[Misdiagnosis of pneumoconiosis or silicotuberculosis in China: a pooled analysis of 1178 cases].

OBJECTIVE: To investigate the situation and causes of misdiagnosis of pneumoconiosis or silicotuberculosis in China by pooled analysis, and to provide a reference for the clinical diagnosis of pneumoconiosis in China and reduce the misdiagnosis rate. METHODS: A computer search was performed to collect the studies on the misdiagnosis of pneumoconiosis or silicotuberculosis published in China from 1985 to 2013. The obtained data were subjected to pooled analysis to investigate the causes of misdiagnosis and seek the measures for reducing misdiagnosis. RESULTS: Fifty-nine studies involving 1178 cases of misdiagnosed pneumoconiosis or silicotuberculosis were collected. There were 13 causes of misdiagnosis, and the most common one was the poor ability of identification due to inadequate experience in reading chest X-ray films (45.93%), followed by neglect of patient's occupational history (44.99%). Other causes of misdiagnosis included complex X-ray findings that are difficult to judge (29.03%), poor quality of chest radiographs (23.09%), and lack of regular health supervision (19.95%). CONCLUSION: Inadequate experience of physicians is the main cause of misdiagnosis of pneumoconiosis or silicotuberculosis. To reduce misdiagnosis of the disease, measures should be taken to enhance the training and evaluation of knowledge and skills of diagnosis and differential diagnosis of pneumoconiosis among physicians.

[Silicoproteinosis: a specific clinical and radiological entity]. / La silicoprotéinose : une entité radioclinique à part.

INTRODUCTION: Silicoproteinosis is a rare disease, which can cause the rapid onset of respiratory failure following massive exposure to silica dust. CASE REPORT: A 25-year-old patient presented with altered state and dyspnea. The diagnosis of military pulmonary tuberculosis was first considered and antituberculous treatment was started. The diagnosis was reconsidered due to a lack of improvement and the discovery of an 18-month history of exposure to silica. The patient had stopped work 6 months prior to hospitalization. High-resolution CT showed air space condensation associated to centrilobular nodules throughout the lungs and multiple mediastinal lymph nodes, suggesting sarcoidosis. Bronchoalveolar lavage (BAL) suggested the diagnosis of lipoproteinosis. Because of discordance between the bacteriological, radiological and the BAL results, a surgical lung biopsy was performed which led to the diagnoses of a secondary lipoproteinosis. The diagnosis of silicoproteinosis was then considered. Over a one-year follow up, the patient's respiratory failure has progressed markedly despite treatment with corticosteroids. CONCLUSION: Silicoproteinosis is a distinct pathological entity, the diagnosis of which depends on clinical and radiological features as well as BAL findings, which may avoid the need for more invasive investigations.

Silicotuberculosis and silicosis as occupational diseases: report of two cases.

INTRODUCTION: Silicosis, the most prevalent of the pneumoconioses, is caused by inhalation of crystalline silica particles. Silica-exposed workers are at increased risk for tuberculosis and other mycobacterium-related diseases. The risk of a patient with silicosis developing tuberculosis is higher (2.8 to 39 fold higher, depending on the severity of silicosis) than that found in healthy controls. OUTLINE OF CASES: The first patient was a 52-year-old male who was admitted in 2002 for the second time with dyspnoea, wheezing and fatigue over the last 11 years. He had worked in an iron smelting factory and was exposed to silica dust for 20 years. First hospitalization chest radiography showed bilateral pleural adhesions, diffuse lung fibrosis with signs of a specific lung process. Second hospitalization chest radiography showed bilateral massive irregular, non-homogenous calcified changes in the upper and middle parts of lungs. The patient died due to respiratory failure and chronic pulmonary heart in 2007. The main causes of his death were silicotuberculosis and chronic obstructive pulmonary disease. The second patient was a 50-year-old male who was admitted in 2005 for the second time with chest tightness, dyspnoea, wheezing and fatigue over the last 10 years. He had worked in an iron smelting factory and was exposed to silica dust for 30 years. First hospitalization chest radiography showed diffuse lung fibrosis and small nodular opacities. The patient was diagnosed with silicosis, small opacities sized level p/q, and profusion level 2/3. Second hospitalization chest radiography and CT showed diffuse lung fibrosis and small nodular opacities predominantly in the upper lobes. The patient was recognized as having an occupational disease, and received early retirement due to disability. CONCLUSION: In low-income countries, new cases of silicosis and associated lung cancer, chronic obstructive pulmonary disease and tuberculosis are likely to be seen for decades because necessary reduction of silica use will take time to be achieved.

