Presented by: Najafi AZ, MD

 Respiratory tract a common site of occupational injury  Two sites: ◦ Airways ◦ Parenchyma  Site of injury depends on: ◦ Gas solubility ◦ Particle size

 History  Physical exam  Pulmonary function tests: ◦ Spirometry ◦ Body plethysmography ◦ DLCO  Imaging: ◦ Chest X ray ◦ HRCT

 Short-term exposure to high concentration of gases, fumes, or mists  Generally as an accident  Irritation of membranes  Chemical pneumonitis  ARDS  Chmicals: ◦ Formaldehyde ◦ Cadmium salts ◦ chlorine

 Upper respiratory tract irritation  Cough  Stridor  Hoarseness  Wheezing  PFT: normal, obstructive, mixed  Chest X ray: normal to pulmonary edema

 Reversible airway obstruction, with airway inflammation and bronchial hyperresponsiveness as a consequence of occupational exposures

Work-related asthma(WRA) Occupational asthma caused by work(OA) Sensitizer induced asthma Irritant induced asthma Work- exacerbated asthma

 Sensitizer-induced ◦ Type 1 immune reaction (IgE) ◦ Latent period for sensitization ◦ In a percent of workers  Irritant-induced ◦ RADS  Without latency  Exposure to a high concentration  In most workers

 History: ◦ Hx of dyspnea (exertional), cough, in an episodic mode, night symptoms  Physical exam ◦ wheezing  PFT ◦ Spirometry: normal or obstructive ◦ BD test: mostly responsive  Chest X ray ◦ Not helpful

Current health (during the last 4 weeks) If you run or climb stairs fast do you ever: Cough? Wheeze? Get tight in the chest? Yes/no Is you sleep ever broken by: Wheeze? Difficulty with breathing? Yes/no Do you ever wake up in the morning with: wheeze? Difficulty with breathing? Yes/no Do you ever wheeze: If you are in a smoky room? If you are in a very dusty place? Yes/no Screening questionnaire

I. Occupational symptoms. II. Serial P.E.F III. Serial spirometry IV. Challenge test

 Reduction or elimination of exposure  Beta agonists  corticosteriods

1. Substitution 2. Ventilation 3. Change of procedure 4. Restriction of employment 5. Free from smoke 6. Accidental education 7. Environmental screening 8. Protective devices

 A type of O-ILDs.  Due to inhalation and deposition of mineral dust within lung parenchyma.  Induce tissue reaction  May cause disruption of alveolar architecture or collagen fibrosis.

 Deposition of mineral dusts in lung tissue.  Presence of parenchymal tissue reaction  Positive chest x-ray findings  PFT may be abnormal depending on the stage and severity and complications.

 Benign: ◦ Asymptomatic ◦ Normal spirometric findings  Collageneous: ◦ Symptomatic ◦ Abnormal spirometric findings

 Sufficient and reasonable exposure. (intensity and duration)  Positive chest x-ray findings (good quality is required)  No other concomitant diseases that mimic pneumoconiosis.

 Silicosis  Asbestosis  Coal-workers ’ pneumoconiosis

Silicosis

 A collagenous pneumoconiosis caused by inhalation of respirable (0.2 – 10 µ m ) free crystalline silicon dioxide ( SiO2 ).  Chronic diffuse interstitial fibronodular lung disease.  High-dose and long-time inhalation is required.  A strict dose-response relationship is present  Cumulative exposure  Intensity × duration

 Removal of stone  Hard rock mining  Tunnel drilling  Stone quarrying  Processing stone or sand  Stone crushing  Granite carving

Minning Foundry work Sand blasting Ceramics

 Abrasive use of silica or sand  Abrasive blasting  Foundry casting  Knife sharpening  Production of fine silica powder

 Utilization of sand or silica powder ◦ Glass manufacture ◦ Plastic manufacture ◦ Paint manufacture ◦ Pottery ◦ Ceramic manufacture ◦ Construction work

 Chronic bronchitis  Emphysema  Silicosis  Tuberculosis  Lung cancer  Collagen vascular diseases

