English name: Silicosis or Pneumonoultramicroscopicsilicovolcanoconiosis
Pneumoconiosis due to long-term excessive inhalation of rock dust containing crystalline free silicon dioxide
2 Causes of the disease edited
Silicon is widely distributed in nature, and about 95% of the ore is pure quartz in various forms (containing more than 97% free silicon dioxide); silicon is also a major component of the earth's crust. So in mining, quarrying, excavation tunnels, engaged in rock drilling, blasting and other operations of the workers, exposure to dust opportunities; rolling stone, crushing, manufacturing glass, enamel and refractory materials, mixing materials, foundry industry in the milling, sand, sand, modeling, masonry, sandblasting and sand clearing and other types of work, are in contact with silica dust (commonly known as silica dust) opportunities. Quartz is usually used to represent free silica. Whether exposure to quartz depends on a number of factors, in addition to its physical and chemical properties, the free silica content of the dust, the concentration of dust in the air, the size of the dust particles, the contact time, as well as the body's defenses, all affecting the occurrence of silicosis and its severity. Generally speaking, containing more than 80% of free silica dust, often in the lungs caused by typical nodule-based diffuse collagen fiber changes, the disease progresses faster, and easy to fusion. When free silica is less than 80%, the lesions are less typical and the disease progresses more slowly. When it is lower than 10%, it mainly causes interstitial fibrous changes, develops more slowly, and is classified as other pneumoconiosis. A large amount of dust containing high levels of free silica is inhaled into the lungs and often cannot be removed from the respiratory tract in a timely and complete manner. Sometimes, although there is no sign of silicosis, but after a number of years after leaving the work of silicosis, often referred to as "late-onset silicosis"; early silicosis patients even if they leave the dust work, the disease will continue to develop, such as no comorbidities, the patient can survive for a longer period of time, but often the loss of the ability to work. Therefore, in order to protect the health of workers, China has stipulated that the maximum permissible concentration of free silica dust in the air of the workshop containing more than 10% is 2mg/m3; when it exceeds 80%, it is 1mg/m3. Where this requirement can be met, silicosis will not occur. In addition, the respiratory system has chronic lesions, such as chronic rhinitis, chronic bronchitis, emphysema, tuberculosis, etc., the patient's defense function is poorer, the airway mucus - cilia activity is weaker, in the same environment than the health of the person is more prone to develop.
3Clinical manifestationsEdit
Silicosis patients can generally be asymptomatic or asymptomatic in the early stage, with the development of the lesion, the symptoms increase, the main manifestations are as follows:
(a) Coughing, sputum cough due to dust irritation and respiratory inflammation, or reflex cough. The degree of coughing and the amount of sputum is closely related to bronchitis or secondary infection of the lungs, but is not consistent with the degree of silicosis. A few patients may have bloody sputum. If there is repeated massive hemoptysis, then the combination of tuberculosis or bronchiectasis should be considered.
(2) Chest pain 40% to 60% of patients have pins and needles chest pain. Most of them are located in one or both sides of the upper middle part of the chest, which is not related to respiration, position and labor, and often occurs on rainy and cloudy days and when the climate is changing.
(3) The degree of chest tightness and shortness of breath is related to the scope and nature of the lesion. If the lesion is extensive and progresses rapidly, the shortness of breath is obvious and increases progressively. This is due to extensive fibrosis of lung tissue, massive destruction of alveoli, bronchial stenosis as well as pleural thickening and adhesions, resulting in ventilation and air exchange function impairment. Patients may also have dizziness, fatigue, palpitations, loss of appetite and other symptoms.
Early silicosis patients often have no abnormal findings on physical examination. In severe silicosis, due to the fusion of nodules and contraction of lung tissue, there may be airway displacement and turbid percussion.