[Erasmus' syndrome with pseudo-tumour masses]. / Un syndrome d'Erasmus avec des masses pseudo-tumorales.

INTRODUCTION: Erasmus' syndrome involves the association of systemic scleroderma (SS) and exposure to silica. Silicosis may precede the SS but the latter may be the presentation, in which case a history of exposure to silica should be sought as part of the diagnosis. CASE REPORT: A 46-year-old man with history of pulmonary tuberculosis presented with dyspnoea and dysphagea. Clinical examination revealed thickening of the facial skin with a pointed nose, erythema and telangiectasia, Raynaud's syndrome and sclerodactyly. A thoracic CT scan revealed bilateral, fibrotic, pseudo-tumoural masses. Antinuclear antibodies, anti-topoisomerase 1 and antihistone were positive. CONCLUSION: The clinical presentation of Erasmus' syndrome associating systemic scleroderma and pulmonary pseudo-tumours may pose a problem of differential diagnosis from lung cancer. This condition requires regular clinical and radiological monitoring, particularly as both scleroderma and silicosis increase the risk of lung cancer.

[Prospective analysis of clinical course and outcomes in silicosis patients].

The authors revealed features of clinical course and outcomes in patients with silicosis and silicotuberculosis, who worked on iron industry enterprise. The article covers comparative analysis of survival rate and mortality among silicosis patients over 14 years of observation.

Tuberculosis and silicosis: epidemiology, diagnosis and chemoprophylaxis.

Silicosis, the most prevalent of the pneumoconioses, is caused by inhalation of crystalline silica particles. Silica-exposed workers, with or without silicosis, are at increased risk for tuberculosis and nontuberculous mycobacteria-related diseases. The risk of a patient with silicosis developing tuberculosis is higher (2.8 to 39 times higher, depending on the severity of the silicosis) than that found for healthy controls. Various regimens for tuberculosis chemoprophylaxis in patients with silicosis have been studied, all of which present similar efficacy and overall risk reduction to about one half of that obtained with placebo. Long-term regimens have potential side effects (particularly hepatotoxicity). In addition, the use of such regimens can jeopardize adherence to treatment. The current guidelines recommend that tuberculin skin tests be performed, and, if positive, that chemoprophylaxis be instituted. There are several possible regimens, varying in terms of the drugs prescribed, as well as in terms of treatment duration. We recommend the use of isoniazid at 300 mg/day (or 10 mg/kg/day) for six months for patients with silicosis, as well as for healthy patients with periods of exposure to silica longer than 10 years and strongly positive tuberculin skin test results (induration > or = 10 mm). Nevertheless, further studies are necessary so that indications, drugs, doses and duration of chemoprophylaxis regimens can be more properly defined.

