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Silicosis (previously miner's phthisis, grinder's asthma, potter's rot and other occupation-related names) is a form of occupational lung disease caused by inhalation of crystalline silica dust, and is marked by inflammation and scarring in the form of nodular lesions in the upper lobes of the lungs. It is a type of pneumoconiosis.〔Derived from Gr. πνεῦμα ''pneúm''|a (lung) + buffer vowel ''-o-'' + κόνις ''kóni''|s (dust) + Eng. scient. suff. -''osis'' (like in asbest''osis'' and silic''osis'', see ref. 10).〕 Silicosis (particularly the acute form) is characterized by shortness of breath, cough, fever, and cyanosis (bluish skin). It may often be misdiagnosed as pulmonary edema (fluid in the lungs), pneumonia, or tuberculosis. Silicosis resulted in 46,000 deaths globally in 2013 down from 55,000 deaths in 1990. The name ''silicosis'' (from the Latin ''silex'', or flint) was originally used in 1870 by Achille Visconti (1836-1911), prosector in the Ospedale Maggiore of Milan.〔''United States Bureau of Mines,'' "Bulletin: Volumes 476-478", ''U.S. G.P.O., (1995),'' p 63.〕 The recognition of respiratory problems from breathing in dust dates to ancient Greeks and Romans.〔Rosen G: The History of Miners' Diseases: A Medical and Social Interpretation. New York, Schuman, 1943, pp.459-476.〕 Agricola, in the mid-16th century, wrote about lung problems from dust inhalation in miners. In 1713, Bernardino Ramazzini noted asthmatic symptoms and sand-like substances in the lungs of stone cutters. With industrialization, as opposed to hand tools, came increased production of dust. The pneumatic hammer drill was introduced in 1897 and sandblasting was introduced in about 1904, both significantly contributing to the increased prevalence of silicosis. ==Classification== Classification of silicosis is made according to the disease's severity (including radiographic pattern), onset, and rapidity of progression.〔NIOSH Hazard Review. Health Effects of Occupational Exposure to Respirable Crystalline Silica. DHHS 2002-129. pp. 23.〕 These include: * ''Chronic simple silicosis'' Usually resulting from long-term exposure (10 years or more) to relatively low concentrations of silica dust and usually appearing 10–30 years after first exposure.〔Weisman DN and Banks DE. Silicosis. In: Interstitial Lung Disease. 4th ed. London: BC Decker Inc. 2003, pp391.〕 This is the most common type of silicosis. Patients with this type of silicosis, especially early on, may not have obvious signs or symptoms of disease, but abnormalities may be detected by x-ray. Chronic cough and exertional dyspnea are common findings. Radiographically, chronic simple silicosis reveals a profusion of small (<10 mm in diameter) opacities, typically rounded, and predominating in the upper lung zones. * ''Accelerated silicosis'' Silicosis that develops 5–10 years after first exposure to higher concentrations of silica dust. Symptoms and x-ray findings are similar to chronic simple silicosis, but occur earlier and tend to progress more rapidly. Patients with accelerated silicosis are at greater risk for complicated disease, including progressive massive fibrosis (PMF). * ''Complicated silicosis'' Silicosis can become "complicated" by the development of severe scarring (progressive massive fibrosis, or also known as conglomerate silicosis), where the small nodules gradually become confluent, reaching a size of 1 cm or greater. PMF is associated with more severe symptoms and respiratory impairment than simple disease. Silicosis can also be complicated by other lung disease, such as tuberculosis, non-tuberculous mycobacterial infection, and fungal infection, certain autoimmune diseases, and lung cancer. Complicated silicosis is more common with accelerated silicosis than with the chronic variety. * ''Acute silicosis'' Silicosis that develops a few weeks to 5 years after exposure to high concentrations of respirable silica dust. This is also known as silicoproteinosis. Symptoms of acute silicosis include more rapid onset of severe disabling shortness of breath, cough, weakness, and weight loss, often leading to death. The x-ray usually reveals a diffuse alveolar filling with air bronchograms, described as a ground-glass appearance, and similar to pneumonia, pulmonary edema, alveolar hemorrhage, and alveolar cell lung cancer. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Silicosis」の詳細全文を読む スポンサード リンク
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