4Pathologic description editing
The basic lesion of silicosis is the formation of silicosis nodules and extensive fibrosis of the interstitium, which develops as follows:
(1) Formation of silicosis nodules Typical silicosis nodules are concentrically arranged collagen fibers that resemble the cut surface of an onion (Figure 12-2). There may be silica dust in the middle of the collagen fibers, and the silica dust may flow with the tissue fluid to form new nodules elsewhere. Because of the slow action of silica dust, silicosis can continue to progress after removal from silica dust operations. Silicosis nodules are grayish-white in color, with a diameter of about 0.3 to 0.8 mm. Multiple small nodules may merge to form a large nodule, or form a large mass, which is mostly found in the two upper lungs. If the diameter is more than 1mm, round or round-like shadow can be shown on X-ray chest film. Siliceous nodules often form by encircling blood vessels, so that the blood vessels are squeezed and the blood supply is poor, causing necrosis and vitrification of the collagen fibers. The necrotic tissue is expelled through the bronchial tubes, forming cavities. Silicosis cavities are generally small and rare. It is mostly found in the most severe part of the fusion lesion.
(2) Interstitial changes in the lungs, alveolar septum and blood vessels, a large number of dust deposits around the bronchioles, as well as dust cell aggregation, resulting in thickening of the alveolar septum. Later, fibrous tissue proliferates and lung elasticity decreases. Small nodules fuse and enlarge, causing inter-nodal alveolar atrophy. Compensatory emphysema may occur around the fibrous masses, and even alveoli may form. Perivascular fibrous tissue proliferation as well as silicotic nodules encircle the blood vessels, which are twisted and deformed. At the same time, due to the fibrosis of the vessel wall itself, the lumen narrows and even occludes. The damage to small arteries is more pronounced. The pulmonary capillary bed is reduced, contributing to increased resistance to blood flow and increasing the burden on the right heart. If the lung lesions continue to develop, hypoxia and spasm of small pulmonary arteries can lead to pulmonary hypertension to pulmonary heart disease. As a result of nodular fibrosis around the bronchi at all levels, or due to the contraction of the mass fibers, the bronchi are compressed, twisted and distorted, and the lumen is narrowed, resulting in piston-like ventilation obstruction, leading to hyperinflation of the alveoli to which it belongs, and then rupture of alveoli and the formation of emphysema. Around the large mass of fibrosis is the whole lobular type of emphysema, and around the respiratory fine bronchioles is the lobular central type of emphysema. Emphysema is most often found in the middle and lower lobes of both lungs. Sometimes the lumen is completely occluded, leaving the alveoli to which it belongs atrophied or lobular atelectasis. Fine bronchial tubes may be dilated to varying degrees.
(3) Lymphatic system changes in the lungs Dust cells lend their amoebic movement into the lymphatic system, causing fibrous tissue proliferation in the lymph nodes, especially the hilar lymph nodes appear enlarged and sclerotic. This is followed by lymphatic reflux, where the dust cells accumulate with the lymphatic fluid from the hilum to the periphery and reach the pleura.
(iv) Pleural changes Stagnation of dust cells and silica dust on the pleura may also cause fibrosis and formation of silica nodules; thickening and adhesion of the pleura. In severe cases, when alveoli in the diaphragmatic pleura rupture, spontaneous pneumothorax is often limited because of pleural adhesions.
5Diagnostic notes edited
Diagnostic basis
①History of dust exposure, including the free silica content of raw materials and finished products, the concentration of dust in the production environment, the size of the dust particles, the method of production operations and protective measures (including personal protection);
②Detailed occupational history of the patient and his or her past health condition;
3Clinical symptoms, Signs and X-ray examination;
④Past and ongoing morbidity of workers of the same job type.
Specific criteria
(I) X-ray examination In addition to the above, the diagnosis of anthrasilicosis is mainly based on the chest X-ray. China announced the "Diagnostic Criteria and Treatment Principles of Pneumoconiosis" in December 1986, in which the X-ray diagnostic criteria of pneumoconiosis are applicable to all kinds of pneumoconiosis legally recognized by the state, and the specific criteria are as follows:
1. No Pneumoconiosis (code name 0)
(1)0 No X-ray manifestation of pneumoconiosis.
(2) 0+X-ray manifestation is not enough for diagnosis of "I".
2. Stage I pneumoconiosis (code I), (see Figure 12-3).
(1) I has small round-like shadows of grade 1 density, distributed in at least one of each of the two lung regions, each with a diameter of not less than 2 cm; or small irregularly shaped shadows of grade 1 density, distributed in not less than two lung regions.