Tuberculose e silicose: epidemiologia, diagnóstico e quimioprofilaxia / Tuberculosis and silicosis: epidemiology, diagnosis and chemoprophylaxis

A silicose, a mais prevalente das pneumoconioses, é provocada pela inalação de partículas de sílica cristalina. Indivíduos expostos à sílica, com ou sem silicose, apresentam risco aumentado de tuberculose e de micobacterioses não-tuberculosas. O risco de silicóticos desenvolverem tuberculose em relação a controles sadios varia de 2,8 a 39 vezes, em conformidade com a gravidade da doença de base. Têm sido estudados diferentes esquemas de quimioprofilaxia para tuberculose em silicóticos, todos com eficácia semelhante e com redução final de risco para cerca da metade em relação ao uso de placebo. São, no entanto, esquemas de longa duração, o que, acrescido dos possíveis efeitos colaterais (particularmente hepatotoxicidade), podem prejudicar a aderência. As diretrizes atuais recomendam a realização de prova tuberculínica e, se positiva, a instituição de quimioprofilaxia. São vários os esquemas possíveis, tanto em termos de drogas quanto de duração. Nossa recomendação é de que se use isoniazida na dose de 300 mg/dia (ou 10 mg/kg/dia) por seis meses para os indivíduos com silicose ou sadios com exposição superior a 10 anos, se forem reatores fortes à prova tuberculínica (induração > 10 mm). São necessários, no entanto, novos estudos para que indicações, drogas, doses e duração da profilaxia sejam definidas mais apropriadamente.

Silicosis, the most prevalent of the pneumoconioses, is caused by inhalation of crystalline silica particles. Silica-exposed workers, with or without silicosis, are at increased risk for tuberculosis and nontuberculous mycobacteria-related diseases. The risk of a patient with silicosis developing tuberculosis is higher (2.8 to 39 times higher, depending on the severity of the silicosis) than that found for healthy controls. Various regimens for tuberculosis chemoprophylaxis in patients with silicosis have been studied, all of which present similar efficacy and overall risk reduction to about one half of that obtained with placebo. Long-term regimens have potential side effects (particularly hepatotoxicity). In addition, the use of such regimens can jeopardize adherence to treatment. The current guidelines recommend that tuberculin skin tests be performed, and, if positive, that chemoprophylaxis be instituted. There are several possible regimens, varying in terms of the drugs prescribed, as well as in terms of treatment duration. We recommend the use of isoniazid at 300 mg/day (or 10 mg/kg/day) for six months for patients with silicosis, as well as for healthy patients with periods of exposure to silica longer than 10 years and strongly positive tuberculin skin test results (induration > 10 mm). Nevertheless, further studies are necessary so that indications, drugs, doses and duration of chemoprophylaxis regimens can be more properly defined.

[A case of silicotuberculosis with difficulty in its diagnosis].

A 68-year-old man who had worked as a stone mason for more than 50 years with a heavy smoking history consulted our clinic with symptoms of cough, low grade fever, weightloss, malaise and a single expectoration of hemo-sputum. He had been diagnosed as silicosis by the mass survey 5 years ago based on nodular shadows with egg-shell calcification in hilar lymphnodes on his chest radiography, and has received chest radiographic examination once a year. As the author was not so familiar with the radiographic features of silicotuberculosis, it was difficult to interprete ill-defined contour of silicotic nodules accompanied by patchy opacities formation in right midlung field and silicotic conglomeration accompanied by an ischemic cavity in the left basal segments. A definitive diagnosis could not be established until 10 months later when a second attack of exacerbation of silicotuberculosis occurred showing multiple thin walled fresh tuberculous cavities on the chest radiography with positive smear and culture. Among multiple tuberculous cavities, there was a cirrhotic-walled cavity caused by endogenous reactivation of a quiescent tuberculous lesion on the right apex. This lesion was considered to be the source of dissemination of this case. Finally, it took about two and a half years before establishing the diagnosis in this case because of a series of doctors delays. He was treated successfully with antituberculous drugs for one and a half years including one year rifampicin medication. The clinico-pathological findings of silicotic conglomeration in the left basal segments were discussed based on the findings of transbronchial biopsy from occluded B10 and chest radiographic findings, and it was revealed that silicotic conglomeration might consist of inflammatory granulation combined with granulomatous tubercle, but not a fibrous lesion.

[Bronchoalveolar lavage in the diagnosis of occupational pulmonary diseases in miners]. / Bronkhoal'veoliarnyi lavazh v diahnostytsi profesiinykh lehenevykh zakhvoriuvan' u hirnykiv.

