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DOI: 10.4046/trd.2010.68.2.67 ISSN: 1738-3536(Print)/2005-6184(Online) Tuberc Respir Dis 2010;68:67-73 CopyrightC2010. The Korean Academy of Tuberculosis and Respiratory Diseases. All rights reserved. 탄광부진폐증환자에동반된기관지탄분섬유화증의임상적의의 울산대학교의과대학강릉아산병원 1 내과학교실, 2 영상의학교실김미혜 1, 이홍열 1, 남기호 1, 임재민 1, 정복현 1, 류대식 2 Original Article The Clinical Significance of Bronchial Anthracofibrosis Associated with Coal Workers Pneumoconiosis Mi Hye Kim, M.D. 1, Hong Yeul Lee, M.D. 1, Ki Ho Nam, M.D. 1, Jae Min Lim, M.D. 1, Bock Hyun Jung, M.D. 1, Dae Sick Ryu, M.D. 2 Departments of 1 Internal Medicine, 2 Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea Background: In previous study, most patients with bronchial anthracofibrosis (BAF) were non-miners, and non-occupational old aged females. However, the clinical significance of BAF in patients with coal workers pneumoconiosis (CWP) is unknown. Methods: Among patients with CWP who transferred to our hospital for an evaluation of associated pulmonary diseases, 32 patients who had undergone a bronchofibroscopy (BFS) and chest computed tomography (CT) examination were evaluated for the association of the BAF using a retrospective chart review. Results: Nine of the 32 CWP patients (28%) were complicated with BAF. Four of the 16 simple CWP patients (25%) were complicated with BAF. According to the International Labor Organization (ILO) classification by profusion, 2 out of 3 patients in category 1, 1 out of 8 patients in category 2 and 1 out of 3 patients in category 3 were complicated with BAF. Five out of 16 complicated CWP patients were complicated with BAF. Three out of 7 patients in type A and 2 out of 5 patients in type C were complicated with BAF. CWP patients with BAF had significantly greater multiple bronchial thickening and multiple mediastinal or hilar lymph node enlargement than the CWP patients without BAF. There was no difference in the other clinical features between the CWP patients with BAF and those without BAF. Conclusion: Many CWP patients were complicated with BAF. The occurrence of BAF was not associated with the severity of CWP progression. Therefore, a careful evaluation of the airway with a bronchoscopy examination and chest CT is warranted for BAF complicated CWP patients who present with respiratory symptoms and signs, even ILO class category 1 simple CWP patients. Key