(2) There is a marked increase in the number of small I+ shadows, but one of the densities and distributions is insufficient to be classified as "II".
3. Stage II pneumoconiosis (code II), (see Figure 124)
(1) II has small rounded or irregular shadows of grade 2 intensity, with a distribution of more than four lung regions; or small shadows of grade 3 intensity, with a distribution of up to four lung regions.
(2) II+ with small shadows of grade 3 intensity, which are distributed over more than four lung regions; or with large shadows which are not yet sufficient for "III".
4. Stage III pneumoconiosis (code Ⅲ), (see Fig. 125) Ⅲ has the presence of large shadows with a long diameter of not less than 2 cm and a wide diameter of not less than 1 cm. Ⅲ+ the area of a single large shadow or the sum of the areas of several large shadows exceeds the area of the right upper lung area. When using the above criteria, they should be based on the following various concepts:
(1) Lung zone division method: the vertical distance from the tip of the lung to the apex of the diaphragm is equidistributed into three, and the horizontal line of the equidistributed points is used to divide each side of the lung field into three zones: the upper, middle and lower.
(2) Small shadows: these are shadows with a diameter or width of no more than 1 cm. It can be divided into two types: (1) round-like (R), with a round or nearly round shape and neat or irregular edges; (2) irregular shape (IR), referring to a group of dense shadows of different thickness, length, and morphology, which may be unconnected with each other or intertwined haphazardly in a reticular or sometimes honeycomb pattern. Both types of small shadows can be called p (diameter of about 1.5mm or less), q (diameter of about 1.5-3mm), r (diameter of 3-10mm) according to their size or thickness; irregularly shaped are called s (width of about 1.5mm or less), t (width of about 1.5-3mm), u (width of about 3-10mm).
(3) Intensity of small shadows: it refers to the number of small shadows within a certain range, which can be divided into 3 grades: Intensity of small round-like shadows: Grade 1 Definite and certain amount of small round-like shadows. The lung texture is clearly visible (e.g., p, i.e., about 10 up and down in a 2-cm diameter area). Grade 2 A large number of small roundish shadows with generally recognizable lung texture. Grade 3 A large number of small round-like shadows with partial or complete loss of lung texture. Grade 1 Considerable amount of small irregular shadows with generally recognizable lung texture. Grade 2 A significant amount of small irregular shaped shadows. Lung texture is usually partially absent. Grade 3 A large number of small irregular shadows, usually with total loss of lung texture. Density and range of determination of the density of all the small shadows in each lung area: 1. the determination of the lung area requires that the small shadows account for two-thirds of the area of the area; 2. the range of distribution, i.e., the number of lung areas in which small shadows are present; 3. the density in the majority of the lung areas is the main basis for the determination; 4. the density in the higher level with a range of distribution of not less than two lung areas is the main basis for the determination.
(4) Large shadows: shadows with a maximum diameter of 1 cm or more. Large shadows that are not enough to be classified as "Ⅲ" are: ① small shadows aggregated, not yet formed a uniform dense mass shadow; ② mass shadow is not up to 2cm × 1cm; ③ the appearance of "patchy strips" or "whitish area".
(5) Pleural changes (including thickening, adhesion, calcification), pneumoconiosis or other diseases (e.g., rheumatoid pneumoconiosis) were recorded with corresponding codes.
(6) Regarding the phases (+), in order to facilitate the dynamic observation of the disease, 0+, Ⅰ+, Ⅱ+, and Ⅲ+ were added to the phases respectively, which are not independent phases. For silicosis, when exposed to dust with high silica content and concentration, round and round-like shadows tend to predominate, first appearing in the inner middle band of the middle and lower fields of both lungs and gradually expanding upward; there are also cases in which they first appear in the two upper lungs. In the case of low silica content or inhalation of mixed dust, round-like shadows (the so-called reticular shadows) tend to predominate. In silicosis, the large shadows are localized, dense, and finally fused, commonly in the upper field bands of the two lungs, with clear outlines and a symmetrical "winged" or figure-of-eight shape in the two lungs. The fused mass contracts inward and upward, pulling the hilum out of position. The hilar shadows are often enlarged and denser, and sometimes lymph node "eggshell calcification" occurs, which is caused by subperitoneal calcium deposits in the lymph nodes. Lung texture is increased and thickened.