One of objective methods of early and differential diagnosis of occupational pulmonary diseases in miners (pneumoconiosis, silicotuberculosis, dust bronchitis) is bronchoscopy with a cytologic examination of bronchoalveolar lavage fluid (BAF). BAF-examination was carried out in a total of 88 patients with incipient and advanced forms of dust bronchitis, pneumoconiosis and silicotuberculosis. A direct relationship has been revealed between a decline in local cell-bound immunity caused by a dust-inducted affection mononuclear phagocytes and advancing of stages of dust-related diseases.

[Significance of immunoenzyme analysis in early diagnosis of dust bronchitis]. / Znachennia imunofermentnoho analizu dlia rann'oï diahnostyky pylovoho bronkhitu.

Measurement of levels of antibodies to a causative agent of tuberculosis with the aid of the enzyme immunoassay can serve as one of methods for early diagnosis of infectious- and dust diseases. Patients with clinically established diagnosis of dust bronchitis, latent silicotuberculosis and manifest silicotuberculosis demonstrated a significantly higher level of antituberculous antibodies in blood plasma as compared to controls. Establishment of the above fact permits regarding a major proportion of dust bronchitis as a silicotuberculous process.

Perfil de 300 trabalhadores expostos à sílica atendidos ambulatorialmente em Belo Horizonte / Profile of 300 workers exposed to silica seen in an university outpatient clinic

Introdução: A silicose é a pneumoconiose de maior prevalência no Brasil, sendo a maioria dos casos proveniente do Estado de Minas Gerais. Apesar de ser uma doença evitável, continuam ocorrendo epidemias localizadas. Objetivo: Descrever o perfil dos trabalhadores atendidos no Ambulatório de Doenças Profissionais do Hospital das Clínicas da Universidade Federal de Minas Gerais. Material e métodos: Foram estudados 300 prontuários de trabalhadores expostos à sílica em diversas atividades profissionais, atendidos no período de 1989 a 2000, sendo analisados dados clínico-ocupacionais, espirométricos e radiológicos. Realizaram-se análises univariadas, utilizando o teste do qui-quadrado e teste t. Resultados e conclusão: A média de idade dos pacientes expostos foi de 51 anos, com tempo médio de exposição de 15,6 anos. Diagnosticaram-se radiologicamente 126 (42 por cento) casos de silicose, constatando-se que, quanto mais avançada a categoria radiológica da doença, piores foram os resultados à espirometria e mais freqüentes as associações com tuberculose e com limitação crônica ao fluxo aéreo. O mercado de trabalho formal representou o principal vínculo empregatício, sendo a mineração a principal atividade exercida, responsável pela exposição de 197 indivíduos (66 por cento). Os trabalhadores do mercado informal foram aqueles que apresentaram achados radiológicos indicativos de formas mais avançadas da doença, sugerindo piores condições de exposição à sílica, neste grupo de trabalhadores

[Dispensary registration groups and follow-up periods of patients with silicotuberculosis]. / O gruppakh dispansernogo ucheta i srokakh nabliudeniia bol'nykh silikotuberkulezom.

Silicosis is the most common and most frequently tuberculosis-complicated pneumoconiosis with poor prognosis. So a procedure for following up patients with silicotuberculosis requires revision and elaboration. Long-term follow-ups have made it possible to define early signs of this disease and to propose a number of techniques for its early diagnosis, such as chest computed tomography and polarization serum crystal microscopy. Specific recommendations on follow-ups of patients with silicosis and silicotuberculosis by a phthisiologist are laid down.

[Aspects of silicotuberculosis course in workers of highly aluminous mullite refractories]. / Osobennosti techeniia silikotuberkuleza u rabochikh na proizvodstve vysokoglinozemistykh mullitovykh ogneupornykh izdelii.

