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There are three basic criteria for the diagnosis of CWP:
1. Chest radiography consistent with CWP
2. An exposure history to coal dust (typically underground coal mining) of sufficient amount and latency
3. Exclusion of alternative diagnoses (mimics of CWP)
Symptoms and pulmonary function testing relate to the degree of respiratory impairment but are not part of the diagnostic criteria. As noted above, the chest X-ray appearance for CWP can be virtually indistinguishable from silicosis. Chest CT, particularly high-resolution scanning (HRCT), are more sensitive than plain X-ray for detecting the small round opacities.
There are three key elements to the diagnosis of silicosis. First, the patient history should reveal exposure to sufficient silica dust to cause this illness. Second, chest imaging (usually chest x-ray) that reveals findings consistent with silicosis. Third, there are no underlying illnesses that are more likely to be causing the abnormalities. Physical examination is usually unremarkable unless there is complicated disease. Also, the examination findings are not specific for silicosis. Pulmonary function testing may reveal airflow limitation, restrictive defects, reduced diffusion capacity, mixed defects, or may be normal (especially without complicated disease). Most cases of silicosis do not require tissue biopsy for diagnosis, but this may be necessary in some cases, primarily to exclude other conditions.
For uncomplicated silicosis, chest x-ray will confirm the presence of small ( 1 cm) occurs from coalescence of small opacities, particularly in the upper lung zones. With retraction of the lung tissue, there is compensatory emphysema. Enlargement of the hilum is common with chronic and accelerated silicosis. In about 5–10% of cases, the nodes will calcify circumferentially, producing so-called "eggshell" calcification. This finding is not pathognomonic (diagnostic) of silicosis. In some cases, the pulmonary nodules may also become calcified.
A computed tomography or CT scan can also provide a mode detailed analysis of the lungs, and can reveal cavitation due to concomitant mycobacterial infection.
The best way to prevent silicosis is to identify work-place activities that produce respirable crystalline silica dust and then to eliminate or control the dust ("primary prevention"). Water spray is often used where dust emanates. Dust can also be controlled through dry air filtering.
Following observations on industry workers in Lucknow (India), experiments on rats found that jaggery (a traditional sugar) had a preventive action against silicosis.
According to the American Thoracic Society (ATS), the general diagnostic criteria for asbestosis are:
- Evidence of structural pathology consistent with asbestosis, as documented by imaging or histology
- Evidence of causation by asbestos as documented by the occupational and environmental history, markers of exposure (usually pleural plaques), recovery of asbestos bodies, or other means
- Exclusion of alternative plausible causes for the findings
The abnormal chest x-ray and its interpretation remain the most important factors in establishing the presence of pulmonary fibrosis. The findings usually appear as small, irregular parenchymal opacities, primarily in the lung bases. Using the ILO Classification system, "s", "t", and/or "u" opacities predominate. CT or high-resolution CT (HRCT) are more sensitive than plain radiography at detecting pulmonary fibrosis (as well as any underlying pleural changes). More than 50% of people affected with asbestosis develop plaques in the parietal pleura, the space between the chest wall and lungs. Once apparent, the radiographic findings in asbestosis may slowly progress or remain static, even in the absence of further asbestos exposure. Rapid progression suggests an alternative diagnosis.
Asbestosis resembles many other diffuse interstitial lung diseases, including other pneumoconiosis. The differential diagnosis includes idiopathic pulmonary fibrosis (IPF), hypersensitivity pneumonitis, sarcoidosis, and others. The presence of pleural plaquing may provide supportive evidence of causation by asbestos. Although lung biopsy is usually not necessary, the presence of asbestos bodies in association with pulmonary fibrosis establishes the diagnosis. Conversely, interstitial pulmonary fibrosis in the absence of asbestos bodies is most likely not asbestosis. Asbestos bodies in the absence of fibrosis indicate exposure, not disease.
Positive indications on patient assessment:
- Shortness of breath
- Chest X-ray may show a characteristic patchy, subpleural, bibasilar interstitial infiltrates or small cystic radiolucencies called honeycombing.
Pneumoconiosis in combination with multiple pulmonary rheumatoid nodules in rheumatoid arthritis patients is known as Caplan's syndrome.
Chest radiography is usually the first test to detect interstitial lung diseases, but the chest radiograph can be normal in up to 10% of patients, especially early on the disease process.
High resolution CT of the chest is the preferred modality, and differs from routine CT of the chest. Conventional (regular) CT chest examines 7–10 mm slices obtained
at 10 mm intervals; high resolution CT examines 1-1.5 mm slices at 10 mm
intervals using a high spatial frequency reconstruction algorithm. The HRCT therefore provides approximately 10 times more resolution than the conventional CT chest, allowing the HRCT to elicit details that cannot otherwise be visualized.
Radiologic appearance alone however is not adequate and should be interpreted in the clinical context, keeping in mind the temporal profile of the disease process.