(2) Laboratory tests There is no special significance of general routine tests for anthrasilicosis. Serum protein hexose, amino hexose, mucin, immunoglobulin, copper blue protein and urinary hydroxyproline often have a tendency to increase, but most of them are non-specific, the normal range fluctuates greatly, its clinical value is not great.
(3) Lung function measurement Because of the strong compensatory function of the lung tissue, early patients with lung function damage is not obvious. With the increase of lung fibrous tissue, elasticity decreases, lung capacity decreases. As the disease progresses, the volume of expiratory force per second and the maximum ventilation also decrease, and the residual air volume and its ratio to the total lung volume increase. The more severe the emphysema, the more pronounced these changes are, and they cause diffusion dysfunction. The partial pressure of arterial oxygen at rest may be reduced to varying degrees. Pulmonary function measurement is of little significance in diagnosis, but can be used as a basis for the identification of the labor capacity of silicosis patients.
6Differential Diagnosis Editor
1. Diseases that need to be differentiated from nodular shadows of silicosis include the following: acute cornual tuberculosis, pulmonary ferritinosis, fine bronchioloalveolar carcinoma, nodular disease, alveolar microlithiasis and connective tissue disease.
2. The lumpy lesions of silicosis should be differentiated from tuberculosis ball and lung cancer mass, etc.: the above mentioned diseases should be differentiated from each other, which can be referred to the relevant chapters.
7Chinese medicine treatment editors
Comprehensive treatment
In terms of drug treatment for silicosis, hanfengji methylin is commonly used. This is a bisbenzylisoquinoline-like drug extracted from the Chinese medicine Han Fangji family of plants, which can reduce collagen synthesis in silicosis, and is more effective in acute silicosis, with patients taking 200 mg to 300 mg orally daily to improve clinical symptoms. Side effects of the drug include loss of appetite, elevated aminotransferases, and slowed heart rate. It has also been reported that the drug, taken together with Liufidihuangwan for six days a week for two months, can significantly improve coughing, sputum, chest pain, and dyspnea in silicosis patients, and reduce their chances of catching colds and bronchial and lung infections by 52.94%. [1]
Silicosis is mostly manifested as phlegm and stasis obstruction, so the principle of dietary therapy is to dissolve phlegm and soften hardness, and seaweed, kombu and coix seed can be used, and boiled with water. In the phlegm stasis blockage at the same time, the patient also often has qi and yin deficiency, manifested as coughing and sputum, hoarseness, etc., can choose to eat lily, pear, lotus root, luohan guo, loquat and so on to supplement the lung and yin. Silicosis advanced stage, the patient's deficiency is obvious, it is advisable to supplement the deficiency of the root in order to strengthen the body, can eat lily of the valley ginseng stewed pig lungs, astragalus stewed chicken, cinnamon and ginseng honey paste? etc.
Relief of symptoms
Formula 1 Codonopsis pilosula 60 grams, oyster 60 grams, 15 grams of plums, 30 grams of piper betel, 15 grams of amaranth, 15 grams of yuyu grain, 15 grams of Allium sativum, Poria 12 grams, 12 grams of almonds, 15 grams of Platycodonopsis pilosula, 12 grams of anterior hu, 6 grams of citrus aurantium husk, 6 grams of ginger, decocted in water. For those with dry throat and sticky phlegm, add bamboo, Zhimu, asparagus, maitake; for those with white foamy phlegm, add cinnamon stick, Chenpi, half-summer; for those with yellow phlegm and thirst, add scutellaria and gypsum; for those with fear of wind and fear of cold, add thorns and feng; for those with fever, cough and thirst, add mulberry leaves and chrysanthemums; for those with poor appetite, add hawthorn, fried malt, fried grain buds; and for those with insomnia, add farzhi and jujube nut.
Formula 2: Codonopsis pilosulae, 15 grams of gold in the chicken, 30 grams of Psidium guajava, fructus bracteatae and Psoralea mucronatae, 10 grams of Allium sativum and Rheum palmatum, 12 grams of Codonopsis pilosulae and 3 grams of placenta powder ****powdered, each time to take 2 grams, twice a day, for 3 months as a course of treatment. [1]
Qigong
Some researchers have recently reported that silicosis patients can practice qigong to alleviate their symptoms, and the gong methods that they can practice are standing pile gong, vomiting gong, qigong taiji fifteen potentials, and self meridian point guidance.