Words: Pneumoconiosis; Bronchoscopy; Bronchial Anthracofibrosis 서 기관지탄분섬유화증 (bronchial anthracofibrosis) 은일 Address for correspondence: Bock Hyun Jung, M.D. Department of Internal Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, 415, Bangdongri, Sacheon-myun, Gangneung 210-711, Korea Phone: 82-33-610-3319, Fax: 82-33-641-8066 E-mail: jbh@gnah.co.kr Received: Nov. 4 2009 Accepted: Jan. 11, 2010 론 반적으로기관지내시경검사에서기관지점막이탄분에의한흑색및갈색의색소침착과함께기도벽의비후와기도협착이동반된경우를일컫는다. 이러한소견은탄광에근무한병력이없는대부분비흡연력을가진고령의여자환자에서주로발생하는것으로보고되었고결핵을동반하는경우가흔한것으로알려져있다 1,2. 석탄광에근무하는광부에서발생하는탄광부진폐증 (coal workers pneumoconiosis) 은흡입된분진중주로직경 0.5 5 μm 의작은호흡입자 (respiratory particle) 들이호흡세기관지 (respiratory bronchiole) 및폐실질에 67

MH Kim et al: Bronchial anthracofibrosis in coal workers pneumoconiosis 침착하여처음에는작은검은반점 (macule) 을형성하고점차진행하며주위폐실질에결절 (nodule) 을일으키고일부환자에서는진행성종괴성폐섬유증 (progressive massive fibrosis, PMF) 을일으키는반면, 큰분진입자는주로관성충돌 (inertial impact) 과침전 (sedimentation) 을통해상부기관지상피에침착되고직업성기관지염 (industrial bronchitis) 의원인이될수있다 3-6. 탄광부진폐증환자에서는흡입된탄가루 (coal dust) 가호흡세기관지주위의폐실질에침착시폐탄분증 (pulmonary anthracosis) 이라고불리며, 기관지경검사나조직검사상상부기관지점막에탄분침착을일으키는경우를기관지탄분증 (bronchial anthracosis) 이라고일컫는다 7,8. 탄광부진폐증환자에서이러한기관지점막의탄분침착으로인한기관지탄분증에대한보고는있어왔으나엽기관지나구역기관지같은내경이큰기관지점막에탄분침착과동반되어기도벽의비후와기도협착을일으키는기관지탄분섬유화증에대해서는잘알려져있지않다 6. 저자등은진폐증환자에서기도점막에탄분침착을동반한다발성기도협착을보이는기관지탄분섬유화증을임상에서자주경험하여탄광부진폐증환자를대상으로그임상적양상을알아보고자본연구를시행하였다. 대상및방법대상환자는과거력상석탄부광부로탄광에근무한직업력이있으면서흉부방사선사진상다발성폐음영이존재하여산재전문병원에서탄광부진폐증으로등록되어정기적인검진을받거나입원중인환자들로서내원시호흡기증상이악화되거나흉부방사선사진상에이상소견이새로발견되어본원호흡기내과에전원된환자들중에서 2000 년 1월부터 2005 년 12월까지흉부컴퓨터단층촬영과굴곡성기관지내시경검사를모두시행한환자들을대상으로의무기록과검사소견을후향적으로조사하였다. 국제노동기구 (International Labour Organization, ILO) 분류기준에 9 따라흉부방사선사진소견상흉부의결절성음영의크기에따라소음영은 p (<1.5 mm), q (1.5 3.0 mm), r (3.0 10 mm) 으로분류하고음영의조밀도 (profusion) 에따라개략분류로 1형 (1/0, 1/1, 1/2), 2형 (2/1, 2/2, 2/3), 3형 (3/2, 3/3, 3/+), 대음영 (A형, B형, C형 ) 으로분류하였다. 직경 1 cm 이상의큰음영을보이는경우 PMF 라정의하고 PMF 의유무에따라복합진폐증 (complicated pneumoconiosis) 과단순진폐증 (simple pneumoconiosis) 으로구분하였다. 폐병변을평가하기위해시행한흉부 CT는정맥조영제를투여하여완전흡기동안에 5 mm collimation, 5 mm 간격으로 HiSpeed scanner (General Electric Medical Systems, Milwaukee, WI, USA) 을이용하여촬영하였다. HRCT 는모든환자에서 1 mm collimation, 10 mm 간격으로시행하였다. 촬영된흉부 CT를통해 PMF, CT bronchus sign, 기관지벽비후 (bronchial wall thickening), 무기폐, 종격동및폐문부림프절비대, 폐결절의형태에대한평가를알아보았다. CT bronchus sign 은기관지내공기음영이 PMF 내부를따라보일때양성으로하였으며, 기관지벽의비후는기도벽이기관지직경의 15% 이상인경우로정의하였다 5,10. 종격동림프절의직경이 1.0 cm 이상, 폐문림프절이 0.5 cm 이상커졌을때로림프절비대로정의하였고림프절내에석화화유무를함께기록하였다. 