Document 44dGRrN4y5mopw2KdOG6zLxpp

FILE NAME: Abex (ABX) DATE: 1946 A p r il DOC#: ABX023 DOCUMENT DESCRIPTION: Conference Presentation by LE Hamlin, Medical Director of American Brake Shoe Company - Chest Conditions Simulating Silicosis O' . . . : O Chest Conditions Sim ulating Silicosis L E. HAMLIN, M.D., F..C.S., . Medical Director, American Brake Shoe Company, Chicago PLAINTIFF'S EXHIBIT A B-77 IN RECENT years the recognition of true occupational fibrosis has become more difficult because of an ever increasing number of conditions which produce patterns in the roentgenogram resembling silicosis. These are by no means confined to diseases caused by the inhalation of dust but range all the way from cer tain heart afflictions to the exaggerated linear mark ings representing vascular changes in the lungs associated with advancing age. Their careful ap praisal as a health consideration as well as an indus trial complication therefore becomes more essential as new complexities appear. The following classification of diseases whose x-ray pattern may be confused with that of silicosis is offered not as a complete listing but as one which includes those derived from a search of the available literature. Mycotic infections have been placed in the non-indus trial group because the majority of them occur without any relationship to specific occupations. However, they do result, in some instances, from occupational ex posure. Chest Conditions W hose X-rays Sim ulate Silicosis A. Industrial I. Organic II. Inorganic (Inert) (Toxic) (Proliferative) B. Non-Industrial I. Mycotic (Yeasts and Molds) II. Miscellaneous (a) Byssinosis (b) Bagassosis ' (c) Tabacosis (a) Anthracosis (b) Radiopaque Deposits-- Barium (Baritosis) . Iron (Siderosis) Tin , (c) Beryllium : (d) Asbestosis ' (a) Aspergillosis (b) Moniliasis ' (c) Wood dust spores . (d) Coccidioidomycosis (e) Blastomycosis (f) Actinomycosis (a) Miliary tuberculosis (b) Sarcoidosis (c) Mitral Stenosis - (d) Cancer (Mtastass) (e) Vascular changes (f) Miliary calcicosis (Wheatena) (g) Polycythaemia Vera Since the year 1818 certain pulmonary conditions are believed to have developed as a result of exposure to dust in the cotton industry. Reports from Europe as well as from this country indicate that prolonged ex posure to high concentrations of cotton dust have caused definite symptoms and permanent 'disability. In England the Byssinosis Act of 1940 awardscompen sation for total disability following periods of exposure in cotton mills up to 20 years. In the United States the existence of byssinosis as an occupational disease -------- ti. Presented at the Annual Meeting: of the A merican Association Industrial P hysicians and Surgeons a t Chicago, A pril 11, 1$46. is questionable. A few cases have been reported from Eastern textile mills but after a vqry thorough inves tigation of the cotton industry in Mississippi in 1944, Ritter and Nussbaum were unable to demonstrate any x-ray findings characteristic of the disease, either in employees in the cotton mills or in the files of private roentgenologists or the State Tuberculosis Sanatorium. They did find certian allergic individuals who showed very definite asthmatic reaction to high.concentrations of cotton dust, but otherwise, clinical evidence was lacking. Postmortem and histological examinations re vealed nothing of a specific nature. They concluded that "no evidence was found to clarify or even support the existence of byssinosis as a clinical entity arising among employees exposed to Upland cotton in a cross section of that industry in Mississippi." Bagassosis is the name given to an industrial disease observed in a few workers in the sugar-cane industry. The disease is described by Castleden and Hamilton Patterson and also Gillison and Taylor in the British Medical Journal in 1942. They state that "bagasse," a waste product after the sugar has been extracted, Is used in the manufacture of board. The material is crushed or shredded into small fragments, the fibres of which contain about 1% protein and 5 to 7% silica. Symptoms after one to two months' exposure, con sisted of dyspnoea, cyanosis, violent cough, scanty sputum, occasionally blood streaked, and mild eleva tion'of temperature. The .x-ray suggested a bilateral pneumonia of the influenzal type which either resolved completely after several weeks or left the patient with some degree of residual fibrosis. As in the case of byssinosis an allergic response in the lungs to this dust was a definite possibility. . , ' , Tabacosis has been described as far back as 1865 as producing disease in the lungs. However, very few cases seem to have been reported. In Argentina and Brazil the condition is considered an occupational dis ease and is compensable. C. F. Long, after a period of 10 years experience among 4,000 workers in the tobacco industry, made a special investigation, of over 1,247 who had been subjected to tobacco dust and compared them to 1,007 who had never been exposed. He con cluded that "Tabacosis does not develop in the lungs of those who inhale tobacco dust." ' Some inorganic dusts produce alterations in the lungs which are represented by a mild accentuation of the linear markings in the x-ray. Included in this group are dusts from such materials as limestone, marble, talc, chalk, calcined magnesium for insulation, furnace linings, carbon and cement Since they are re'atively inert and non-productive of symptoms, their presence is only detectable by x-ray and the shadows observed may resemble the exaggerated lineal pattern of pre-silicotic stages. Dusts from substances like barium, iron and tin, can result in radiopaque deposits in the perivascular lymphatics and interalveolar septa which cast shadows in the roentgenogram closely simulating those of dis crete, nodular silicosis. The deposits have real sig- SPN Y 000235 nificance from the standpoint ' litigation but are of publicity it has L 'ived would indicate. A hydrated no apparent consequence as far as health or disability magnesium silicate, it is believed to produce its effects is concerned. In 1938 Sander and Bnzer described through mechanical plugging of the alveoli by long findings in welders who had no known exposure to fibres (over two microns) which have an irritating silica but whose chest x-rays showed marked nodula effect on the lung tissue. There is some associated tions almost indistinguishable from silicosis which fibrosis which is responsible for the characteristic were demonstrated to be the result of inhalation of ground glass appearance observed in the roentgeno iron oxide fumes. The borders