Asbestosis

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Asbestosis is the long-term inflammation and scarring of the lungs due to asbestos. Symptoms may include shortness of breath, coughing, wheezing, and chest pain. Complications may include lung cancer, mesothelioma, and pulmonary heart disease.

Asbestosis is caused by breathing in asbestos fibers. Generally requires a relatively large exposure over a long period of time. Such exposure levels usually only occur in those who work with the material. All types of asbestos fibers are associated with concerns. It is generally recommended that existing asbestos be left undisturbed. The diagnosis is based on a history of exposure along with medical imaging. Asbestosis is a type of interstitial lung fibrosis.

No special treatment. Recommendations may include influenza vaccination, pneumococcal vaccination, oxygen therapy, and smoking cessation. Asbestosis affects about 157,000 people and result in 3,600 deaths by 2015. The use of asbestos has been banned in a number of countries in an effort to prevent disease.

Video Asbestosis

Signs and symptoms

Signs and symptoms of asbestosis usually manifest after a large amount of time elapsed after exposure to asbestos, often decades under current conditions in the US. The main symptom of asbestosis is generally a slow onset of breathlessness, especially with physical activity. Clinically sophisticated asbestos cases can cause respiratory failure. When a doctor listens with a stethoscope to a person's lung with asbestosis, they may hear inspiring voices.

A typical pulmonary function finding in asbestosis is a restrictive ventilation defect. It manifests as a reduction in lung volume, especially vital capacity (VC) and total lung capacity (TLC). TLC can be reduced by alveolar wall thickening; However, this is not always the case. Large airway functions, as reflected by FEV ₁ /FVC, are generally well preserved. In severe cases, pulmonary function decline due to lung stiffness and decreased TLC can induce heart failure (cor pulmonale). In addition to restrictive defects, asbestosis can result in decreased diffusion capacity and low oxygen levels in arterial blood.

Maps Asbestosis

Cause

The cause of asbestosis is the inhaling of microscopic asbestos mineral fibers suspended in the air. In the 1930s, E. R. A. Merewether found that greater exposure led to greater risk.

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Pathogenesis

Asbestosis is a scarring of lung tissue (beginning around the bronchioles terminal and alveolar channel and extending into the alveolar wall) resulting from inhaling asbestos fibers. There are two types of fiber: amphibole (thin and straight) and serpentine (curly). All forms of asbestos fibers are responsible for human disease because they are able to penetrate into the lungs. When the fiber reaches the alveoli (the air sacs) in the lungs, where oxygen is transferred into the blood, foreign bodies (asbestos fibers) lead to activation of the local immune system of the lung and trigger an inflammatory reaction dominated by pulmonary macrophages that respond to chemotactic factors activated by fiber. This inflammatory reaction can be described as chronic rather than acute, with the development of a slow immune system trying to eliminate foreign fibers. Macrophage phagocytosis (ingest) fibers and stimulates fibroblasts to store connective tissue. Because of the natural resistance of asbestos fibers to digestion, some macrophages are killed and others release chemical signals of inflammation, attract further lung macrophages and fibrolastic cells that synthesize fibrous scar tissue, which eventually become spread and can progress in heavily exposed individuals. These tissues can be viewed microscopically soon after exposure to animal models. Some of the asbestos fibers become plated by an iron-containing protein material (ferruginous body) in case of heavy exposure where about 10% of the fibers become coated. Most inhaled asbestos fibers remain uncoated. Approximately 20% of inhaled fibers are transported by the cytoskeletal component of the alveolar epithelium to the lung interstitial compartment in which they interact with macrophages and mesenchymal cells. Cytokines, altering the growth factor of beta and tumor necrosis factor alpha, seem to play a major role in the development of scar tissue because this process can be blocked on animal models by preventing expression of growth factors. The result is fibrosis in the interstitial space, resulting in asbestosis. This fibrotic scar causes the thickened alveolar wall, which reduces the elasticity and diffusion of the gas, reduces the transfer of oxygen to the blood and the removal of carbon dioxide. This can cause shortness of breath, a common symptom shown by individuals with asbestosis.