기관지내경의협착은굴곡성기관지경검사소견상기관지내경이흡기및호기모두에서정상기관지보다 50% 이상좁아져있는경우로정의하였다. 기관지경검사상기관지점막에다발성탄분침착을보이는기관지탄분증환자중기관지점막에탄분침착과함께기관지협착이없거나한군데의국소적인기관지협착만을보이는경우를제외한양측기관지에서다발성탄분침착과함께두군데이상의기관지협착이동반된경우를기관지탄분섬유화증으로정의하였다 (Figure 1). 통계처리는통계분석프로그램인 SPSS 13.0 (SPSS Inc., Chicago, IL, USA) 을이용하여분석하였다. 흉부방사선상조밀도, 기관지탄분섬유화증동반군과비동반군의 CT 소견및임상소견의비교는 Chi-square test 을이용하여분석하였다. p값이 0.05 미만인경우통계적으로유의한차이가있다고판정하였다. 결과연구대상에적합한환자는모두 32명이었으며남자가 31명, 여자가 1명이었다. 평균나이는 64세 (47 79세) 였으며내원시주요호흡기증상은기침및객담악화 12명 (38%), 객혈 9명 (28%), 호흡곤란 7명 (22%), 흉통 3명 (9%), 기타 1명순이었다. 탄광부진폐증에동반된주요호흡기질환으로폐렴 8명 (25%), 폐암 8명 (25%), 활동성폐결핵 6명 (19%), progressive massive fibrosis (PMF) 악 68

Tuberculosis and Respiratory Diseases Vol. 68. No. 2, Feb. 2010 화 3명 (9%), 급성기관지염 3명 (9%), 기타 4명 ( 곰팡이덩이 1명, 농흉 1명, 기관지확장증 1명, 폐디스토마 1명 ) 이었다. 대상환자중 25명 (78%) 에서평균 31갑년 (pack-year) 의흡연력이있었으며 7명 (22%) 은비흡연자였다. 광산근무기간은단순진폐증환자들은평균 17년, 복합진폐증환자는 22년으로전체탄광부진폐증환자들은평균 20년 (5 40년 ) 간광부로근무한직업력을가지고있었다 (Table 1). 흉부방사선사진상소음영을보인단순진폐증환자 16명중음영의크기에따른분류시 p형 5명 (16%), q형 7명 (21%), r형 3명 (13%) 이었고, 대음영을보인복합진폐증환자 16명중 A형이 4명 (13%), B형이 7명 (21%), C형이 5명 (16%) 이었다. 굴곡성기관지경검사상기관지탄분증을보인환자는 전체대상환자 32명중 26명 (81%) 이었으며단순진폐증환자가 13명이었고복합진폐증환자가 13명이었다. 기관지점막에탄분침착과함께다발성기관지협착을보인기관지탄분섬유화증환자는모두 9명 (28%) 으로 4명의단순진폐증환자와 5명의복합진폐증환자에서기관지탄분섬유화증을동반하였다. 기관지탄분섬유화증이동반된환자들에서동반되지않은환자들에서보다임상적소견상호흡곤란을주증상으로호소하는경향이높았으나통계적유의성은없었다. 기존의연구 2,16 에서기관지탄분섬유화증과결핵과의연관성이높은것으로알려져있으나탄광부진폐증환자를대상으로한본연구에서기관지탄분섬유화증이있는환자 9명중결핵병력이있는환자는 4명 (44%) 이었고기관지탄분섬유화증이없는환자 23명중 8명 (35%) 에서결핵 Figure 1. 70-year-old man with coal workers pneumoconiosis associated with bronchial anthracofibrosis. (A) Contrast enhanced CT shows bronchial wall thickening due to enlarged lymph node and peribronchial fibrosis. (B) Lung setting on CT shows multiple p type nodules in the both upper lobes. (C) Flexible bronchoscopy shows bronchial narrowing with engorged mucosal vessel and anthracotic pigmentation in the right upper lobe bronchus. (D) Anthracotic pigmentation and bronchial stenosis is also noted in the right middle lobe bronchus. 69

MH Kim et al: Bronchial anthracofibrosis in coal workers pneumoconiosis Table 1. Demographics and clinical features of 32 patients with coal workers pneumoconiosis Simple Complicated Total CWP CWP CWP (n=16) (n=16) (n=32) Mean age, yr 63 65 64 Male/Female ratio 16/0 15/1 31/1 Duration of mining, yr 17 22 20 Smoking history Nonsmoker 3 4 7 Smoker (pack-year) 13 (30) 12 (33) 25 (31) Chief