Cough, sputum, chest pain, asthma are the four major symptoms of silicosis, silicosis patients practicing qigong three months after these symptoms can be improved; at the same time, the patient's general condition can be improved, such as increased appetite, bloating disappeared, insomnia is reduced, the number of colds is reduced, or colds caused by a reduction in the degree of lung infection. Some studies believe that after practicing qigong, the lung capacity and body regeneration function of silicosis patients will be improved. The therapeutic effect of practicing qigong on silicosis patients is not the elimination of silicosis nodules and fibrotic changes in the lungs, but rather the adjustment of the functional status of their whole body systems, so that the symptoms of the respiratory system can be improved on the basis of the improvement of the whole body situation. This reflects the characteristics of qigong practiced by the mind and body together and the holistic concept of Chinese medicine.
When practicing qigong, patients should choose appropriate gong methods according to their own actual conditions, make comprehensive use of the three types of practice means, namely, body conditioning, breath conditioning, and mind conditioning, and insist on long-term exercise to gradually improve respiratory function and enhance physical fitness. [1]
8Treatment instructions edited
For patients who have been diagnosed with silicosis, comprehensive measures should be taken, including transferring away from silica dust operations, strengthening nutrition, adhering to medical sports and increasing the body's ability to resist infection. At the same time for the patient's condition, symptomatic treatment. The four clinically applied drugs, namely, Hantahexin, Piperaquine Hydroxyphosphate, Cirsiline and Aluminum Citrate, are effective in different aspects of silicosis occurrence and development, but the exact mechanism of treating silicosis is not yet fully understood.
(I) Kespin (poly-2-vinylpyridine nitrogen oxide) is a polymer compound with a molecular weight of about 100,000 or so. It has a protective phagocytosis function, and can form hydrogen bonds with silica dust and adsorption, so that silica dust to reduce the role of fibrosis. Clinical application: 4% aqueous solution 8ml (320mg) nebulized inhalation, 6 times a week. Take 3 months as a course of treatment, each course of treatment 1 month interval. It can be treated for 2 to 3 years. The treatment can improve respiratory symptoms and reduce respiratory infections, and delay or stabilize the development of lesions.
(2) Aluminum citrate Aluminum citrate can closely cover the surface of quartz dust particles, protect macrophages, attenuate the fibrogenic effect of quartz. Usage: injection 10mg (Al) once a week intramuscular injection, or an aqueous solution of 50mg (Al) per week, divided into nebulized inhalation, for 6 months, stop for 2 months, for a course of treatment.
(C) piperaquine hydroxyphosphate (antisilicone 1) experiments show that it has the effect of inhibiting collagen synthesis, protection and activation of macrophages, and improve the immune status of the body. Tablets orally, 2 times a week, 0.5g each time, the first dose is doubled. Continuous service for 6 months, stop 1-3 months, for a course of treatment. After the application of 50% of the patients symptoms improve, X chest radiograph lesions most of the stabilization, a few cases of shadow fade or become smaller.
(D) HANDFENGJI METHODOLOGY (HANJIAO METHODOLOGY) This product can be combined with collagen macromolecular proteins and decompose them; improve the vitality of macrophages; promote phagocytosis of degraded collagen macromolecules and proteoglycans, and affect the polymerization of collagen fibers; it also has the role of protecting alveolar surface-active substances. Clinical application of 300mg daily oral, 6 days a week, for 3 months, stop for 1 month, for a course of treatment, after treatment for 2 to 3 years, respiratory symptoms are reduced, X chest radiographs of lesions stabilized, and a small number of lesions become lighter and smaller. Side effects are skin pigmentation and itching, about 1/5 patients with abdominal distension, about 9.8% of liver function abnormalities. In order to improve the efficacy of the drug and reduce the toxic effects, the combined use of drugs is proposed. For example: han methanol 100mg, 2 times a day, 6 days a week, plus antisilicone 1 0.5g, once a week, 3 months for a course of treatment ****6 courses; han methanol plus 1% kespira 144ml in fiberoptic bronchoscopy under the introduction of drip, once a year, ****2 times; aluminum citrate weekly intramuscular injection of 20mg, plus antisilicone 1 0.25g, twice a week, orally, ****6 courses. The results of the treatment showed that respiratory symptoms and infections were significantly improved. x-ray showed that the rate of improvement and the rate of stabilization of the condition were higher than the control group; and the lesion progression of the fast case effect is obvious, and the nature of the work type is also related. The combination of drugs reduced the dosage of drugs, thus reducing the side effects.