Interstitial lung diseases can be classified according to radiologic patterns.
Investigation is tailored towards the symptoms and signs. A proper and detailed history looking for the occupational exposures, and for signs of conditions listed above is the first and probably the most important part of the workup in patients with interstitial lung disease. Pulmonary function tests usually show a restrictive defect with decreased diffusion capacity (DLCO).
A lung biopsy is required if the clinical history and imaging are not clearly suggestive of a specific diagnosis or malignancy cannot otherwise be ruled out. In cases where a lung biopsy is indicated, a trans-bronchial biopsy is usually unhelpful, and a surgical lung biopsy is often required.
There is no cure available for asbestosis. Oxygen therapy at home is often necessary to relieve the shortness of breath and correct underlying low blood oxygen levels. Supportive treatment of symptoms includes respiratory physiotherapy to remove secretions from the lungs by postural drainage, chest percussion, and vibration. Nebulized medications may be prescribed in order to loosen secretions or treat underlying chronic obstructive pulmonary disease. Immunization against pneumococcal pneumonia and annual influenza vaccination is administered due to increased sensitivity to the diseases. Those with asbestosis are at increased risk for certain cancers. If the person smokes, quitting the habit reduces further damage. Periodic pulmonary function tests, chest x-rays, and clinical evaluations, including cancer screening/evaluations, are given to detect additional hazards.
Health care professionals are at risk of occupational influenza exposure; during a pandemic influenza, anyone in a close environment is at risk, including those in an office environment.
The diagnosis of RA was formerly based on detection of rheumatoid factor (RF). However, RF is also associated with other autoimmune diseases. The detection of anti-CCP is currently considered the most specific marker of RA. The diagnosis of rheumatoid lung disease is based on evaluation of pulmonary function, radiology, serology and lung biopsy. High resolution CT scans are preferred to chest X-rays due to their sensitivity and specificity.
Associated doctors to diagnosis this properly would be a Rheumatologists or Pulmonologist.
Within a physical examination doctors could find possible indications, such as hearing crackles (rales) when listening to the lungs with a stethoscope. Or, there may be decreased breath sounds, wheezing, a rubbing sound, or normal breath sounds. When listening to the heart, there may be abnormal heart sounds. Bronchoscopic, video-assisted, or open lung biopsy allows the histological characterization of pulmonary lesions, which can distinguish rheumatoid lung disease from other interstitial lung diseases.
The following tests may also show signs of rheumatoid lung disease:
- Chest x-ray may show:
- pleural effusion
- lower zone predominant reticular or reticulonodular pattern
- volume loss in advanced disease
- skeletal changes, e.g. erosion of clavicles, glenohumeral erosive arthropathy, superior rib notching
- Chest CT or HRCT features include:
- pleural thickening or effusion
- interstitial fibrosis
- bronchiectasis
- bronchiolitis obliterans
- large rheumatoid nodules
- single or multiple
- tend to be based peripherally
- may cavitate (necrobiotic lung nodules)
- cavitation of a peripheral nodule can lead to pneumothorax or haemopneumothorax.
- follicular bronchiolitis
- small centrilobular nodules or tree-in-bud
- rare
- Caplan syndrome
- Echocardiogram (may show pulmonary hypertension)
- Lung biopsy (bronchoscopic, video-assisted, or open), which may show pulmonary lesions
- Lung function tests
- Needle inserted into the fluid around the lung (thoracentesis)
- Blood tests for rheumatoid arthritis
In 2013 CWP resulted in 25,000 deaths down from 29,000 deaths in 1990. Between 1970–1974, prevalence of CWP among US coal miners who had worked over 25 years was 32%; the same group saw a prevalence of 9% in 2005–2006.
The exact cause of rheumatoid lung disease is unknown. However, associated factors could be due largely to smoking. Sometimes, the medicines used to treat rheumatoid arthritis, especially methotrexate, may result in lung disease.
Prevention's:
- Stop smoking: Chemicals found in cigarettes can irritate already delicate lung tissue, leading to further complications.
- Having regular checkups: The doctor could listen to lungs and monitor breathing, because lung problems that are detected early can be easier to treat.
Tuberculosis is a lung disease endemic in many parts of the world. Health care professionals and prison guards are at high risk for occupational exposure to tuberculosis, since they work with populations with high rates of the disease.
Pneumoconiosis is an occupational lung disease and a restrictive lung disease caused by the inhalation of dust, often in mines and from agriculture.
In 2013, it resulted in 260,000 deaths, up from 251,000 deaths in 1990. Of these deaths, 46,000 were due to silicosis, 24,000 due to asbestosis and 25,000 due to coal workers pneumoconiosis.
The nodules may pre-date the appearance of rheumatoid arthritis by several years. Otherwise prognosis is as for RA; lung disease may remit spontaneously, but pulmonary fibrosis may also progress.
