Coal Worker’s Pneumoconiosis ( CWP )

DR.S.H.HASHEMI

TERMINOLOGY

COAL is used as a basic fuel for numerous industries requiring a source of heat.

Coal dust containe Silica, Kaolin, PAH, Quarts, Carbon .

Pneumoconiosis : the radiologic or pathologic appearances relating to the accumulation of lung dust deposits and the associated tissue reactions.

Clinical effects of coal dust : Acute effects: acute drop in FEV1 ( months to years ).

Chronic effects: CWP (≥ 10-20 y )

Term CWP: a chronic, irriversible disease with insidious onset A heavy coal dust burden is required to induce CWP Rarely in those who have spent fewer than 10-20 years

under ground.

LUNG PATHOLOGY( Pigmented lesions )

Accumulation of dark pigment(coal dust) in alveolar MQ >> MQ activity >> inflamatory changes >> product Reticolin >> MACULE (primary lesion in CWP ).

LUNG PATHOLOGY( Black lung )

MACULE Destract of alveolar walls Emphysema Collagen Scar Dust deposition Massive lesions Cavitation Black liquid

Location of macule Primary lesion in upper lobe , upper segment lower lobe .

Clinical manifestation Simple CWP: lesions in CXR <10 mm diameter asymptomatic

Clinical manifestation . . .

Complicated CWP (PMF): lesions in CXR >10 mm diameter

Clinical manifestation . . . Complicated CWP (PMF):

Chronic Bronchitis: chronic couph and productive sputum

Emphysema

Silicosis:(due to silica)CWP and Silicosis often see in coal miner Silicosis is pathologically distinct from CWP Two disorders often cannot distinguished radiographically

Mycobactrial infection: (TB ,other mycobactrial dx due to silica )

Caplan Sx (Rheumatoid pneumoconiosis ): CWP + RA(joint disorder , rheumatiod nodule )

Malignancy: Lung cancer, gastric cancer, bladder, skin, scrotum

Pathologic classification of coal mine dust-induced changes

Imaging

CXR: Simple CWP: lesions <10 mm diameter(3-10 mm), round or irregular Complicated CWP (PMF): lesions >10 mm diameter

CXR is insensitive to early pathologic intrestitial and emphysematous changes.which may be found pathologically or on HRCT with normal routin CXR.

May by visible abnormal in CXR whitout clinical disease (preclinical stage) if remove Pt from exposure decrease progression of dx .

if CWP whit silica exposure in CXR hilar LN calcification

CXR . . .

Complicated CWP (PMF)

Complicated CWP (PMF)

Emphysema PMF

Cavitation

PMF

Emphysema

Caplan Sx (Rheumatoid pneumoconiosis )

Imaging . . . CT scan: for pneumoconiotic nodules and PMF, when they

were not apparent on routin CXR .

HRCT: high sensitive for emphysema in early stage .

Gallium scan: increased activity but not specific .

MRI: no utility

Imaging . . .

PFT: Simple CWP: no significant abnormality

Comlicated CWP (PMF): restrictive or mixed pattern DLCo

ABG: hypoxia, hyper capnia

Prognosis

Simple CWP: benign course

Complicated CWP: mild to sever respiratory symptoms and impairment

Prevention

1° prevention: decrease exposure Dilution ventilation Dust suppression Increase fresh air Water spray near the cutting head Respirator

Prevention . . . 2° prevention:

Examination CXR Spirometery (decrease ≥ 15% FEV1 from baseline is

significant )