of these shadows were gram. The greatest occupational hazard exists in min generally more sharply defined than those of silicotic ing, handling and crushing crude asbestos. nodules and the hilium shadows less prominent. Post Fungi are filamentous plants of simple structure mortem findings on one case, who died from accident, which include a variety of yeasts and molds capable of gave no indication of fibrosis either grossly or his producing disease in the lungs as well as in other tologically. On microscopical section, deposits observed about the blood vessels were simple pigmentations which gave the typical Prussian Blue reaction for iron. Development of clinical symptoms and suscepti structures of the body. A common fungus, aspergillus, consists of many species of molds one of which, asper gillus fumigatus, attacks the lungs and is responsible for the disease known as aspergillosis. Monilia albicans, bility to complicating infection were lacking. In recent years our own experience with foundry grinders and burners seems to indicate that much of the nodulation observed in films of men working at a yeast-like fungus, may produce primary lesions in the lung or sometimes gain access as a secondary in vader. Infection with any type of this mold produces "Moniliasis," a disease which may affect the skin as these occupations does not represent actual silicosis well as the pulmonary structures. Coccidioidomycosis, but is the result of excessive exposure to iron oxide, Sporotrichosis and Blastomycosis are due to yeast-like similar to that described by Sander. Clinical findings organisms which generally cause a progressive infec and occupational exposure are not consistent with the tion affecting the mucous, cutaneous, subcutaneous, present conception of silicosis. The analysis o f'repre osseous and visceral structures. Involvement of the sentative samples of air borne dust by x-ray diffrac lungs does occur in some cases directly through inhala tion, petrographic and chemical examination (over a tion of spores, and sometimes fungi may be superim three year period) indicates that there is not enough posed on existing diseased area. free silica in the atmosphere to constitute a definite In 1931 Towey, Sweany and Huron described a pre hazard but enough iron oxide in finely divided form viously unrecognized disease which occurred in 38 does exist to produce the pattern noted In the x-ray. workers who came in close contact with dust from . Experimental work is now being carried on in an effort | ,maple logs. The logs had been cut for more than a year to determine the effects of this particular dust on and were not disturbed throughout a hot, moist sum- laboratory animals. mer, a circumstance favoring fungus growth. The A comparatively new disease entity caused by beryl dust, which was of the consistency of lamp black, ac lium and its compounds has recently been established. cumulated beneath the cork layer of the bark and was Beryllium is a strategic metal which was of consider liberated during peeling or sawing operations. On ex able importance during the war in the production of amination it was found to be pure spores of a fungus precision instruments. The exact effect of this metal on tentatively classified as nummularia or coniosporium the tissues of the body has not been determined but corticola. its action is thought to be a toxic one, producing der Symptoms produced by inhalation of the spores were matitis, nasal irritation, skin ulcer and chemical pneu aeute and asthmatic in character. They included dysp monitis. Van Ordstrand and his associates have re nea, cough, loss of weight and expectoration. The con ported their observations and findings in 170 cases of dition was considered an allergic response to sensitiza poisoning among workers in the beryllium industry. tion by the fungus combined with a possible toxic ele They noted that the disease was not limited to men ment in the spores. in one type of work or in one phase of production and the incidence and severity were proportional to the degree of exposure and chemical irritation of dusts and fumes. The chemical pneumonitis which developed in 38 workers represented the severest form of the disease and progressed without exacerbation or remis sion, either to complete recovery or to death. Roent genologic changes in the lung fields did not appear until two to three weeks after the onset of symptoms and physical signs. Changes were bilateral and diffuse in all cases and varied with the severity of the disease. In order of appearance the changes were (1) diffuse haziness of both lungs, (2) development of soft irregu lar areas of infiltration with prominence of peribron chial markings, (8) absorption of soft infiltration and appearance of discrete large or small conglomerate nodules scattered throughout both lung fields and (4) clearing of the lung fields after one to four months. Necropsies on five patients showed a typical pneu monitis. Fibroblasts with evidence of organization were present although in patients who recovered, no fibrosis was evident on roentgenologic examination of the chest. The so-called fibrosis due to asbestos fibres in the lungs has long been recognized p ' i occupations! .! ... ease. It does not seem to oc<" irequei-' X-ray findings were proportionate to the degree of dyspnea observed and consisted of definite mottling throughout the lower halves of the lungs with in creased hilar, basal and trunk shadows. Peribronchial markings were increased throughout both lungs, ex cept in the apices. Physical improvement with clearing of the x-ray occurred in all cases within two to three months after removal from exposure. The general characteristics of mycotic infections of the lungs are sufficiently alike to warrant their con sideration as a group. The x-ray findings may show some variation, as they do in silicosis, but usually they range from accentuated linear markings to miilarysized densities which may coalesce. Advanced cases may show discrete nodules scattered throughout the parenchyma of the lungs. The differentiation from silicosis, tuberculosis, metastatic cancer, sarcoidosis, etc., can be difficult and diagnosis in individual cases should be based on correlation of clinical evidence and exposure with the roentgenogram. Diseases such as coccidioidomycosis are endemic in some localities and while no*region is exempt, a higher incidence occurs In certain areas. There does not ap pear* to be any occupational prevalence, but cases of m- cotic infection do occur in certain industries. Re- ntly a case of primary bronchopulmonary aspergil- SPNY 000236