 Chronic simple ( classic ) silicosis  Chronic complicated ( PMF ) silicosis  Accelerated silicosis  Acute silicosis

 Moderate long-time exposure (at least 10 yr) to less than 30% quartz  Symptoms and signs: ◦ Mostly asymptomatic ◦ Chronic productive cough or DOE due to chronic bronchitis ◦ Progressive DOE and dry cough (late finding) ◦ Ph. exam normal or crackles ◦ PFT: normal or restrictive (mainly) obstructive or mixed pattern ◦ CXRay: small (<1 cm), round nodules predominantly in upper lobes, hilar lymphadenopathy and calcification

 Progressive massive fibrosis  Tuberculosis(3-fold to 20-fold)  Pulmonary and extrapulmonary  Typical and atypical mycobacteria  Immune-mediated  Scleroderma (m/c)  SLE, RA, …  Renal (GN, nephrotic syndrome)(usually in heavy exposure)  Lung cancer  Fungal diseases  Cryptococcus  Blastomycosis  coccidiopmycosis

Silicosis Calcified lymph nodes Upper lobe nodules

Silica exp. & TB  Incidence of TB is greater in accelerated or acute Silicosis  Silica exp. in the absence of silicosis is risk factor for TB  Silica exp. : Risk for TB  Radiographic changes in silicosis frequency of TB frequency of TB  Silica exp. & TB: Death 4 yrs earlier than TB alone

Cont. TB & silicosis Cont. TB & silicosis  Dx : rapid worsening of CXR, decline in lung function suspicion for TB  regular PPD skin test (yearly )  PPD(+) without active TB, indicated at least 1 yr INH prophylaxis.

Diagnosis Diagnosis 1-History of silica exp. 2-Chest radiography consist with silicosis. 3-R/O other illness that mimic silicosis.  HRCT & Lung biopsy (open) if …

Prevention  Product substitution of silica with less toxic particles  Engineering control of dust concentration  Appropriate use of respiratory protective devices  Medical screening: questionnaire, CXR, spirometry

WHO recommendation:  CXR : At baseline, after 2-3 years of exposure, At baseline, after 2-3 years of exposure, then every 2-5 years. then every 2-5 years.  Spirometry + questionnaire : At baseline, then annually or at the same frequency as CXR. At baseline, then annually or at the same frequency as CXR.

Management  Diagnosis of silicosis Remove  Regular CXR and PPD skin test  Steroid helpful in Acute S. or autoimmune dis. (+ INH prophylaxis)  Whole lung lavage for acute silicosis ?  Tetrandrine  Lung trasplantation

 Crystalline silica (quartz, cristobalite) is carcinogen (group 1 IARC)  Silicosis is associated with autoimmune disease (RA, SLE, Scleroderma)

 Pipe covering  Asbestos cloth  Cements  Roofing materials

 Clinical presentation: exertional dyspnea,, cough, chest pain, clubbing X Ray: reticular veiling lower lobes, ground glass  pleural changes, PMF in mixed exposure,  Lung fx: restrictive, diffusion ↓, hypoxemia,

 Coal worker's pneumoconiosis (CWP) can be defined as the accumulation of coal dust in the lungs and the tissue's reaction to its presence:  simple CWP (SCWP)  pulmonary massive fibrosis (PMF)

 Radiology: nodular veiling upper lung  zones, nodules > 1 cm indicative of PMF  Lung fx: normal – simple type restrictive – complicated type  Prognosis: simple type – good  complicated type – cardio-respiratory failure

 Immunologically mediated inflammatory disease of lung parenchyma caused by some organic dusts

 History ◦ Acute: cough, fever, chills, malaise, dyspnea after an acute exposure ◦ Chronic  Physical exam ” ◦ Basilar inspiratory crackles  PFT: ◦ Restrictive or mixed pattern, low DLCO  CXray: ◦ normal, reticulonodular pattern, infiltration

 Avoidance of exposure  Corticosteroids

OCCUPATIONAL LUNG DISEASES ARE PREVENTABLE

Complex exposures