The article covers differential diagnostic features of pulmonary tuberculosis and pneumoconiosis in workers engaged into mullite refractories production. The authors suggest that the disease courses as a new form of lung disorder--mullitosis.

Sílico-tuberculose em pacientes atendidos em centro de Referência em Tuberculose do Estado de Säo Paulo / Silico-tuberculosis in pacients treated at Centro de Referência em Tuberculose in Säo Paulo

Objetivo: Analisar aspectos diagnósticos, de tratamento e evoluçäo da tuberculose em portadores de silicose, em Centro de Referência em Tuberculose do Estado de Säo Paulo. Métodos: Estudo retrospectivo, descritivo, realizado através do levantamento e análise de prontuários médicos de uma populaçäo pré estabelecida, no período de 1982 à 1999, com 82 pacientes com silicose e, destes, 44 desenvolveram tuberculose. Foi estabelecido um grupo de controle, obedecendo os seguintes critérios de pareamento: dois controles para cada caso, mesmo período de admissäo, sexo masculino, faixa etária com intervalo de cinco anos e todos portadores de tuberculose pulmonar bacilífera. Nas análises estatísticas, utiliza testes de associaçäo (Qui-Quadrado), comparaçäo entre médias e análise de variância. Resultados: Os 44 pacientes (53,6 por cento) portadores de sílico- tuberculose eram do sexo masculino, com predomínio da raça branca (55,8 por cento), e idade média de 53,04 anos. 22 tinham baciloscopia e cultura de escarro positiva. O tempo médio de sintomas foi de 5,74 meses, significativamente maior que no grupo controle. O esquema de tratamento com Rifampicina (R), Isoniazida (H) e Pirazinamida (P) e o tempo de tratamento- média de 9 meses- foram semelhantes nos dois grupos. A negativaçäo do escarro ocorreu em média 5 meses após o início do tratamento no grupo exposto e no grupo controle, com alta cura de 80 por cento dos pacientes nos dois grupos. Comparando o número de cruzes da baciloscopia e cultura de escarro entre grupos, näo houve diferença estatísticamente significante entre eles. Conclusöes: Aspectos diagnósticos: houve diferença significativa quanto ao tempo de sintomas entre grupos exposto e controle, mostrando que os portadores de sílico-tuberculose tiveram doença mais prolongada. 50 por cento dos expostos apresentaram baciloscopia positiva no exame de escarro e o tempo de negativaçäo do escarro, foi semelhante nos dois grupos. 69 por cento dos expostos tinham à radiografia de tórax, categoria maior ou igual a 2. Aspectos do tratamento: O tempo de tratamento foi também semelhante nos grupos, com uma média de duraçäo de 9 meses. Quanto ao tipo de alta, 84 por cento dos expostos tiveram alta cura, assim como no grupo controle, mostrando uma eficácia na quimioterapia instituída.

[Immunological changes in dust-induced lung diseases]. / Immunologicheskie izmeneniia pri pylevoi patologii legkikh.

One hundred and forty five patients with different forms of dust-induced lung disease and 57 controls having no contacts with industrial aerosols were examined. It was ascertained that clinical and functional evidence cannot predict the course of the disease and the development of infectious complications (silicotuberculosis, mechanic bronchitis). Impaired humoral immunity and nonspecific resistance in dust-induced lung disease depend on the type of disease and predispose to infectious complications. Predisposition to occupational lung diseases (pneumoconioses, mechanical bronchitis) is associated with increases in the concentrations of plasma fibronectin and serum IgA and a decrease in serum mucin antigen levels. In chronic mechanical bronchitis, there were lower activities of lysozyme and complement and elevated serum IgM and IgG concentrations. Fibronectin, total IgE and the inflammatory marker the mucin antigen 3EG5 are involved in immunological inflammation in dust-induced lung disease. It is worth of determining the factors of humoral immunity and nonspecific resistance in workers contacting with high concentrations of industrial aerosols and in patients with dust-induced diseases to make a precise assessment of the time course of changes in a pathological process and to define a risk for infectious complications.