respiratory symptom Cough/Sputum (%) 5 7 12 (38) Hemoptysis (%) 5 4 9 (28) Dyspnea (%) 4 3 7 (22) Chest pain (%) 2 1 3 (9) Others (%) 0 1 1 (3) Associated pulmonary diseases Pneumonia 4 4 8 (25) Lung cancer 6 2 8 (25) Active tuberculosis 2 4 6 (19) PMF progression 0 3 3 (9) Nonspecific bronchitis 2 1 3 (9) Others 2 2 4 (13) CWP: coal workers penumoconiosis; PMF: progressive massive fibrosis. Table 2. The difference of clinical characteristics between coal workers pneumoconiosis with and without bronchial anthracofibrosis Clinical features CWP with BAF (n=9) CWP without BAF (n=23) Mean age, yr 66 63 Smoker 5 (40 pack-year) 20 (30 pack-year) Duration of miner, yr 22.5 19.4 History of tuberculosis 4 (44%) 8 (35%) Chief respiratory symptom Cough/sputum 4 (44%) 8 (35%) Dyspnea* 4 (44%) 3 (13%) Hemoptysis 1 (11%) 8 (35%) Other symptoms 0 (0%) 4 (17%) CWP: coal workers pneumoconiosis; BAF: bronchial anthracofibrosis. *p=0.053. 병력이있었다 (Table 2). 흉부컴퓨터단층촬영상기관지탄분섬유화증을동반 Table 3. The difference of the CT findings between coal workers pneumoconiosis with and without bronchial anthracofibrosis CT findings CWP with BAF (n=9) CWP without BAF (n=23) PMF 5 (56%) 11 (47%) CT bronchus sign 3 (33%) 7 (30%) Bronchial wall thickening* 9 (100%) 7 (30%) No bronchial thickening 0 16 (70%) 1 lobar or segmental 0 2 (9%) 2 3 lobar or segmental 3 (33%) 4 (17%) >4 lobar or segmental 6 (67%) 1 (4%) Atelectasis 3 (33%) 3 (13%) LN enlargement* 9 (100%) 17 (74%) No LN enlargement 0 6 (9%) Focal hilar 0 2 (9%) Focal mediastinal/hilar 4 (44%) 10 (43%) Both medisatinal/hilar 5 (56%) 5 (22%) LN calcification 8 (89%) 13 (57%) CWP: coal workers pneumoconiosis; PMF: progressive massive fibrosis; BAF: bronchial anthracofibrosis. *p<0.05. Table 4. The concurrence rate of bronchial anthracofibrosis complicated according to ILO classification of coal workers pneumoconiosis ILO class CWP with BAF (n=9) CWP without BAF (n=23) Simple CWP (16) 4 (25%) 12 (75%) Category 1 2 (40%) 3 (60%) Category 2 1 (13%) 7 (66%) Category 3 1 (33%) 2 (66%) Complicated CWP (16) 5 (31%) 11 (69%) Type A 0 (0%) 4 (100%) Type B 3 (43%) 4 (57%) Type C 2 (40%) 3 (60%) ILO: International Labor Organization; CWP: coal workers pneumoconiosis; BAF: bronchial anthracofibrosis. 하지않은환자들에비해기관지탄분섬유화증을동반한환자들에서다수의기관지벽의비후소견과종격동및폐문림프절의비대소견이유의하게높았다 (Table 3). 탄광부진폐증의진행정도에따른기관지탄분섬유화증의연관성을알아보기위해 ILO 분류법상의폐음영의크기와조밀도에따라탄광부진폐증을분류하였다. 단순 70