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Diagnosis

According to the American Thoracic Society (ATS), the general diagnostic criteria for asbestosis are:

• The evidence of structural pathology is consistent with asbestosis, as documented by imaging or histology
• The evidence of cause by asbestos as documented by occupational and environmental history, exposure markers (usually pleural plaques), asbestos body recovery, or other means
• Exception reasons make sense for findings

Abnormal chest X-rays and their interpretations remain the most important factor in determining the presence of pulmonary fibrosis. The findings usually appear as small irregular parenchymal disorders, especially in the lung bases. Using the ILO Classification system, "s", "t", and/or "u" opacities predominate. High resolution CT or CT (HRCT) is more sensitive than plain radiographs when detecting pulmonary fibrosis (as well as changes in the underlying pleura). More than 50% of people affected by asbestosis develop plaque in the parietal pleura, the space between the chest wall and the lungs. Once clear, radiographic findings in asbestosis can slowly develop or remain static, even in the absence of further exposure to asbestos. Rapid developments indicate an alternative diagnosis.

Asbestosis resembles many widespread interstitial lung disease, including other pneumoconiosis. The differential diagnosis includes idiopathic pulmonary fibrosis (IPF), hypersensitivity pneumonitis, sarcoidosis, and others. The presence of pleural plaques may provide evidence supporting the cause by asbestos. Although lung biopsy is usually unnecessary, the presence of the asbestos body in association with pulmonary fibrosis forms a diagnosis. In contrast, interstitial pulmonary fibrosis in the absence of the asbestos body is most likely not asbestosis. The body of asbestos in the absence of fibrosis shows exposure, not disease.

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Treatment

There is no cure available for asbestosis. Oxygen therapy at home is often necessary to reduce shortness of breath and improve the underlying low blood oxygen level. Treatments that support the symptoms include respiratory physiotherapy to secrete secretions from the lungs with postural drainage, chest percussion, and vibration. Drugs Nebulisation may be prescribed to loosen secretions or cure the underlying chronic obstructive pulmonary disease. Immunization against pneumococcal pneumonia and annual influenza vaccination is given due to increased sensitivity to disease. Those with asbestosis are at higher risk for certain cancers. If the person smokes, stopping the habit reduces further damage. Periodic pulmonary function tests, chest x-ray, and clinical evaluation, including cancer screening/evaluation, are provided to detect additional hazards.

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Society and culture

Legal issues

The death of British textile worker Nellie Kershaw in 1924 of pulmonary asbestosis was the first case described in the medical literature, and the first published report on diseases associated with asbestos exposure in the workplace. However, his former employer (Turner Brothers Asbestos) denied that asbestosis even existed because the medical condition was not officially recognized at the time. As a result, they are not responsible for his injuries and pay no compensation, either to Kershaw during his last illness or to the family he left behind after his death. Even so, the findings of his death checks are very influential as far as they lead parliamentary inquiry by the British Parliament. The investigation officially acknowledged the existence of asbestosis, recognizing that it was harmful to health and concluded that it was irrefutably linked to inhaling prolonged asbestos dust. After establishing the medical and judicial asbestosis presence, the report produced the first Asbestos Industrial Act published in 1931, which came into effect on 1 March 1932.

The first lawsuit against asbestos producers took place in 1929. Since then, many lawsuits have been filed against asbestos manufacturers and entrepreneurs, for neglecting to implement security measures after the relationship between asbestos, asbestosis and mesothelioma is known (some reports seem to put this as early as 1898 in modern times). Liabilities resulting from the number of lawsuits and people affected have reached billions of dollars. The number and method of allocating compensation has been the source of many court cases, and the government's efforts to resolve existing and future cases.

To date, about 100 companies have declared bankruptcy at least in part due to asbestos related obligations. In accordance with Chapter 11 and Ã, § 524 (g) of the federal bankruptcy code, the company may transfer certain liabilities and assets to the confidence of personal asbestos injury, which is then responsible for compensating current and future claimants. Since 1988, 60 trusts have been set up to pay claims with total assets of approximately $ 37 billion. From 1988 to 2010, an analysis from the United States Government Accountability Office showed that trust had paid around 3.3 million claims worth about $ 17.5 billion.

Important case

Some famous people who have died from asbestos-related lung fibrosis include:

• Bernie Banton, advocate of social justice
• Nellie Kershaw, the first person to be diagnosed with asbestos-related illness, 1924
• John MacDougall, politician
• Steve McQueen, actor
• Theodore Sturgeon, author

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References

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External links

• "Asbestos Toxicity". Case Study of ATSDR in Environmental Medicine . US Department of Health and Human Services.
• "Health and safety of Asbestos". UK Health and Safety Executive.
• "Asbestos Exposure". National Cancer Institute, USA.
• "Environmental Health Guidance Notes - Asbestos" (PDF) . Health Queensland. May 2002.
• "Asbestos". IRIS - Integrated Risk Information System . US Environmental Protection Agency. CASRN 1332-21-4.

Source of the article : Wikipedia