Once tuberculosis has been excluded, treatment is with steroids. All exposure to coal dust must be stopped, and smoking cessation should be attempted. Rheumatoid arthritis should be treated normally with early use of DMARDs.
A fiber cannot be identified or ruled out as asbestos, either using the naked eye or by simply looking at a fiber under a regular microscope. The most common methods of identifying asbestos fibers are by using polarized light microscopy (PLM) or transmission electron microscopy (TEM). PLM is less expensive, but TEM is more precise and can be used at lower concentrations of asbestos.
If asbestos abatement is performed, completion of the abatement is verified using visual confirmation and may also involve air sampling. Air samples are typically analyzed using phase contrast microscopy (PCM). PCM involves counting fibers on a filter using a microscope. Airborne occupational exposure limits for asbestos are based on using the PCM method.
The American Conference of Governmental Industrial Hygienists has a recommended Threshold Limit Value (TLV) for asbestos of 0.1 fibers/mL over an 8-hour shift. OSHA in the United States and occupational health and safety regulatory jurisdictions in Canada use 0.1 fibers/mL over an 8-hour shift as their exposure limits.
Mineral dust airway disease is due to inhaled mineral dust causing fibrosis and narrowing of primarily the respiratory bronchioles. It is distinct from pneumoconiosis which is due to lung tissue fibrosis but shares the same cause.
Progressive Massive Fibrosis (PMF), characterized by the development of large conglomerate masses of dense fibrosis (usually in the upper lung zones), can complicate silicosis and coal worker's pneumoconiosis. Conglomerate masses may also occur in other pneumoconioses, such as talcosis, berylliosis (CBD), kaolin pneumoconiosis, and pneumoconiosis from carbon compounds, such as carbon black, graphite, and oil shale. Conglomerate masses can also develop in sarcoidosis, but usually near the hilae and with surrounding paracitricial emphysema.
The disease arises firstly through the deposition of silica or coal dust (or other dust) within the lung, and then through the body's immunological reactions to the dust.
According to the International Labour Office (ILO), PMF requires the presence of large opacity exceeding 1 cm (by x-ray). By pathology standards, the lesion in histologic section must exceed 2 cm to meet the definition of PMF. In PMF, lesions most commonly occupy the upper lung zone, and are usually bilateral. The development of PMF is usually associated with a restrictive ventilatory defect on pulmonary function testing. PMF can be mistaken for bronchogenic carcinoma and vice versa. PMF lesions tend to grow very slowly, so any rapid changes in size, or development of cavitation, should prompt a search for either alternative cause or secondary disease.
Diseases commonly associated with asbestos include:
- Asbestosis: Progressive fibrosis of the lungs of varying severity, progressing to bilateral fibrosis, honeycombing of the lungs on radiological view with symptoms including rales and wheezing. Individuals who have been exposed to asbestos via home, environment, work should notify their doctors about exposure history.
- Asbestos warts: caused when the sharp fibers lodge in the skin and are overgrown causing benign callus-like growths.
- Pleural plaques: discrete fibrous or partially calcified thickened area which can be seen on X-rays of individuals exposed to asbestos. Although pleural plaques are themselves asymptomatic, in some patients this develops into pleural thickening.
- Diffuse pleural thickening: similar to above and can sometimes be associated with asbestosis. Usually no symptoms shown but if exposure is extensive, it can cause lung impairment.
- Pneumothorax: Some reports have also linked the condition of pneumothorax to asbestos related diseases.
It is important to consult a doctor, particularly if the following symptoms develop: shortness of breath, wheezing or hoarseness, persistent cough that worsens over time, blood in fluid coughed up, pain or tightening in chest, difficulty swallowing, swelling of neck or face, decreased appetite, weight loss, fatigue or anemia.
Initially, the disease appears as alveolitis, and then progresses to emphysema.
Patients may develop pneumothorax (collapsed lung).
Bauxite pneumoconiosis, also known as Shaver's disease, corundum smelter's lung, bauxite lung or bauxite smelters' disease, is a progressive form of pneumoconiosis usually caused by occupational exposure to bauxite fumes which contain aluminium and silica particulates.
It is typically seen in workers involved in the smelting of bauxite to produce corundum.
The barium particles can be seen as opaque shadows on the chest X-rays of people with baritosis. However, being a benign condition, it neither interferes with lung function nor causes symptoms other than a mild cough.
After exposure to barium dust ceases, the X-ray abnormalities gradually resolve.
Prevention measures include avoidance of the irritant through its removal from the workplace or through technical shielding by the use of potent irritants in closed systems or automation, irritant replacement or removal and personal protection of the workers.
In order to better prevent and control occupational disease, most countries revise and update their related laws, most of them greatly increasing the penalties in case of breaches of the occupational disease laws. Occupational disease prevention, in general legally regulated, is part of good supply chain management and enables companies to design and ensure supply chain social compliance schemes as well as monitor their implementation to identify and prevent occupational disease hazards.