9 Complications Edit
(a) Tuberculosis It is a common comorbidity of silicosis, ranging from about 20% to 50%. It is more commonly found on autopsy than on lifetime radiographs, about 36% to 75%. The rate of comorbidity increases as the silicosis condition worsens. Combined tuberculosis often contributes to the death of silicosis patients. According to domestic and international reports, silicosis patients died of combined tuberculosis accounted for 46.3% to 50.8%. Silicosis patients are easy to combine with tuberculosis, may be related to the following factors:
①Silicosis patients with lowered resistance, susceptible to tuberculosis infection;
②Widespread interstitial fibrosis of the lungs, resulting in impaired blood-lymphatic circulation, lowering the lung tissue of the tuberculosis defense function;
③Silicosis dust has a certain degree of toxicity to the macrophages, weakening the phagocytosis of the macrophage and sterilizing ability to promote the growth and seeding of tuberculosis in the tissues. The growth and dissemination of tuberculosis bacteria in the tissue. Laboratory tests include accelerated erythrocyte sedimentation rate, and tubercle bacilli can be found in sputum. Tuberculous cavities are often large and irregular in shape, mostly eccentric, with papillary projections on the inner wall, shaped like caverns. The pleura around the tuberculous lesion is thickened. Because of the extensive fibrosis of both lungs, affecting the blood supply, the efficacy of anti-tuberculosis drugs is very poor.
(2) chronic obstructive pulmonary disease and pulmonary heart disease Due to the body's reduced resistance and diffuse fibrosis of the two lungs, the bronchial tubes are narrowed, poor drainage, easy to secondary bacterial and viral infections, and complications of chronic bronchitis and emphysema, lung function is reduced, resulting in severe hypoxia and carbon dioxide retention, and respiratory failure occurs. Severe silicosis can be accompanied by pulmonary hypertension, leading to pulmonary heart disease. Severe infections can cause right heart failure.
(3) Spontaneous pneumothorax After holding one's breath with force or coughing, the alveoli rupture, resulting in tension spontaneous pneumothorax. Due to pleural adhesions, the pneumothorax is mostly limited and is often concealed by the original dyspnea symptoms, and is sometimes detected only after X-ray examination. Pneumothorax may occur repeatedly or alternately on both sides. Due to fibrosis of lung tissue and pleura, the breach is often difficult to heal and gas absorption is slow.
10 Preventive Notes Editor
To control silicosis, the key is prevention. China's factories and mines around the use of wet work, closed dust source, ventilation and dust removal, equipment maintenance and overhaul and other comprehensive dust control measures, coupled with personal protection, regular monitoring of airborne dust concentration and strengthen publicity and education, so that the incidence of silicosis is greatly reduced, the onset of prolonged working age, the progress of the disease is delayed. All factories and mines should do a good job of pre-employment physical examination, including X-ray chest radiographs, for new workers participating in dust operations. Anyone with active tuberculosis inside and outside the lungs, various respiratory disorders (chronic rhinitis, asthma, bronchodilatation, chronic bronchitis, emphysema, etc.) should not participate in silica dust work. Workers in factories (mines) should make regular physical examination, including X-ray chest radiographs, and the examination interval is determined according to the exposure to silica content and the concentration of dust in the air, once a year to two or three years. If suspected silicosis is found, close observation and regular review should be emphasized; if silicosis is diagnosed, the workers should be transferred out of the silica dust operation immediately, and appropriate work should be arranged according to the appraisal of the labor capacity, and comprehensive treatment should be given. Silicon dust factories and mines should do a good job of preventing tuberculosis, in order to reduce the incidence of silicosis combined with tuberculosis.