Tuberculosis and Respiratory Diseases Vol. 68. No. 2, Feb. 2010 진폐증환자 16명중 ILO 분류상 1형에해당하는 5명중 2명에서, 2형에해당되는 8명중 1명에서, 3형에해당되는 3명중 1명에서기관지탄분섬유화증이동반되었다. 복합진폐증환자 16명중 B형에해당하는 7명중 3명, C형에해당하는 5명중 2명에서기관지탄분섬유화증이동반되었다 (Table 4). 고찰우리나라의석탄광은대개고등급의석탄인무연탄 (anthracite) 광으로주로무연탄과함께석영, 규소등여러가지분진들의동반흡입에의하여탄광부진폐증이발생하는것으로알려져있다 11. 탄광부진폐증환자는모든기도에서분진의침착이발생할수있으나초기에는석탄반점 (coal macule) 이호흡세기관지를중심으로형성되어점차결절및폐기종으로진행되므로초기흉부방사선검사상소엽중심성결절 (centrilobular nodule) 의양상으로소음영이발생하기시작하여분진노출이계속되면점차진행되며, 일부환자에서는분진노출이중단되어도 PMF로진행되어복합진폐증을초래한다 12. 이러한탄광부진폐증환자에서기관지내시경검사를시행하면탄분이침착된기관지점막을흔히관찰할수있는데이렇게기관지점막에단순히탄분침착만생기는경우를기관지탄분증이라고일컫는다. 그러나이와는달리기관지점막에다발성탄분침착과함께기도벽에염증반응에의한기관지벽의비후와기도내강의협착을초래하는기관지탄분섬유화증에대한보고는분진노출의직업력이없는환자들에서오히려많이보고되어왔다 1,2,13. 우리나라에서보고된기관지탄분섬유화증의임상적특징은난방및취사용연료로사용한장작용나무연기에지속적으로노출된과거력이있는고령의여자환자에서대부분발견되며결핵이나폐렴과같은감염성질환의동반율이높고폐쇄성기도질환을일으키며일반적으로기도확장제나스테로이드에잘반응하지않는특징이있다 1,2,14. 이러한기관지탄분섬유화증의발생기전은아직잘알려져있지않은데임파선결핵이나기관지결핵과같은기도질환에의해국소부위의기관지협착과함께탄분침착이동반될수있으나 15,16, Kim 등 14 의보고에의하면양측기관지에광범위하게다발성으로탄분침착을동반한기도협착을일으키는전형적인기관지탄분섬유화증의발생기전은취사및난방용연료로사용하는나무연기에어린연령부터장기간노출시에기관지탄분섬유화 증을초래할수있다고주장하였다. 그래서저자들은탄광부에서석탄분진흡인에의한기관지탄분섬유화증의발생양상을알아보기위해국소적인기관지협착만을동반한환자들은제외하고양측성다발성기도협착과탄분침착을보이는환자만을기관지탄분섬유화증으로정의하였다. 본연구결과에서전체대상환자 32명중 23명 (72%) 에서기관지점막에탄분침착을보였고그중 9명 (28%) 에서기관지탄분섬유화증이발생하였다. 이러한결과는탄광부진폐증환자중적지않은환자에서기관지탄분섬유화증이발생할수있음을시사하며, 흡입된석탄분진이그발병기전에서한원인이될수있음을의미한다. 그러므로기관지탄분섬유화증은연료용나무나숯연기흡입외에도석탄가루의기도점막침착에대해기관지점막조직의과도한섬유화성염증반응의결과로발생할것으로사료된다. 그러나난방취사용나무연기를흡입한모든환자에서기관지탄분섬유화증이발생하는것이아닌것처럼석탄분진에노출된모든환자에서기관지탄분섬유화증이발생하지않은이유는아직잘알려져있지않다. 본연구결과에따르면탄광부진폐증의진행정도에따른분류시단순진폐증과복합진폐증환자사이에기관지탄분섬유화증발생률에차이가없었고, ILO 분류상 1형에서 3형까지소음영의조밀도증가에따른기관지탄분섬유화증의동반빈도가유의한차이가없었으며, PMF 의크기에따른 A형, B형및 C형사이에기관지탄분섬유화증의동반율에도유의한차이가없었다. 이러한연구결과는탄광부진폐증의진폐결절의발생기전과기관지탄분섬유화증의발생기전이상이함을시사하는결과이다. 석탄광부에서발생하는탄광부진폐증은분진의노출기간, 작업장분진의농도, 분진의화학적물리적특성, 각개인의면역학적및유전적감수성등여러가지에위험요소들에의해영향을받는다 17-20. 본연구결과에서나타난기관지탄분섬유화증의발생이탄광부진폐증의진행정도와직접적인상관성이없는것으로나타난연구결과는각질환의발생기전의차이에기인할수있다. 이러한결과를설명할수있는기전으로먼저탄광부진폐증과기관지탄분섬유화증을일으키는분진의입자의크기가차이가있을수있다. 탄광부진폐증을일으키는원인분진은주로크기가 0.5 5 m의직경을가진호흡성분진입자에의해발생하며이보다큰직경의분진에의해직업성기관지염을일으키는것으로알려져있어기관지탄분섬유화증의원인분진은이보다더클것으로 71

MH Kim et al: Bronchial anthracofibrosis in coal workers pneumoconiosis 사료된다. 그러나석탄광의작업장에서는다양한크기의분진입자가유사하게분포하므로탄광부진폐증과기관지탄분섬유화증이다르게발생할정도로선택적으로분진에노출되었다고보기는어렵다. 또한탄광부진폐증을일으키는분진과기관지탄분섬유화증을일으키는분진의종류가달라서이러한소견을보일수도있으나본환자들이모두석탄광부로일한직업력이같다는점에서이러한가능성도떨어진다. 이러한차이를설명할수있는또다른가능한기전은각개인의분진에대한감수성의차이가탄광부진폐증과기관지탄분섬유화증의발생양상에영향을미칠수있다. 