How does farmer lung return a responsibility?
summary
Farmer's lung is a kind of exogenous allergic alveolitis caused by inhaling organic dust containing thermophilic actinomycetes. Most patients are engaged in agricultural production, so they are called "farmers' lung". In addition, there are sugarcane pneumoconiosis, mushroom pneumoconiosis, potato pneumoconiosis, humidifier pneumoconiosis (or "air conditioner pneumoconiosis") and so on, which can be caused by their living environment containing a large number of thermophilic actinomycetes. Some people classify anaphylactic pneumonia as this kind of disease, but the meaning of anaphylactic pneumonia is more extensive and should be differentiated. The foreign reports about farmer's lung began in 1932, but the etiology was unknown at that time. It was only after Pepys and others found antibodies against thermophilic actinomycete antigen in the serum of farmer's lung patients in 1962 that they confirmed that the disease was related to type III allergy. Since 1981, there has been a case report of farmer's lung confirmed by autopsy in China.
How does farmer lung return a responsibility?
Thermophilic actinomycetes are widely distributed in nature. Grains or rice straw (including bagasse, mushroom residue, potato residue and dust in indoor humidifier or air conditioner) are moist and moldy. The temperature and humidity in the haystack can reach 40 ℃～ 60 ℃ and 45% respectively. These are the favorable conditions for the growth of thermophilic actinomycetes.
Inhaling a certain amount of thermophilic actinomycetes is the pathogenic condition of farmers' lung, but when working in the same environment, only a few people get sick, which indicates that the disease is related to the susceptible factors of patients. Although a small amount of pathogens may be inhaled by non-agricultural workers in rural areas, they can only be found in the serum antibody to precipitating factor, but not in the disease.
When the patient inhales the antigen to the alveoli, it can stimulate the body to produce the corresponding antibody (IgG or IgM). When the patient inhales the same antigen again, the antigen and antibody in the lung tissue combine to form an immune complex. Under certain conditions, they can deposit in the basement membrane of blood vessel wall, activate complement C3, release anaphylactic toxin, form complement components with chemotaxis, and lead to the release of lysosomal enzymes in the process of phagocytosis of antigen antibody complex, causing inflammation and tissue damage. Antigen can also contact with sensitized lymphocytes in the body to produce a series of lymphokines, directly or indirectly causing tissue damage. In addition, thermophilic actinomycetes can directly activate the complement pathway, damage lung tissue, or produce some proteolytic enzymes, leading to lung inflammation. Since it is an inflammatory reaction, it may be similar to other inflammation, and some cytokines or mediators may be abnormal. For example, it has been reported that interleukin-2 (IL-2), interleukin-2 (IL-2), interleukin-2 (IL-2), interleukin-2 (IL-2), interleukin-2 (IL-2), interleukin-2 (IL-2) and interleukin-2 (IL-2) γ- Interferon and adhesion molecule-1 may be the factors of lung disease and lymphocytic alveolitis in farmers. At present, there are few researches on this aspect, which need to be further studied.
matters needing attention
To avoid contact with thermophilic actinomycetes is the fundamental measure. The patients with recurrent lung disease should change their occupation and leave the disease environment. If the disease does not recur after only one or two times, they can still engage in the original work after taking some preventive measures; ② Grass and grain should be stored in a well ventilated place with moisture-proof equipment after fully drying; ③ Mechanization and automation can reduce the chance of spore inhalation; ④ Spraying 1% ～ 2% propionic acid in the forage can prevent the forage from mildew, but it is expensive and should not be used as feed; ⑤ Positive pressure airflow protective helmet, etc. can be used if conditions permit; ⑥ Patients with symptoms should be treated in time, followed up and observed, and those with irreversible lesions should be transferred from work to prevent serious complications.
