanka. The main objective of this study was to assess the prevalence of silicosis among workers exposed to silica dust, and to describe the disease pattern of the affected. We also screened the affected workers for tuberculosis. Employees of a silica factory (n=250) were screened using a questionnaire. Details of duration of silica exposure and work category within the industry were recorded. All symptomatic workers were investigated with chest radiography and screened for tuberculosis. International Labour Organisation criteria for diagnosis of silicosis were used for diagnosis. Of the 250 employees 25 (10%) had respiratory symptoms. Chest radiographs of 14 workers (5.6%) showed abnormalities diagnostic of silicosis. The mean age of the affected workers was 29 years. One worker had radiological changes suggestive of progressive massive fibrosis. Of 14 patients, 13 had duration of exposure less than 10 years suggestive of accelerated silicosis. Among the 14 workers diagnosed with silicosis five (35.7%) had Mantoux induration of more than 10 mm suggestive of latent tuberculesis. Silica workers at the investigated industrial facility are at a significant risk of developing accelerated silicosis. Prevalence of infection with mycobacteria was high. Education of workers, improvement of protective measures and regular monitoring of the work environment should be undertaken to avert this deadly disease.

Radiological Evaluation of Artificial Stone Silicosis Outbreak: Emphasizing Findings in Lung Transplant Recipients.

The aim of this study was to describe the computed tomography (CT) findings and correlate pulmonary function tests (PFTs) of silicosis patients with emphasis on the findings in lung transplantation (LTX) recipients. We studied the chest CT scans from 82 marble workers exposed to artificial stone dust and who had a diagnosis of silicosis, of whom 13 patients underwent LTX. Silicosis-associated findings were graded and correlated to concomitant PFT. A statistically significant inverse relationship was found between chest CT scores and PFT including forced expired volume in the first second (r = -0.54, P < 0.0001), total lung capacity (r = -0.4, P < 0.0001), and diffusion capacity for carbon monoxide single breath % (r = -0.6, P < 0.0001) parameters. Progressive massive fibrosis indicating advanced and complicated silicosis was found in 85% of LTX patients, as compared with 40% in patients with maintained pulmonary function. Ground-glass opacities were seen in some LTX patients with or without signs of progressive massive fibrosis. Two of these patients had silicoproteinosis diagnosed within the resected lung, indicating an acute or accelerated form of silicosis. This silicosis current outbreak is important because of the worldwide use of this and similar high-silica-content, artificial stone products, which can cause progressive severe forms of silicosis. Along with standard clinical assessment and PFT, CT parameters are indicative measures of the disease severity.

Silicosis and renal disease: insights from a case of IgA nephropathy

A 68-yr-old male, smoker, is admitted for proteinuria (2,800 mg/24 h) and reduced renal function (serum creatinine 2 mg/dl, GFR 35 ml/min). Renter, he started working 20-yr-old as a sandstone cave miner. Despite the high levels of silica dusts, he reported no mandatory use of airways protection devices during the first 25 yr of activity. No clinical or radiological signs of silicosis or pneumoconiosis where reported until the year of retirement (1997). Erythrocyte sedimentation rate (91 mm/h) and C reactive protein (35 mg/l) suggested a pro-inflammatory status. High serum IgA was found (465 mg/dl). A renal biopsy identified glomerular sclerosis with IgA deposition, signs of diffuse vasculitis and tubular atrophia suggesting a diagnosis of IgA nephropathy. Chest X-Rays showed emphysema and diffuse nodularity suggesting diagnosis of silicosis. Chest tomography was also positive for mild signs of silicosis with silicotic nodules and without honeycombing. IgA nephropathy is the most common type of glomerulonephritis worldwide. Several clues suggest a genetic or acquired abnormality of immune system as a trigger of the increased production of IgA. In our case report, simultaneous kidney and pulmonary disease could suggest same triggers (e.g. exposure to virus, bacteria or environmental agents) inducing IgA synthesis and pulmonary immune system activation.

Bilateral spontaneous pneumothorax in chronic silicosis: a case report.

Silicosis is an occupational lung disease caused by inhalation of crystalline silica. People working in occupations like sandblasting, surface drilling, tunneling, silica flour milling, ceramic making, and so forth are predisposed to develop silicosis. Crystalline forms of silica are more fibrogenic than the amorphous forms, highlighting the importance of the physical form in pathogenesis. Lung biopsy is rarely performed for the diagnosis of silicosis as it can easily be detected by occupational history and radiological features. Patients with silicosis can develop complications like tuberculosis, lung cancer, progressive massive fibrosis, cor pulmonale, broncholithiasis, or tracheobronchial compression by lymph nodes. Pleural involvement in silicosis is rare. Spontaneous pneumothorax is a pleural complication that can develop in such patients. Usually in silicosis pneumothorax is unilateral. We hereby report the lung biopsy findings and discuss the mechanism of pneumothorax development in a case of chronic silicosis who, later on died during the course of the disease.