특히호흡세기관지및폐실질에주로분진이침착되어폐손상을일으키는탄광부진폐증과달리주로엽기관지나구역기관지같은비교적큰직경의기관지에분진침착과함께기관지협착및기도벽의비후를초래하는기관지탄분섬유화증은같은환자내에서도기도의해부학적부위에따라분진에대한반응이달라서일어나는현상으로같은환자의기도내에서도해부학적위치에따라분진에대한감수성의차이때문에일어날수있다. 그러나이러한모든가능성은본연구결과가전체탄광부진폐증을무작위로표본조사한것도아니고대상환자의수가충분히많은것도아니며탄광부진폐증에동반된다른질환에대해검사를받기위해내원한일부환자만을대상으로후향적으로조사한연구이므로본연구결과만으로탄광부진폐증에동반된기관지탄분섬유화증의임상적의의나발생기전을추정하기는어려우며추후이에대한자세한연구가필요할것으로사료된다. 본연구에서기관지탄분섬유화증이동반된환자들의호흡기증상을비교분석을시도하였으나많은환자들이탄광부진폐증이외에도심혈관계질환, 폐결핵, 악성종양등다른중증질환을동반하였고모든환자에서폐기능검사가시행되지않아서기관지탄분섬유화증에의한임상증상을객관적으로평가하기는어려웠으며, 본연구결과상통계적으로유의하지않으나기관지탄분섬유화증이동반된환자에서호흡곤란을호소하는환자가많은경향을보였다. 대개탄광부진폐증환자중흉부방사선사진상소음영을보이는단순진폐증환자는호흡곤란이나폐기능의감소가뚜렷하지않은것으로알려져있으나 21 기관지탄분섬유화증이동반되면기관지내경의협착과기도벽의비후에의한기도의유순도의감소로운동시호흡곤란이뚜렷이증가될것으로추정된다. 그러므로임상에서흔히흉부방사선사진상단순진폐증을보여도 임상증상이나폐기능의감소가뚜렷한경우에는기관지내시경및흉부 CT 검사를시행하여기관지탄분섬유화증의동반유무와기도질환에대한적절한평가가필요할것으로사료된다. 결론적으로석탄광에근무한직업력을가진탄광부진폐증환자중일부환자에서석탄분진에의한기관지탄분섬유화증이동반될수있으며이러한기관지탄분섬유화증의발생은 ILO 분류에따른진폐증의진행정도에비례하지않으므로흉부방사선사진상의탄광부진폐증초기소견을보이더라도호흡곤란이나폐기능감소를보이는경우기관지내시경및흉부 CT를포함한적극적인검사를통해기관지탄분섬유화증과같은기도질환에대한적절한평가가필요할것으로사료된다. 참고문헌 1. Jang SJ, Lee SY, Kim SC, Lee SY, Cho HS, Park KH, et al. Clinical and radiological characteristics of non-tuberculous bronchial anthracofibrosis. Tuberc Respir Dis 2007;63:139-44. 2. Lee HS, Maeng JH, Park PG, Jang JG, Park W, Ryu DS, et al. Clinical features of simple bronchial anthracofibrosis which is not associated with tuberculosis. Tuberc Respir Dis 2002;53:510-8. 3. Ryder RC, Lyons JP, Campbell H, Gough J. Bronchial mucous gland status in coal workers' pneumoconiosis. Ann N Y Acad Sci 1972;200:370-80. 4. Chong S, Lee KS, Chung MJ, Han J, Kwon OJ, Kim TS. Pneumoconiosis: comparison of imaging and pathologic findings. Radiographics 2006;26:59-77. 5. Remy-Jardin M, Remy J, Farre I, Marquette CH. Computed tomographic evaluation of silicosis and coal workers' pneumoconiosis. Radiol Clin North Am 1992;30:1155-76. 6. Voisin C, Macquet L, Lenoir L, Houcke M, Savinel E, Muchery-Piat G. Bronchial involvement in diverse stages of pneumoconiosis in coal miners. Bronches 1965;15:449-61. 7. Mulliez P, Billon-Galland MA, Dansin E, Janson X, Plisson JP. Bronchial anthracosis and pulmonary mica overload. Rev Mal Respir 2003;20(2 Pt 1):267-71. 8. Huttner H, Beyer M, Bargon J. Charcoal smoke causes bronchial anthracosis and COPD. Med Klin (Munich) 2007;102:59-63. 9. International Labour Office. International classification of radiographs of pneumoconiosis. 1st ed. Geneva: International Labour Office; 2001. 72

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